I'm sure you already know this, but an A/C system that "short-cycles" like this is the direct indicator that it is oversized for the conditions (home load compared to outside conditions). If that every-15-minutes cycling is happening around your peak summer conditions, you'd really benefit from some measures to address this. Eventually down the road when ready to replace your A/C, you can go cheaper and just get a one-size-lower capacity to better match, or invest in better answer, a higher efficiency unit that includes a VARIABLE or STAGED compressor at full size. You'll have the capacity to retain the ability to address higher temperatures during hot spells, but gain the incredibly more efficient handling of your A/C during the rest of the year as it runs at lower capacity. You'll get longer run-times at lower energy use, and it will properly dehumidify the air. For now, there are also programmable thermostats that allow you to set a wider dead-band and other features, so that you can have it wait an extra degree above setpoint before activating the compressor, and run it an extra degree or two below the setpoint so that cycle times are extended and more dehumidification can be effected. Also, be sure your thermostat location is away from sun exposure on an interior wall, and is NOT directly in the path of one of your supply air diffusers. Side note: You've probably already gotten the advice that you cannot get an accurate spot reading of temp with your IR pistol on reflective or bare metal surfaces (paint a section matte black first?). You may wish to add that installing the reflective radiant barrier like this does block a large chunk of the radiant solar load from being absorbed into the attic, but retains the full airflow from the soffit-vents up to the ridge-vent so that roof sheathing and structure is still fully vented and airflow will actually be better, minimizing any potential increase of temp to the shingles. This concern about shingle temps goes away completely once you upgrade your roof to a metal one. Keep up the information sharing!
@@markchristensen5206 I’ve used this technology for years. There are numerous products for different applications. A different application is to install the perforated product directly on top of existing insulation and cover duct at the same time if applicable. If not, wrap ductwork with the double bubble double foil (the Mercedes of all products!) This product can be layered in rafter spaces, installed 3/4” apart giving tremendous protection. I get mine direct from the manufacturer in Texas for about $.12 sf. Innovative Insulation. There is a demonstration on TH-cam which is the same one I saw many, many years ago. These products truly work! Radiant Barrier Is It a Scam Sarasota Energy Saver video
Make sure to also measure the temperature split between the return and supply it should be about 20 degrees. If it's not try adjusting your blower speed, sometimes they set them up with too high of speed. Fixing this will also help it dehumidify the air.
You can't get an accurate temp reading when using an IR gun on metallic surfaces due to high emissivity. The reading displayed will be significantly lower than what it actually is. Try putting a small square if black electrical tape on the metal and then point the gun at that for a more accurate measure of the radiant energy. I'm looking to do this barrier install to my house here in Australia soon. Thanks for the info.
The 10 degree temperature difference I measured for my post compared of the surface of the cellulose (shredded light gray paper treated to make it resist burning) to the ambient temperature (down low) of my attic.
Good info. It works! Just installed 2-sided foil- backed bubblewrap (pressure fit, no air gap) inside a couple of kitchen cabinets against the back wall. Did this because our coffee cups would need to be heated with hot tap water to prevent cooling our morning cup of coffee. After a cold 25 degree F night, a cup located inside the newly insulated cabinet was just as warm (same temp by feel) as a cup that sat on the counter overnight in a 68 degree F kitchen.
I have a comment about the tip you gave about leaving an air gap so the heat doesn't conduct straight through the radiant barrier. Even if you have the radiant barrier pressed right up against the wood and the barrier itself gets hot, you still benefit because of an interesting bit of physics: shiny things, which are really good at reflecting radiant heat are intrinsically poor at radiating heat themselves. If you look for physics demonstrations of emissivity, you'll see demos where two metal cans filled with the same temperature water with the only difference being that one can is painted matte black and the other is polished shiny do not look like they're the same temperature when viewed with an infrared camera. The shiny one looks many degrees cooler even though the heat conducts right into the shiny part, simply because reflective surfaces are intrinsically poor at radiating heat. You can actually get even better performance if you use multiple layers with gaps between them. Have one radiant barrier pressed up against the wood, and then have another with a gap between the two. Radiant barriers are not 100% efficient; a few percent of the radiant heat still makes it through. Suppose the leakage is about 4%. If you have two layers, then the first one lets through 4%, and the second lets through only 4% of 4%, which is 0.16%. This repeated attenuation of radiant heat is how the multiple radiant barriers of the James Webb Space Telescope are able to keep the shaded side at temperatures a few degrees absolute zero (Kelvin scale) while the sun-side gets to temperatures of about 230˚F (383K).
Layering is the ultimate system. There is one type called double bubble double foil that even carries an R-value. Since a radiant barrier is a totally different animal than fiberglass or cellulose, it doesn’t have a measurable R-value as such. Fiberglass is only puffed up air and just slows down the airflow. That’s why it takes so much of the nasty stuff!
i considered the idea of installing multiple layers. but, of course, it is best to do this on a new build. it is exponentially harder to do this on an existing and occupied structure, especially with such awkward and confined spaces. rather, i'm planning to just install one layer on the joist and one on the attic floor. the rolls i purchased are perforated to allow moisture to escape. had i considered radiant barriers earlier, i would've included it behind the vinyl siding that i helped my dad install
I have an 2000 sq ft attic. The sheathing is OSB with a reflective lining on the underside. I then have reflective foil staples to the bottoms of the roof rafters. My attic space is horribly hot. Shouldn't both layers of radiant barrier ellimate most of the heat? Why then is my attic still hot? I have a light colored metal roof screwed directly onto the sheathing. I shrug my shoulders and scratch my head wondering if the reflectivity of these products are worth the expense. My attic should be around 90*, but i know it's a lot closer to 120*.
@@tynyyn5344 Is your attic ventilated? Roof/ridge vents? Sometimes people seal off the ventilation when installing radiant barriers, and that defeats much of the purpose. The heat in the attic still needs a place to escape regardless of type insulation.
Howdy Barry. Thanks for taking the time to reply. I have half of the attic ceiling ventilation blocked off because of calculations used to figure out how many square inches of soffit vents I need. According to the research I did, I only need a certain amount of ridge vent in order to make the soffit vents work properly. Thus I sealed off half of the ridge vents. Should I unseal them? @@barrygrant2907
It's not only the heat from the roof, and attic. it's ,also, 3 more things that heat up your home.. 1, holes in the ceilings, from,, The can lights, the ceiling fans, and the heating and cooling, registers. The heat from the attic in summer, comes through the holes. The cold in winter comes through the same holes. I sealed the space between the sheet rock, and fixtures. No air movement. 3, a gable fan that is thermostat controlled. It blows the hot, attic air out. 2, My home came with blown in insulation, no good home got hot. You could feel the waves of heat coming down from the ceiling. I added R13 in the attic. It slowed down the waves of heat, not enough. I then added R 25, for total of R 38, what a difference. No more waves of heat. Yesterday it was 112° outside, our home inside got up to 72°. We have no air conditioning. What we also have is a whole fan. We turn it on at night, when the outside temperature is less than the house temperature. Most mornings the house temperature starts at 64°. We not only cool the house down we coolthe attic temperature as well. The whole house fan cost about .06 cents per hour to operate. At the time of writing this, it's 1 pm, and , 100° outside, and a cool 68° inside, we started the morning, at 64° inside the house.
I put up an attic fan for $40. I got a Vornado clip on fan on clearance for $10 and a digital temp controlled outlet for $30. When the attic gets hot, the fan turns on and blows the hot air out of an attic vent. I'm also about to put up radiant barrier
@@wokejoke2675 I installed radiant barrier, was not happy with the results. I installed R25 fiberglass insulation on top of the barrier, that made the most difference in the temperature inside the house, I'm adding an additional R 38 on top of my current R 38. The gable fan should not be based on price, I use to be price conscious. Now I'm volume of air conscious, the more times you can exhaust the attic air the better, my attic is 7,000 cf. A 1,050 cfm fan takes 7 minutes to exhaust the attic, 8 times per hour. I'm replacing my current gable fan, 1050cfm, with 2,800 cfm. That's roughly 3 minutes to exhaust the attic air, or 20 times each hour. The more volume the faster your attic cools
As a side note, it is much hard to heat/cool very humid air. You can heat/cool less humid air very easily. As an example, look at deserts, their temps go up and down drastically with their low humidity.
I could not believe the difference it made with the method I tried. I found white highly refractive roof paint at the hardware store and painted my flat roof with that. It made a MASSIVE difference. Easily 5-10 Degree Celsius cooler than ambient in the house now. I left a small section uncoated on the roof close to where the ladder was for comparison and the white roof feels as cold as the steel of a pot you took out of your kitchen cupboard and the old paint(Dark grey) is scolding hot.
@@LightGesture black only will help if the roof dont have insulation. if have some insulation the heat triiying to come in say wtf is this you want me in or what?
I've got attic foil on top of my blown-in cellulose insulation and it definitely helps. On a hot day the temperature under the foil is about 10 degrees less. Keep in mind that when it's placed on top the insulation on the floor of your attic the air gap is above it with only a small air gap provided beneath. When it is bouncing up is the radiant heat in hot the attic air. I have taken another step. To keep the heat radiating from my roof away from the floor of the attic I've also placed a wrap of 4-foot-wide attic foil around the base of my attic. That starts the heat radiating from the lower shingles moving up. On a hot day the air exiting up at the top of that foil is about twenty degrees hotter than the foil itself. That also creates a chimney effect as moving air moves other air up and out of the way. The one weakness is my house is that it lacks sufficient ridge venting, but at least I can push that heat upward where it eventually exits. One final remark. The foil I'm using comes from Attic Foil, which has a website with that name. It is very heavy duty. You can walk on it repeatedly without tearing. Also, for humid climates you can get a foil from them with holes in it to keep moisture out of your insulation.
Have you noticed any financial benefits? Have you been able to notice a significant change in temperature or how often your HVAC system is working. I have a small home with standard trusses and my easy way would be to lay it on the insulation as well. I hav all fiberglass insulation and really don’t want to crawl into that space anymore than needed.
We love it! Also, we used some extra we had to survive the crazy freeze with no power for 3 days. We covered all the windows and doors from the inside. Prior to putting it up our house interior was below freezing with the fireplace on. Once we put it up, we could keep the house at 55 degrees with the fireplace. Also, none of our exposed copper pipes in the attic froze. At least half the houses in our neighborhood flooded from burst pipes in the attic.
@@GrayHouseStudio I live in South West Missouri and fernice/ductwork is under the house. A/c is outside and I have big gabel vents. My house has minimul shade would you still tecommend this product of a DIY? Donyou still think its worth installing after having it for so many years? Thanks just price of electricity is getting up there these days in mid 2022
@@ddemier I can set you up with my supplier in Texas. The basic product is about $.12 /sf up to about $.29/sf for the best product they have. You can order it direct from the manufacturer. I’ve used it for many years and in these tough times, I’m trying to help as many people as I can. I’m only passing on great information on a product that truly works. I have used it as a house wrap and in the attic for many years in my construction business. Everyone needs to use this before the shipping lines are totally shut down. Let me know if I can help, and spread the word!
The air gap between sheathing radiant Barrier the insulation. Installed by radiant barrier on my remodel and the space above radiant barrier was 125 degrees and 80 degrees below it. With only a single layer of vapor permeable vapor barrier. With adding 800 Sq ft. Contractor said I’d need a new HVAC. It’s running better than before remodel.
I live in Phoenix, have lived in other climates. My biggest improvements has been insulation and using mini split AC. I furred inside walls so 8" and max attic insulation. The mini split AC allowed for controlling every room separately, no ducts in attic and returns grills.
I had a similar with the air conditioner cycling, and found that it was due to one of the vents pointing at the thermostat. Turning that register fixed the short cycling issue. Later in the year when the 40k btu air conditioner was on 14 hours a day continuously, I installed a gable vent fan, and the interior temperature dropped 8 degrees even though it was 6 degrees hotter outside when I took the second measurement. Btw peak daily humidity is about 85%.
Been a bit since this was posted, seen your channel is not making many videos anymore. I would highly suggest using a FLIR (even if you buy it, check the areas, and return it soon after) to see if there are air leaks around your fixtures in the walls and ceiling, and even pull apart some of the insulation around the ducting to ensure that there are no leaks in the ducting itself. Checking you have enough soffit vents to ensure no air is being pulled into your house from outside by the heat rising to the top and pulling some air from your house into the attic. I also believe from what I have seen here on TH-cam it is better to have it directly over the insulation. They are made to be vapor permeable, however, if you have it over the insulation itself you ensure no air movement over the insulation that could reduce the R value by blowing through the top few inches. Hope all went well with this as I don't see really an update on it after 3 years.
I have lived in a new housing estate (in Australia) for seven years. Every house that I have seen built has the roof sarking and wall wrap fitted with the coloured side out and the shiny side in. I addition the manufacturers advice says to do it this way. I am not prepared to argue the case but am simply stating that this is how it is normally done.
video didn't seem to answer the questions. I would like to see: - if for a given time period if the AC cycled less frequently after barrier installation compared to before. - for a given time period, show graph of the attic temperature fluctuations, before and after. Duct temps as well, although I am less interested in that. I just want to know if this has the potential to decrease my AC frequent cycling problem and have data to support it. It seems like you only pointed the IR thermometer and showed the barrier was cooler. That should translate into cooler attic temps and less AC cycling, but you did not show that. You showed a graph of the before condition only.
What an informative video! I use that same stuff in car restorations - awesome barrier inside the car, on the front bulkhead (to reduce engine heat transmission). I also use that stuff for custom car shades.
You likely have your thermostat too close to a vent. It is seeing cold air immediately then shutting off. Try putting it somewhere with little to no airflow from the ac.
Haha, ya we are great! We started a business moonrockprints.com and it has been keeping us busy. We haven't forgot about the channel and hope to have the space to make more videos soon. It feels good to have you ask!
Yep, I like this sort of video where real world temp monitoring is done. Your subscribers are curious to see the after effects of this radiant barrier as well as AC cycle and temp information. South Louisiana is BRUTAL this year with the temperatures!!!
I used Atticfoil, $150 a 4'x125'. Stapled(electric) to underside of the rafters. Atic floor measured 130degrees on a 100 degree day. After installing attic floor measured 95, exact same time and conditions. Roll of foil paid for it self in 1 month. I'm saying this because you never really showed the real cost saving impact or even answered your own question. Yes, radiant barrier works.
I also used a Sense monitor in my house and the first thing I did was install a gable fan and that wasnt enough to cool my attic so the next thing I did was install a radiant barrier in my attic and my attic temperature went from 156F on a 98F day to 112F on a 98F day. My energy usage from my air conditioner dropped 75%. I also turned off the attic fan to see how much it helped and the attic fan plus the radiant is the combination you need
Vent fans will cool your attic but they mostly do so by sucking cool air from your living space. It turns out that negative pressure in the attic is a bad thing.
@@Lew114 if you’re pulling air from your living space then that means you don’t have adequate soffit ventilation and also means you should be sealing things like top plates and ceiling penetrations.
If there's a part of your house that isn't being cooled or heated properly-perhaps a child's bedroom or bathroom far away from your central HVAC, there's a useful technique to correct the problem. Overdo the insulation and foil for that room to better equalize the temperatures. Thick curtains in windows also help.
a quick test of this principle is to turn on the stove (high). Use a piece of aluminum foil, hold it between your face and the stovetop (within a foot) and it will block that radiant heat. Use a similar sized panel of thin paper from the same distance and you will feel the heat radiance. It works to stop heat transfer via radiant transfer. Aluminum is a strong conducter of heat though.. Once it touches the burner, it quickly heats up and will "radiate" that heat (as well as strongly conduct it... excellent heat sink).. so the gap is needed,
You should do your due diligence before posting something as ludicrous as this. Radiant barrier is as different as night and day from “tin foil”! Reading from a box of Reynolds Wrap: to avoid possible heat damage, do not cover oven floor or an entire back… Radiant barrier is 99.9% aluminum and reflects heat.
reflective mylar is a better example. i had small air conditioner unit in my room that ran an exhaust duct to the window. the duct was just a thin tube of accordion plastic that leaked much of the heat back into the room. i took an emergency blanket (mylar) and wrapped it around the duct, then zip tied it.... massive difference to the touch
Here on pacific NW it doesn’t get very hot for long in summer or cold in winter. Very common to have no central a/c but there’s just a few weeks of 95-100 d , so I’m adding this product.
make sure your soffits are perforated and you have a good ridge vent, and you still need to let your attic vent, so you could stick to gable vents for that
6:11 the infrared thermometer test is misleading because the back side of the radiant barrier is not going to have the same emissivity as the wood. For this reason, IR thermometers are not accurate at measuring the temperature of things that have different emissivity. For an accurate test, you need a matte black sticker on the wood, and the same matte black sticker somewhere on the radiant barrier, and you need to do the IR reading on the sticker only. By comparing the IR reading off of the same kind of surface (one with good emissivity, where the IR reading most accurately tells its temperature) your IR thermometer reading will be accurate. If you don't do this, the readings are misleading. For a good demo of this, you can get two paint cans, paint the surface of one matte black, and polish the other or tape foil tape on it so it is super shiny, then fill both with boiling water. After a minute or so, both cans should be at the temperature of the boiling water inside. Read both using the IR thermometer. You will get wildly different readings though a hand-test (feeling the can with your hand) will show you that the temperatures are the same. This is the clearest demonstration that IR readings only make meaningful comparisons if you read off of the same kind of surface, and if that surface is emissive enough where the IR reading gives a realistic indicator of the thing's temperature.
Yeah man I do AC work and if your system isn’t removed the humidity it’s either oversized or your thermostat located in the Supply airstream and it’s causing it to short cycle.
Usually it’s just not charged to the correct Subcool/superheat level. Anything under a 17* split is usually not removing too much humidity. However most homeowners never notice the difference. I’m in the Deep South and have never seen mold growing in a attic. Maybe a little in the wet winters but dries up dead as soon as the summer heat bakes it up
If you lower the inside blower fan speed, your A/C will pull more humidity out. From high to medium or next lower speed, I wouldn’t put on low speed as it may cause coil to ice.
Crest Exteriors in North Texas sold us a “radiant barrier” in 2017 when they replaced our roof after a hail storm. NO AIR GAP, making it a waste of money on an expensive underlay. Per LOGAN at CREST, air gaps are not needed, when responding to my telling him the manufacturer disagrees with him. Logan knows best as he has installed 100’s of these per himself. Doing something incorrect to hundreds of clients doesn’t make it right. Crest has refused to do anything about this. Now, a few weeks ago, APPLE ROOFING came to do an inspection, confirmed the radiant barrier is not installed correctly. This is also when I tell them it was installed by Crest. This is when they told me that APPLE and CREST are the same company. I have yet to receive written report from their inspection and no response to emails and texts. I believe in Texas there is a 10 year statute of limitations on construction defects due to difficulty in detecting them. Suggestions are appreciated. They also tore down the gazebo my recently deceased (at that time) dad built without consulting us, and then charged us $1200+ for new one (this was hail damage and an insurance claim). They also accused us of not paying our deductible, which I handed directly to Logan when he came to pick it up at the house.
Radiant barrier which is silver on both sides is more efficient, since it lowers emissivity on the lower surface, and so reduces infrared transfer to the attic floor.
I have my thermostat throw set to 1.5 degrees vs 1, that causes it to cycle less, which I think is more important for energy savings in the Winter, but still, less disturbing at night in Summer because going on/off less. Very interesting video, I have reflector on the roof decking but still 135 in attic. Does sound like AC oversized if not running enough to dehumidify.
The duct barrier only helps when the AC is running. At other times, the dead air inside the ducts is heated up by the high attic temp. The trick is to reduce the attic temp.
@Gray House Studio question on this... I noticed the temp of the sheet of plywood was 140, vs 130 degrees on the 2x4. In hindsight, do you wish you applied a strip of foam tape to the 2x4 before stapling the foil to reduce thermal bridging and keep more barrier from conducting from the wood to foil? Or do you think the difference would be negligible? Thanks :)
your ac unit is oversized. depending on what you have you may be able to do some tuning to get better dehumidifying and all around better performance. 15 mins on and off sounds like a cycle setting in your thermostat also. your on the right track though.
Why would you leave a air gap at the bottom and the top I installed mine all the Way to the outside of the exterior wall plate and then up to and around the collar bracing. I then installed a dual power solar ventilator on the roof above the collar bracing. I also installed 1 x 4 boards horizontally every two feet to allow air to transfer from one rafters to another. End result is air is drawn from soffit vents in and up the rafters then outside by the ventilator. My attic temperature is only a few degrees different from the home temperature. Any opening in the barrier is just allowing heat back in the attic. I can’t figure out why nobody else is noticing this on the internet
From all I've heard if you seal it up it can create moisture especially in humid climates. Hot air would typically rise so the air can be pulled from the gap at the bottom of the installation up and be released through the gap at the top. All the manufacturing instructions appear to recommend the same thing - gap at top and bottom. Not that that's the only way to solve the issue of course as your solution may also work well.
An air conditioner doesn't just remove heat it also dehumidifies and if the air rushes over the coils to fast it won't have time to take out the humidity.
I've thought about installing a relay with a dryer style temperature switch so that my fan wouldn't stay too low. I think I could leave the hot side alone if I think about it.
We have a metal building that we are adding stick framing to, for a canin. Would we be able to add this reflective barrier along with batt insulation to achieve proper R-value with less space?
So whats the long term result? Are you noticing your AC not kicking on as much? Has gas this radiant barrier impacted your electric bill? Would you still recommend installing this radiant barrier to a D.I.Y.?😊
Great video. I have same problem , ac takes like 5 hours to cool from 80 to 73, the ac is managing my bill, it is killing me. I live in Katy Tx and my roof has that feel in the sheeting. Do you thing the radian barrier will work even if i already have the film on the sheeting? thanks
Hi there, I am planning to put aluminum bubble insulation under the ceiling (leaving an air gap of 1.5 or 2 inches), so it would be wood /air gap /or aluminum bubbles. My intention is to reduce the radiant heat that comes from and through the wood (from the ceiling). Will this work? (I live in San Diego, not a humid place, but temperatures in summer fluctuate around 95 °F.) My second question is: what is going to happen within the airgap? Is it likely to generate humidity and potentially mold?
Watch the video: Radiant Barrier Is It a Scam? Sarasota Energy Saver This is the same demonstration I saw many, many years ago and I’ve used it ever since in my business. Any questions let me know. There are many types of radiant barrier products.
I did this in our attic years ago when I was young enough to get around in there!! Also there was enough room to move around in there. I opted for going with blown in insulation in our next house. Zero help in my opinion. If I am feeling frisky I may try the radiant barrier and here. Thanks. It would be great to see your numbers for next September and compare.
If you use white Roofguard 700 on you asphalt roof every other year, it eliminates the need for a radiant barrier and you will have a forever roof. After I applied several layers, my attic went from 145+ midday in the summer to 5 degrees above ambient temperature.
You applied this to your residential home? Just wanting more detail. Say I bought this product and painted my roof on a one story home with an attic and around a 30 degree angle.
@@toolandmaynard My roof was leaking and the shingles were curling up. I used a 3/4" nap roller with a 12ft. pole to backroll Roofguard under the shingles and pressed them back down. I used 3 layers the first time to seal everything. I've been reapplying about every 1/3rd year since. Now it's a solid coat. Any groves I filled in. The downside is snow doesn't melt like a normal roof. My neighbors will have ice dams and ice sickles and then go dry while my roof will just sit there full of snow. So if you get a lot of snow, that might be an issue.
Interesting. I have a couple areas that are weak in my roof and leak slightly. Sealed it with tar haven’t noticed an issue yet. I’ll look into this. The snow not melting is a sign of good insulation. I get what you are saying though. Thanks
I have some insulation material.. one side is shiny & the other kinda has a yellow cotton candy like 3 inch soft material. Would this be good for a dog’s house? My neighbors dogs are outdoor only pets & they both suffer in the cold. The owner only provides them with food. Any advice?
Hello, thank for the video, would you please post a link to the product you used. I don't have soffit vents but do have gable vents, would this still work for me?
ATTACH IN THE ATTIC BY STAPLE TO THE RAFTERS, THAT MAKES THE AIR GAP. OR LAY KN TOP OF EXISTING INSULATION. IF USING THE PROPER RADIANT BARRIER IT WILL WORK. IT WAS USED IN SPACE TO CONTROL TEMPERATURES IN SPACE SUITS AND MODULE
Foil stapled to rafters has another advantage. It channels the heat up creating a chimney effect. That keeps the hotter air away from the insulation above your living areas.
building a home so that the roof is separate from the home, will prevent this issue. Think of the roof as a tree shading the house fully, and the house underneath, it has a 2nd roof to seal off home from outdoors. This way, attic is free to vent all that heat, home is shaded all day.
That was super helpful. I'm thinking of tearing off shingles...laying out some foil product...putting on 2/4 sleepers over the trusses and a new layer of plywood. Forming a cold roof. tHanks for your insight.
Unless you just need a new roof, I would install radiant barrier either on top of existing insulation in the attic or between the rafter spaces. Let me know if you need any advice.
@@rayburnyarborough4695 tHank you. Yes, this roof is a tear off. So new shingles are the plan. I want the cold roof for the house, that is why I came across the idea of laying out the foil over the old decking....then adding 2X material and new plywood over that. Any ideas and advice is more than helpful. I need all the opinions I can find.
@@rayburnyarborough4695 tHank you very much. The plywood on the existing roof is just 3/8" (1960s ideas). Rather than tear it off, I will simply make a cold roof and apply another layer. Same money except for the 2X material that will be used as a spacer between layers. This is how I have an easy opportunity to put the foil on. Still need opinions, please share any thoughts.
@@Dancing_Alone_wRentals Great! Call Innovative Insulation and talk to Matt Russell. This is the manufacturer in Texas. Their website is a wealth of information and different products. Tell him I told you to call. He can advise you on the best application and you can order directly from him, saving tons of money. I just spoke with him. You might only need one more layer of 3/8 plywood, however it might cost more than 1/2”. The savings on the radiant barrier might allow you to purchase a 1/2” Advantech sheathing. That stuff lasts forever. I always shop around. Try to go with a local lumber supply rather than the big box stores if possible. Good luck 😎
The insulation will always run ambient more than what the actual room temperature IS... My block exterior walls that are bare are currently -5F. The insulation reads 40F. Inside temperature it is 34F. I have foam board laying around and it's 58F. I can see my breathe and it's freezing .. Question is, how much did it cost... and how much are you saving?
Yeah I'm interested in this. I'm just wondering how would you use something like this in a semi truck? It gets so hot inside there's so quick and trying to cool it off. It's hard. Cause there's no way to create a airspace.
I’ve been spreading the word like wildfire. I’ve used radiant barrier for a long time in my business. I can set you up directly with the manufacturer in Texas and you can order it directly. There are different products for different applications ranging from about $.12/sf to $.29/sf. I’m just trying to help my fellow brothers out. Watch the video: Radiant Barrier Is It a Scam? by Sarasota Energy Saver for a great demonstration. This is the same one I saw years ago and I think they wanted about $1.50/sf to install. A get rich quick operation. I did my due diligence, as I always do, and found the manufacturer in Texas. The only thing I would get out of this is the satisfaction that I’ve helped someone.
Great video. Want to do this in my crawl space attic but double sided. Was considering the Lowes as it’s a little less than Home Depot but almost want to support attic foil because they’re a great resource.
Buy it in February. I bought a double aluminum foil side but single bubble wrap in the middle for $50 for 500sq. Ft. I couldn't believe the deal. Now I can finish my attic. I just did some of my attic for 1 summer and it made a big difference. Now I'm very excited for this summer :)
We used a radiant barrier on top of the attic insulation & it works. I am so happy that we found this product. Highly recommend the product, but do the research.
I live in a certified green house...(though I'm not an adherent of the global warming cult...it was just the way it was built.) It has foil backed roof sheathing and a whole house dehumidifier.. nice for us in Florida. But I still want to do something with garage door which faces the bright afternoon sun and lots of sun here.
Air sealing is the only way to stop the heat moving around. Insulation uses air to get its R value, if you pass air through it the heat goes right with it.
My house gets the most sun on only the back half of my roof. Would installing this foil on half do anything or would the entire attic need to be foiled? Ty.
One of the vids I watched described radiant barriers like shade - every bit helps. That was also the reasoning behind not having to apply things perfectly with no gaps and such - as it's not trying to wrap things, it's trying to act as shade.
Thank you for the video. I think the white on the bottom is an interesting option, especially for areas that are used like a garage. How much of a gap did you leave at the top of the rafters below the roof line? We have a long roof over our garage with rafters down on the sides that lead back to the main area where the roof ventilation area is. Hopefully, air will continue to flow back to the main area. we have cross beams a couple of feet down from the ridge line - I've wondered about tenting across under the cross beams, but so far resisted - any thoughts?
Innovative Insulation in Texas has a product called double bubble double foil that you can layer 3/4” apart in the rafter spaces for about $.30 /sf The white side is only for appearance to give a finished look.
I was watching a video on TH-cam about HVAC ducts, he said ducts in attics is bad idea, temperature difference is huge in summer, R8 insulated ducts are not helping.
Quite true. Running HVAC ductwork through the attic, which is all too common, means that chilled (or in winter heated) air is only an R7 away from a very hot (or cold) attic space. I my case, I solve that problem by putting an additional R7 wrap around my ductwork and putting 16-inches of blown in cellulose on the floor of my attic. That gives about 5 inches of cellulose above my ductwork. It seems to work well enough. Even my most distant vents get properly heated or cooled air. I also used aluminum foil tape to seal up the gaps between the vents and my ceiling so there's no air leaking into the attic. Tape seems to work better that expanding foam and is much cheaper.
So does that mean you really like it I mean you didn't seem very excited about it I've never done anything like this my radiant barrier looks like foil but it's not bubbly so I'm kind of confused I got mine on Amazon just looks like a roll of foil.
Haha, I guess I’m overcompensating for the lack of sleep. With a 4 month old and 4 year old the only time the house is quiet enough to record is midnight. Glad the content was helpful.
I don't understand why, in the South of all places, you put the A/C unit and all the attendant ducting in the hottest part of the house. Every air-conditioned house I've ever lived in had the A/C unit outside the house. Is this a North vs South thing? And if so, why? Or do builders just not do the "A/C unit outside" thing anywhere any more?
I would be interested in the change of temperature between the barrier wrap and the wood sheathing as that may affect a significant rise in heat causing a shorter lifespan for the shingles...
That is interesting. I didn’t think about the heat affecting the lifespan of the shingles. Towards the end of the video I do show the difference between the radiant barrier and the underside of the sheathing. It is almost a 20 degree difference on a mild 76 degree day.
@@GrayHouseStudio I think air movement and the attic heat both affect the lifespan of shingles. That's why attic ventilation is so important. I would be interested in the heat between the barrier and the shething next time you've had some nice hot days...
Here is a video I did back in 2011 Showing that the roof deck over a radiant barrier will only go up 5-10º which is considered nominal. th-cam.com/video/OHpyv_kxmoI/w-d-xo.html
@@GrayHouseStudio I had a new roof put on 5 years ago and allowed the ridge vent. Love it. Just by itself it works great. I can't wait to see the difference with the barrier.
at least your shuts off my AC don't shut off. on a good day it just keeps going and going and going it never shuts off literally I have to turn it off. nothing's wrong with it I got it looked at but then again in all fairness my unit is undersized.
Great video. Im thinking this is the way we should go with our new construction home. Do you find any issues with cell service inside your home? Thanks for your input. Dwight
i was recently qouted 12k to have this very product installed in my house.. only to find out that his $4.35 per sqFT would cost me about $.375 in raw materials
I'm sure you already know this, but an A/C system that "short-cycles" like this is the direct indicator that it is oversized for the conditions (home load compared to outside conditions).
If that every-15-minutes cycling is happening around your peak summer conditions, you'd really benefit from some measures to address this.
Eventually down the road when ready to replace your A/C, you can go cheaper and just get a one-size-lower capacity to better match, or invest in better answer, a higher efficiency unit that includes a VARIABLE or STAGED compressor at full size.
You'll have the capacity to retain the ability to address higher temperatures during hot spells, but gain the incredibly more efficient handling of your A/C during the rest of the year as it runs at lower capacity.
You'll get longer run-times at lower energy use, and it will properly dehumidify the air.
For now, there are also programmable thermostats that allow you to set a wider dead-band and other features, so that you can have it wait an extra degree above setpoint before activating the compressor, and run it an extra degree or two below the setpoint so that cycle times are extended and more dehumidification can be effected.
Also, be sure your thermostat location is away from sun exposure on an interior wall, and is NOT directly in the path of one of your supply air diffusers.
Side note: You've probably already gotten the advice that you cannot get an accurate spot reading of temp with your IR pistol on reflective or bare metal surfaces (paint a section matte black first?).
You may wish to add that installing the reflective radiant barrier like this does block a large chunk of the radiant solar load from being absorbed into the attic, but retains the full airflow from the soffit-vents up to the ridge-vent so that roof sheathing and structure is still fully vented and airflow will actually be better, minimizing any potential increase of temp to the shingles.
This concern about shingle temps goes away completely once you upgrade your roof to a metal one.
Keep up the information sharing!
The a/c issues, could be, from the attic, not being properly air sealed.also may not have enough insulation on the attic floor
Shingle Temps!!!!! 1st Comment I've seen...considering this asset!!!!!
Lower the fan speed, run time will increase, evap will get colder and will help dehumidify
@@markchristensen5206 I’ve used this technology for years. There are numerous products for different applications. A different application is to install the perforated product directly on top of existing insulation and cover duct at the same time if applicable. If not, wrap ductwork with the double bubble double foil (the Mercedes of all products!) This product can be layered in rafter spaces, installed 3/4” apart giving tremendous protection. I get mine direct from the manufacturer in Texas for about $.12 sf. Innovative Insulation. There is a demonstration on TH-cam which is the same one I saw many, many years ago. These products truly work!
Radiant Barrier Is It a Scam
Sarasota Energy Saver video
Make sure to also measure the temperature split between the return and supply it should be about 20 degrees. If it's not try adjusting your blower speed, sometimes they set them up with too high of speed. Fixing this will also help it dehumidify the air.
No one ever compares there bills on here before and after
You can't get an accurate temp reading when using an IR gun on metallic surfaces due to high emissivity. The reading displayed will be significantly lower than what it actually is. Try putting a small square if black electrical tape on the metal and then point the gun at that for a more accurate measure of the radiant energy.
I'm looking to do this barrier install to my house here in Australia soon. Thanks for the info.
Very true, but largely irrelevant here because the radiant barrier he used has a white back, not metallic.
did u
Hi mate. I'm in newy and am thinking of doing the same to my underfloor. Keen to know how you got on.
i believe you meant say it's high reflectivity, as radiant barriers are intended to have low emissivity
The 10 degree temperature difference I measured for my post compared of the surface of the cellulose (shredded light gray paper treated to make it resist burning) to the ambient temperature (down low) of my attic.
Good info. It works! Just installed 2-sided foil- backed bubblewrap (pressure fit, no air gap) inside a couple of kitchen cabinets against the back wall. Did this because our coffee cups would need to be heated with hot tap water to prevent cooling our morning cup of coffee. After a cold 25 degree F night, a cup located inside the newly insulated cabinet was just as warm (same temp by feel) as a cup that sat on the counter overnight in a 68 degree F kitchen.
That stuff is great. It comes with its air gap built in, but works even better installed with an air gap to the outside.
I have a comment about the tip you gave about leaving an air gap so the heat doesn't conduct straight through the radiant barrier.
Even if you have the radiant barrier pressed right up against the wood and the barrier itself gets hot, you still benefit because of an interesting bit of physics: shiny things, which are really good at reflecting radiant heat are intrinsically poor at radiating heat themselves. If you look for physics demonstrations of emissivity, you'll see demos where two metal cans filled with the same temperature water with the only difference being that one can is painted matte black and the other is polished shiny do not look like they're the same temperature when viewed with an infrared camera. The shiny one looks many degrees cooler even though the heat conducts right into the shiny part, simply because reflective surfaces are intrinsically poor at radiating heat.
You can actually get even better performance if you use multiple layers with gaps between them. Have one radiant barrier pressed up against the wood, and then have another with a gap between the two. Radiant barriers are not 100% efficient; a few percent of the radiant heat still makes it through. Suppose the leakage is about 4%. If you have two layers, then the first one lets through 4%, and the second lets through only 4% of 4%, which is 0.16%. This repeated attenuation of radiant heat is how the multiple radiant barriers of the James Webb Space Telescope are able to keep the shaded side at temperatures a few degrees absolute zero (Kelvin scale) while the sun-side gets to temperatures of about 230˚F (383K).
Layering is the ultimate system. There is one type called double bubble double foil that even carries an R-value. Since a radiant barrier is a totally different animal than fiberglass or cellulose, it doesn’t have a measurable R-value as such. Fiberglass is only puffed up air and just slows down the airflow. That’s why it takes so much of the nasty stuff!
i considered the idea of installing multiple layers. but, of course, it is best to do this on a new build. it is exponentially harder to do this on an existing and occupied structure, especially with such awkward and confined spaces. rather, i'm planning to just install one layer on the joist and one on the attic floor. the rolls i purchased are perforated to allow moisture to escape. had i considered radiant barriers earlier, i would've included it behind the vinyl siding that i helped my dad install
I have an 2000 sq ft attic. The sheathing is OSB with a reflective lining on the underside. I then have reflective foil staples to the bottoms of the roof rafters. My attic space is horribly hot. Shouldn't both layers of radiant barrier ellimate most of the heat? Why then is my attic still hot? I have a light colored metal roof screwed directly onto the sheathing. I shrug my shoulders and scratch my head wondering if the reflectivity of these products are worth the expense. My attic should be around 90*, but i know it's a lot closer to 120*.
@@tynyyn5344 Is your attic ventilated? Roof/ridge vents? Sometimes people seal off the ventilation when installing radiant barriers, and that defeats much of the purpose. The heat in the attic still needs a place to escape regardless of type insulation.
Howdy Barry. Thanks for taking the time to reply. I have half of the attic ceiling ventilation blocked off because of calculations used to figure out how many square inches of soffit vents I need. According to the research I did, I only need a certain amount of ridge vent in order to make the soffit vents work properly. Thus I sealed off half of the ridge vents. Should I unseal them? @@barrygrant2907
It's not only the heat from the roof, and attic. it's ,also, 3 more things that heat up your home..
1, holes in the ceilings, from,, The can lights, the ceiling fans, and the heating and cooling, registers. The heat from the attic in summer, comes through the holes. The cold in winter comes through the same holes. I sealed the space between the sheet rock, and fixtures. No air movement.
3, a gable fan that is thermostat controlled. It blows the hot, attic air out.
2, My home came with blown in insulation, no good home got hot. You could feel the waves of heat coming down from the ceiling. I added R13 in the attic. It slowed down the waves of heat, not enough. I then added R 25, for total of R 38, what a difference. No more waves of heat. Yesterday it was 112° outside, our home inside got up to 72°. We have no air conditioning. What we also have is a whole fan. We turn it on at night, when the outside temperature is less than the house temperature. Most mornings the house temperature starts at 64°. We not only cool the house down we coolthe attic temperature as well. The whole house fan cost about .06 cents per hour to operate. At the time of writing this, it's 1 pm, and , 100° outside, and a cool 68° inside, we started the morning, at 64° inside the house.
I put up an attic fan for $40. I got a Vornado clip on fan on clearance for $10 and a digital temp controlled outlet for $30. When the attic gets hot, the fan turns on and blows the hot air out of an attic vent. I'm also about to put up radiant barrier
@@wokejoke2675 I installed radiant barrier, was not happy with the results. I installed R25 fiberglass insulation on top of the barrier, that made the most difference in the temperature inside the house, I'm adding an additional R 38 on top of my current R 38. The gable fan should not be based on price, I use to be price conscious. Now I'm volume of air conscious, the more times you can exhaust the attic air the better, my attic is 7,000 cf. A 1,050 cfm fan takes 7 minutes to exhaust the attic, 8 times per hour. I'm replacing my current gable fan, 1050cfm, with 2,800 cfm. That's roughly 3 minutes to exhaust the attic air, or 20 times each hour. The more volume the faster your attic cools
As a side note, it is much hard to heat/cool very humid air. You can heat/cool less humid air very easily. As an example, look at deserts, their temps go up and down drastically with their low humidity.
I could not believe the difference it made with the method I tried. I found white highly refractive roof paint at the hardware store and painted my flat roof with that. It made a MASSIVE difference. Easily 5-10 Degree Celsius cooler than ambient in the house now. I left a small section uncoated on the roof close to where the ladder was for comparison and the white roof feels as cold as the steel of a pot you took out of your kitchen cupboard and the old paint(Dark grey) is scolding hot.
Now if only we could switch between black and white during the seasons..
@@LightGesture black only will help if the roof dont have insulation. if have some insulation the heat triiying to come in say wtf is this you want me in or what?
@@VostockR it’s also less effective because the winter is cold, because the sun isn’t shining as much in the first place
I've got attic foil on top of my blown-in cellulose insulation and it definitely helps. On a hot day the temperature under the foil is about 10 degrees less. Keep in mind that when it's placed on top the insulation on the floor of your attic the air gap is above it with only a small air gap provided beneath. When it is bouncing up is the radiant heat in hot the attic air.
I have taken another step. To keep the heat radiating from my roof away from the floor of the attic I've also placed a wrap of 4-foot-wide attic foil around the base of my attic. That starts the heat radiating from the lower shingles moving up. On a hot day the air exiting up at the top of that foil is about twenty degrees hotter than the foil itself. That also creates a chimney effect as moving air moves other air up and out of the way. The one weakness is my house is that it lacks sufficient ridge venting, but at least I can push that heat upward where it eventually exits.
One final remark. The foil I'm using comes from Attic Foil, which has a website with that name. It is very heavy duty. You can walk on it repeatedly without tearing. Also, for humid climates you can get a foil from them with holes in it to keep moisture out of your insulation.
Have you noticed any financial benefits? Have you been able to notice a significant change in temperature or how often your HVAC system is working. I have a small home with standard trusses and my easy way would be to lay it on the insulation as well. I hav all fiberglass insulation and really don’t want to crawl into that space anymore than needed.
We are glad that you were able to use the Radiant Barrier, and thank you for the shoutout! DIY projects are the best 😉
We love it! Also, we used some extra we had to survive the crazy freeze with no power for 3 days. We covered all the windows and doors from the inside. Prior to putting it up our house interior was below freezing with the fireplace on. Once we put it up, we could keep the house at 55 degrees with the fireplace. Also, none of our exposed copper pipes in the attic froze. At least half the houses in our neighborhood flooded from burst pipes in the attic.
I would like to get a quote on your product for my residental property.
@@GrayHouseStudio I live in South West Missouri and fernice/ductwork is under the house. A/c is outside and I have big gabel vents. My house has minimul shade would you still tecommend this product of a DIY? Donyou still think its worth installing after having it for so many years? Thanks just price of electricity is getting up there these days in mid 2022
@@ddemier I can set you up with my supplier in Texas. The basic product is about $.12 /sf up to about $.29/sf for the best product they have. You can order it direct from the manufacturer. I’ve used it for many years and in these tough times, I’m trying to help as many people as I can. I’m only passing on great information on a product that truly works. I have used it as a house wrap and in the attic for many years in my construction business. Everyone needs to use this before the shipping lines are totally shut down. Let me know if I can help, and spread the word!
@@rayburnyarborough4695 do you have company in Atlanta that can recommend regarding product
The air gap between sheathing radiant Barrier the insulation. Installed by radiant barrier on my remodel and the space above radiant barrier was 125 degrees and 80 degrees below it. With only a single layer of vapor permeable vapor barrier. With adding 800 Sq ft. Contractor said I’d need a new HVAC. It’s running better than before remodel.
I live in Phoenix, have lived in other climates. My biggest improvements has been insulation and using mini split AC. I furred inside walls so 8" and max attic insulation. The mini split AC allowed for controlling every room separately, no ducts in attic and returns grills.
I had a similar with the air conditioner cycling, and found that it was due to one of the vents pointing at the thermostat. Turning that register fixed the short cycling issue.
Later in the year when the 40k btu air conditioner was on 14 hours a day continuously, I installed a gable vent fan, and the interior temperature dropped 8 degrees even though it was 6 degrees hotter outside when I took the second measurement. Btw peak daily humidity is about 85%.
Been a bit since this was posted, seen your channel is not making many videos anymore. I would highly suggest using a FLIR (even if you buy it, check the areas, and return it soon after) to see if there are air leaks around your fixtures in the walls and ceiling, and even pull apart some of the insulation around the ducting to ensure that there are no leaks in the ducting itself. Checking you have enough soffit vents to ensure no air is being pulled into your house from outside by the heat rising to the top and pulling some air from your house into the attic. I also believe from what I have seen here on TH-cam it is better to have it directly over the insulation. They are made to be vapor permeable, however, if you have it over the insulation itself you ensure no air movement over the insulation that could reduce the R value by blowing through the top few inches. Hope all went well with this as I don't see really an update on it after 3 years.
I put it in mine, and it made my atti and house cooler. I haven't reblown insulation yet, but hopefully, in a few months before summer gets here.
I have lived in a new housing estate (in Australia) for seven years. Every house that I have seen built has the roof sarking and wall wrap fitted with the coloured side out and the shiny side in. I addition the manufacturers advice says to do it this way. I am not prepared to argue the case but am simply stating that this is how it is normally done.
Yeah, that's what I have always thought.
video didn't seem to answer the questions. I would like to see:
- if for a given time period if the AC cycled less frequently after barrier installation compared to before.
- for a given time period, show graph of the attic temperature fluctuations, before and after. Duct temps as well, although I am less interested in that. I just want to know if this has the potential to decrease my AC frequent cycling problem and have data to support it.
It seems like you only pointed the IR thermometer and showed the barrier was cooler. That should translate into cooler attic temps and less AC cycling, but you did not show that. You showed a graph of the before condition only.
Also, compare ac bill before and after
I’m an engineer too, but you fuggtards lack the real question. How did it FEEL!
Thanks for putting this up. Did you see drop in the ambient temperature in your attic? And comfort in your house over the last two years?
Innovative Insulation in Texas $.12 /sf
What an informative video! I use that same stuff in car restorations - awesome barrier inside the car, on the front bulkhead (to reduce engine heat transmission). I also use that stuff for custom car shades.
You likely have your thermostat too close to a vent. It is seeing cold air immediately then shutting off. Try putting it somewhere with little to no airflow from the ac.
Yes!...Bruno
WOW! Great video thanks so much for sharing and taking the time to do this video. Hmmm looks like your last video was 2 years ago, are You all OK?
Haha, ya we are great! We started a business moonrockprints.com and it has been keeping us busy. We haven't forgot about the channel and hope to have the space to make more videos soon. It feels good to have you ask!
Very interesting video. I was hoping you had a follow up video. It would be great if you did one In peak summer heat to do a comparison to this one.
I was also interested in what the summer to summer difference was
Yep, I like this sort of video where real world temp monitoring is done. Your subscribers are curious to see the after effects of this radiant barrier as well as AC cycle and temp information. South Louisiana is BRUTAL this year with the temperatures!!!
I used Atticfoil, $150 a 4'x125'. Stapled(electric) to underside of the rafters. Atic floor measured 130degrees on a 100 degree day. After installing attic floor measured 95, exact same time and conditions. Roll of foil paid for it self in 1 month. I'm saying this because you never really showed the real cost saving impact or even answered your own question.
Yes, radiant barrier works.
I also used a Sense monitor in my house and the first thing I did was install a gable fan and that wasnt enough to cool my attic so the next thing I did was install a radiant barrier in my attic and my attic temperature went from 156F on a 98F day to 112F on a 98F day. My energy usage from my air conditioner dropped 75%. I also turned off the attic fan to see how much it helped and the attic fan plus the radiant is the combination you need
I just got my fan and am looking at putting up a radiant barrier.
Vent fans will cool your attic but they mostly do so by sucking cool air from your living space. It turns out that negative pressure in the attic is a bad thing.
@@Lew114 That shouldn’t be the case if you have an additional gable vent that allows for more air in.
@@Lew114 if you’re pulling air from your living space then that means you don’t have adequate soffit ventilation and also means you should be sealing things like top plates and ceiling penetrations.
@@Lew114 Yep, attic fans are a terrible idea.
If there's a part of your house that isn't being cooled or heated properly-perhaps a child's bedroom or bathroom far away from your central HVAC, there's a useful technique to correct the problem. Overdo the insulation and foil for that room to better equalize the temperatures. Thick curtains in windows also help.
a quick test of this principle is to turn on the stove (high). Use a piece of aluminum foil, hold it between your face and the stovetop (within a foot) and it will block that radiant heat. Use a similar sized panel of thin paper from the same distance and you will feel the heat radiance. It works to stop heat transfer via radiant transfer. Aluminum is a strong conducter of heat though.. Once it touches the burner, it quickly heats up and will "radiate" that heat (as well as strongly conduct it... excellent heat sink).. so the gap is needed,
You should do your due diligence before posting something as ludicrous as this. Radiant barrier is as different as night and day from “tin foil”!
Reading from a box of Reynolds Wrap: to avoid possible heat damage, do not cover oven floor or an entire back…
Radiant barrier is 99.9% aluminum and reflects heat.
Excellent model to explain the effectiveness of the barrier. Thanks.
reflective mylar is a better example. i had small air conditioner unit in my room that ran an exhaust duct to the window. the duct was just a thin tube of accordion plastic that leaked much of the heat back into the room. i took an emergency blanket (mylar) and wrapped it around the duct, then zip tied it.... massive difference to the touch
Here on pacific NW it doesn’t get very hot for long in summer or cold in winter. Very common to have no central a/c but there’s just a few weeks of 95-100 d , so I’m adding this product.
make sure your soffits are perforated and you have a good ridge vent, and you still need to let your attic vent, so you could stick to gable vents for that
6:11 the infrared thermometer test is misleading because the back side of the radiant barrier is not going to have the same emissivity as the wood. For this reason, IR thermometers are not accurate at measuring the temperature of things that have different emissivity. For an accurate test, you need a matte black sticker on the wood, and the same matte black sticker somewhere on the radiant barrier, and you need to do the IR reading on the sticker only. By comparing the IR reading off of the same kind of surface (one with good emissivity, where the IR reading most accurately tells its temperature) your IR thermometer reading will be accurate. If you don't do this, the readings are misleading.
For a good demo of this, you can get two paint cans, paint the surface of one matte black, and polish the other or tape foil tape on it so it is super shiny, then fill both with boiling water. After a minute or so, both cans should be at the temperature of the boiling water inside. Read both using the IR thermometer. You will get wildly different readings though a hand-test (feeling the can with your hand) will show you that the temperatures are the same. This is the clearest demonstration that IR readings only make meaningful comparisons if you read off of the same kind of surface, and if that surface is emissive enough where the IR reading gives a realistic indicator of the thing's temperature.
Watch the video: Radiant Barrier Is It A Scam?
Sarasota Energy Saver for a great demonstration!
Yeah man I do AC work and if your system isn’t removed the humidity it’s either oversized or your thermostat located in the Supply airstream and it’s causing it to short cycle.
Usually it’s just not charged to the correct Subcool/superheat level. Anything under a 17* split is usually not removing too much humidity. However most homeowners never notice the difference. I’m in the Deep South and have never seen mold growing in a attic. Maybe a little in the wet winters but dries up dead as soon as the summer heat bakes it up
@@kirkhernandez1165 An oversized unit will definitely short cycle.
Thanks for the video, yes it was extremely helpful, I'm gonna put the same barrier in my attic this spring.
how has it been holding up over these summer months? (i'm just waiting for cooler temperatures to install my rolls)
If you lower the inside blower fan speed, your A/C will pull more humidity out. From high to medium or next lower speed, I wouldn’t put on low speed as it may cause coil to ice.
Of course it works dude , most Americans use a windshield radiant barrier on a daily basis
Crest Exteriors in North Texas sold us a “radiant barrier” in 2017 when they replaced our roof after a hail storm. NO AIR GAP, making it a waste of money on an expensive underlay. Per LOGAN at CREST, air gaps are not needed, when responding to my telling him the manufacturer disagrees with him. Logan knows best as he has installed 100’s of these per himself. Doing something incorrect to hundreds of clients doesn’t make it right. Crest has refused to do anything about this. Now, a few weeks ago, APPLE ROOFING came to do an inspection, confirmed the radiant barrier is not installed correctly. This is also when I tell them it was installed by Crest. This is when they told me that APPLE and CREST are the same company. I have yet to receive written report from their inspection and no response to emails and texts. I believe in Texas there is a 10 year statute of limitations on construction defects due to difficulty in detecting them. Suggestions are appreciated. They also tore down the gazebo my recently deceased (at that time) dad built without consulting us, and then charged us $1200+ for new one (this was hail damage and an insurance claim). They also accused us of not paying our deductible, which I handed directly to Logan when he came to pick it up at the house.
Hope youve hired a lawyer!
Radiant barrier which is silver on both sides is more efficient, since it lowers emissivity on the lower surface, and so reduces infrared transfer to the attic floor.
I have my thermostat throw set to 1.5 degrees vs 1, that causes it to cycle less, which I think is more important for energy savings in the Winter, but still, less disturbing at night in Summer because going on/off less. Very interesting video, I have reflector on the roof decking but still 135 in attic. Does sound like AC oversized if not running enough to dehumidify.
Adjust your fan speed on the blower. Is gonna help with dehum and use a water pump on the drain line so water doesnt get soak back in the air
I don't know what kind of ducts you have but typical flex duct has it's own foil radiant barrier on it.
The duct barrier only helps when the AC is running. At other times, the dead air inside the ducts is heated up by the high attic temp. The trick is to reduce the attic temp.
@Gray House Studio question on this... I noticed the temp of the sheet of plywood was 140, vs 130 degrees on the 2x4. In hindsight, do you wish you applied a strip of foam tape to the 2x4 before stapling the foil to reduce thermal bridging and keep more barrier from conducting from the wood to foil? Or do you think the difference would be negligible? Thanks :)
the emissivity of the foil is so low that it should not be significant
your ac unit is oversized. depending on what you have you may be able to do some tuning to get better dehumidifying and all around better performance. 15 mins on and off sounds like a cycle setting in your thermostat also. your on the right track though.
Try a dehumidifier, they are amazing for lowering temps
Why would you leave a air gap at the bottom and the top I installed mine all the Way to the outside of the exterior wall plate and then up to and around the collar bracing. I then installed a dual power solar ventilator on the roof above the collar bracing. I also installed 1 x 4 boards horizontally every two feet to allow air to transfer from one rafters to another. End result is air is drawn from soffit vents in and up the rafters then outside by the ventilator. My attic temperature is only a few degrees different from the home temperature. Any opening in the barrier is just allowing heat back in the attic. I can’t figure out why nobody else is noticing this on the internet
From all I've heard if you seal it up it can create moisture especially in humid climates. Hot air would typically rise so the air can be pulled from the gap at the bottom of the installation up and be released through the gap at the top. All the manufacturing instructions appear to recommend the same thing - gap at top and bottom. Not that that's the only way to solve the issue of course as your solution may also work well.
AC is on all the time but not for long enough to dehumidify? Your AC is way too big man
Can you elaborate on this?
An air conditioner doesn't just remove heat it also dehumidifies and if the air rushes over the coils to fast it won't have time to take out the humidity.
Ya it's pronot practical to replace it so probably adding a dehumidifier is probably the play
First try slowing the blower speed when in cooling mode. Usually it is set to medium-high or high. Try reducing it to medium-low.
I've thought about installing a relay with a dryer style temperature switch so that my fan wouldn't stay too low.
I think I could leave the hot side alone if I think about it.
Very informative, nice job. I've been researching this, hence how I got here. Thank you.
Hope it provided some additional information.
We have a metal building that we are adding stick framing to, for a canin. Would we be able to add this reflective barrier along with batt insulation to achieve proper R-value with less space?
It's interesting to know how much energy you have now spent on A/C compared to the same outside condition before installation .
...so how did things go this summer? Is there an update video?
Definitely insulate your attic and your ducts more since they are in the attic. Can only help.
So whats the long term result? Are you noticing your AC not kicking on as much? Has gas this radiant barrier impacted your electric bill? Would you still recommend installing this radiant barrier to a D.I.Y.?😊
Great video. I have same problem , ac takes like 5 hours to cool from 80 to 73, the ac is managing my bill, it is killing me.
I live in Katy Tx and my roof has that feel in the sheeting.
Do you thing the radian barrier will work even if i already have the film on the sheeting? thanks
Hi there, I am planning to put aluminum bubble insulation under the ceiling (leaving an air gap of 1.5 or 2 inches), so it would be wood /air gap /or aluminum bubbles. My intention is to reduce the radiant heat that comes from and through the wood (from the ceiling). Will this work? (I live in San Diego, not a humid place, but temperatures in summer fluctuate around 95 °F.) My second question is: what is going to happen within the airgap? Is it likely to generate humidity and potentially mold?
So how did this work out? Please make a video explaining the results over the last 2 winters.
That would be great.
A follow up on the install.
Watch the video: Radiant Barrier Is It a Scam?
Sarasota Energy Saver
This is the same demonstration I saw many, many years ago and I’ve used it ever since in my business. Any questions let me know. There are many types of radiant barrier products.
I did this in our attic years ago when I was young enough to get around in there!! Also there was enough room to move around in there. I opted for going with blown in insulation in our next house. Zero help in my opinion. If I am feeling frisky I may try the radiant barrier and here. Thanks. It would be great to see your numbers for next September and compare.
If you use white Roofguard 700 on you asphalt roof every other year, it eliminates the need for a radiant barrier and you will have a forever roof. After I applied several layers, my attic went from 145+ midday in the summer to 5 degrees above ambient temperature.
You applied this to your residential home? Just wanting more detail. Say I bought this product and painted my roof on a one story home with an attic and around a 30 degree angle.
@@toolandmaynard My roof was leaking and the shingles were curling up. I used a 3/4" nap roller with a 12ft. pole to backroll Roofguard under the shingles and pressed them back down. I used 3 layers the first time to seal everything. I've been reapplying about every 1/3rd year since. Now it's a solid coat. Any groves I filled in. The downside is snow doesn't melt like a normal roof. My neighbors will have ice dams and ice sickles and then go dry while my roof will just sit there full of snow. So if you get a lot of snow, that might be an issue.
Interesting. I have a couple areas that are weak in my roof and leak slightly. Sealed it with tar haven’t noticed an issue yet. I’ll look into this. The snow not melting is a sign of good insulation. I get what you are saying though. Thanks
@@toolandmaynard Any bad spots I used a couple of layers of 6 oz. fiberglass cloth. The cloth makes the roof dramatically stronger.
I have some insulation material.. one side is shiny & the other kinda has a yellow cotton candy like 3 inch soft material. Would this be good for a dog’s house? My neighbors dogs are outdoor only pets & they both suffer in the cold. The owner only provides them with food. Any advice?
Hello, thank for the video, would you please post a link to the product you used. I don't have soffit vents but do have gable vents, would this still work for me?
Well you are not going to get your attic to the same temp as outside but probably a fan would help to get some air moving thru the attic
So just to confirm you have laid foil over your insulation and you have radiant barrier stapled to the attic? Is the foil you laid down perforated?
ATTACH IN THE ATTIC BY STAPLE TO THE RAFTERS, THAT MAKES THE AIR GAP. OR LAY KN TOP OF EXISTING INSULATION. IF USING THE PROPER RADIANT BARRIER IT WILL WORK. IT WAS USED IN SPACE TO CONTROL TEMPERATURES IN SPACE SUITS AND MODULE
Foil stapled to rafters has another advantage. It channels the heat up creating a chimney effect. That keeps the hotter air away from the insulation above your living areas.
building a home so that the roof is separate from the home, will prevent this issue. Think of the roof as a tree shading the house fully, and the house underneath, it has a 2nd roof to seal off home from outdoors. This way, attic is free to vent all that heat, home is shaded all day.
That was super helpful. I'm thinking of tearing off shingles...laying out some foil product...putting on 2/4 sleepers over the trusses and a new layer of plywood. Forming a cold roof.
tHanks for your insight.
Unless you just need a new roof, I would install radiant barrier either on top of existing insulation in the attic or between the rafter spaces. Let me know if you need any advice.
@@rayburnyarborough4695 tHank you. Yes, this roof is a tear off. So new shingles are the plan.
I want the cold roof for the house, that is why I came across the idea of laying out the foil over the old decking....then adding 2X material and new plywood over that.
Any ideas and advice is more than helpful.
I need all the opinions I can find.
@@rayburnyarborough4695 tHank you very much.
The plywood on the existing roof is just 3/8" (1960s ideas). Rather than tear it off, I will simply make a cold roof and apply another layer. Same money except for the 2X material that will be used as a spacer between layers.
This is how I have an easy opportunity to put the foil on.
Still need opinions, please share any thoughts.
@@Dancing_Alone_wRentals Great! Call Innovative Insulation and talk to Matt Russell. This is the manufacturer in Texas. Their website is a wealth of information and different products. Tell him I told you to call. He can advise you on the best application and you can order directly from him, saving tons of money. I just spoke with him. You might only need one more layer of 3/8 plywood, however it might cost more than 1/2”. The savings on the radiant barrier might allow you to purchase a 1/2” Advantech sheathing. That stuff lasts forever. I always shop around. Try to go with a local lumber supply rather than the big box stores if possible. Good luck 😎
@@rayburnyarborough4695 tHank you...I appreciate the tip!
The insulation will always run ambient more than what the actual room temperature IS...
My block exterior walls that are bare are currently -5F.
The insulation reads 40F. Inside temperature it is 34F.
I have foam board laying around and it's 58F.
I can see my breathe and it's freezing ..
Question is, how much did it cost... and how much are you saving?
Yeah I'm interested in this. I'm just wondering how would you use something like this in a semi truck? It gets so hot inside there's so quick and trying to cool it off. It's hard. Cause there's no way to create a airspace.
Very helpful…Thank you for the detailed summary!
I’ve been spreading the word like wildfire. I’ve used radiant barrier for a long time in my business. I can set you up directly with the manufacturer in Texas and you can order it directly. There are different products for different applications ranging from about $.12/sf to $.29/sf. I’m just trying to help my fellow brothers out. Watch the video: Radiant Barrier Is It a Scam? by
Sarasota Energy Saver for a great demonstration. This is the same one I saw years ago and I think they wanted about $1.50/sf to install. A get rich quick operation. I did my due diligence, as I always do, and found the manufacturer in Texas. The only thing I would get out of this is the satisfaction that I’ve helped someone.
great video, you may want to check out a ductless mini split system when your real to improve your ac....
Equal on and off times equals a 50% duty cycle.
How about squirting water on your roof to cool the house?
Hi, any long term results? Does it help after summer? Is it still in good condition?
IT IS BETTER TO USE THE BARRIER THAT IS DOUBLE SIDED, SO IN THE WINTER IT KEEPS THE HEAT IN AND SUMMER KEEPS THE HEAT OUT
What is the R value of the Radiant barrier that you used? How think was it???
interesting. can you put this over baffles and insulation for extra benefits?
do you EVER BLINK??? LOL, RELAX!!
Never
Great content. How do you know when your shingles are leaking?
Do radiant barriers do anything if you already have faced batt fiberglass insulation?
Great video. Want to do this in my crawl space attic but double sided. Was considering the Lowes as it’s a little less than Home Depot but almost want to support attic foil because they’re a great resource.
Innovative Insulation in Texas $.12 s/ft
Buy it in February. I bought a double aluminum foil side but single bubble wrap in the middle for $50 for 500sq. Ft. I couldn't believe the deal. Now I can finish my attic. I just did some of my attic for 1 summer and it made a big difference. Now I'm very excited for this summer :)
Thanks for the scientific approach 👍
Any update on the longterm savings? I installed it and im seeing some savings😊😊
Mini splits helped us out in our home.
We used a radiant barrier on top of the attic insulation & it works. I am so happy that we found this product. Highly recommend the product, but do the research.
I leave the ac fan on all the time and it works well
It will increase the humidity during cooling season. The condensation from evaporate (indoor) coil will get back to the house.
Yeh. Don’t do that. It increases humidity.
I live in a certified green house...(though I'm not an adherent of the global warming cult...it was just the way it was built.) It has foil backed roof sheathing and a whole house dehumidifier.. nice for us in Florida. But I still want to do something with garage door which faces the bright afternoon sun and lots of sun here.
Company giving me estimate puts it in the floor versus the roof. To prevent the heat/air from escaping or coming in. Said 20% less solar panels needed
Air sealing is the only way to stop the heat moving around. Insulation uses air to get its R value, if you pass air through it the heat goes right with it.
My house gets the most sun on only the back half of my roof. Would installing this foil on half do anything or would the entire attic need to be foiled? Ty.
One of the vids I watched described radiant barriers like shade - every bit helps. That was also the reasoning behind not having to apply things perfectly with no gaps and such - as it's not trying to wrap things, it's trying to act as shade.
Yes. Imagine walking on your roof barefooted on a sunny day. Anywhere your feet get blistered is where you would want to locate the radiant barrier.
Thank you for the video. I think the white on the bottom is an interesting option, especially for areas that are used like a garage.
How much of a gap did you leave at the top of the rafters below the roof line? We have a long roof over our garage with rafters down on the sides that lead back to the main area where the roof ventilation area is. Hopefully, air will continue to flow back to the main area. we have cross beams a couple of feet down from the ridge line - I've wondered about tenting across under the cross beams, but so far resisted - any thoughts?
Innovative Insulation in Texas has a product called double bubble double foil that you can layer 3/4” apart in the rafter spaces for about $.30 /sf The white side is only for appearance to give a finished look.
Install a soft start.
I did not read all the comments but you should have cold air coming out of your supply registers, MUCH less than 70 degrees.
Great video! What temperature sensors/app are you using?
I was watching a video on TH-cam about HVAC ducts, he said ducts in attics is bad idea, temperature difference is huge in summer, R8 insulated ducts are not helping.
Quite true. Running HVAC ductwork through the attic, which is all too common, means that chilled (or in winter heated) air is only an R7 away from a very hot (or cold) attic space. I my case, I solve that problem by putting an additional R7 wrap around my ductwork and putting 16-inches of blown in cellulose on the floor of my attic. That gives about 5 inches of cellulose above my ductwork. It seems to work well enough. Even my most distant vents get properly heated or cooled air. I also used aluminum foil tape to seal up the gaps between the vents and my ceiling so there's no air leaking into the attic. Tape seems to work better that expanding foam and is much cheaper.
So does that mean you really like it I mean you didn't seem very excited about it I've never done anything like this my radiant barrier looks like foil but it's not bubbly so I'm kind of confused I got mine on Amazon just looks like a roll of foil.
Awesome , Thanks.
Jesus dude blink once in a while 😂 Great video very informative
Haha, I guess I’m overcompensating for the lack of sleep. With a 4 month old and 4 year old the only time the house is quiet enough to record is midnight. Glad the content was helpful.
Seriously? That is all you got out of this video? I might be wondering why you're looking into his eyes so much.
@@elainenilsson5472 So Dreamy!😂 Dreamy McDreamerton!!!🤣😂🤣
I did
I don't understand why, in the South of all places, you put the A/C unit and all the attendant ducting in the hottest part of the house. Every air-conditioned house I've ever lived in had the A/C unit outside the house. Is this a North vs South thing? And if so, why? Or do builders just not do the "A/C unit outside" thing anywhere any more?
How are your temps during hot summer?
I would be interested in the change of temperature between the barrier wrap and the wood sheathing as that may affect a significant rise in heat causing a shorter lifespan for the shingles...
That is interesting. I didn’t think about the heat affecting the lifespan of the shingles. Towards the end of the video I do show the difference between the radiant barrier and the underside of the sheathing. It is almost a 20 degree difference on a mild 76 degree day.
@@GrayHouseStudio I think air movement and the attic heat both affect the lifespan of shingles. That's why attic ventilation is so important. I would be interested in the heat between the barrier and the shething next time you've had some nice hot days...
Here is a video I did back in 2011 Showing that the roof deck over a radiant barrier will only go up 5-10º which is considered nominal. th-cam.com/video/OHpyv_kxmoI/w-d-xo.html
@@AtticFoil Thanks for the video and information...
@@GrayHouseStudio I had a new roof put on 5 years ago and allowed the ridge vent. Love it. Just by itself it works great. I can't wait to see the difference with the barrier.
I'd like to know can you give us an update on that please thank you
Thank you, know one believe me about the air gap ❤
how much money per month do you save in summer?
Nice work
at least your shuts off my AC don't shut off. on a good day it just keeps going and going and going it never shuts off literally I have to turn it off. nothing's wrong with it I got it looked at but then again in all fairness my unit is undersized.
Great video. Im thinking this is the way we should go with our new construction home. Do you find any issues with cell service inside your home? Thanks for your input. Dwight
i was recently qouted 12k to have this very product installed in my house.. only to find out that his $4.35 per sqFT would cost me about $.375 in raw materials
The installation process is a bit of work. But I will DIY it😅
Great Video, Thanks!!
Glad it helps.