Spray Foam Insulation and Electric Wiring - Just the Facts!
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- เผยแพร่เมื่อ 4 มี.ค. 2021
- This is a detailed look at a ULC test from 1998 on the heating of electrical wiring inside spray foam insulation. The second half I cover practical installation points from our vast experience.
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According to the national electric code any time you have a long continuous load LCL you must derate the conductor maximum capacity by 20 %. An LCL would be loads such as an oven, wall heater, pool pump. If a heater is rated at 20 full load amps then you must up size the conductor to # 10 wire gauge. This is a non issue.
Great insight! I will pin this comment.
NEC also limits the maximum current on the breaker at 85% of the rated capacity. I understand why the testers might want to test to the limits of the breaker/wire, but they're violating electrical codes to do so.
@@jay_321 another thing to consider is ambient temperature. My background is in medium voltage distribution, large power transformers are rated by ambient temperature. A transformer in alaska and the exact same transformer in Saudi Arabia, their output is as much as 30% different. In the cold, the ambient temperature helps keep the circuit cool even if it were to exceed the standard ampacity rating. The opposite is true in incredibly hot areas. There the transformers are derated due to ambient temperatures. In a barndominium in Ohio heating loads, ovens will all be assisted in colder months
This is probably why the first study used 13 and 16 amps.
First I am not against spray foam at all. I think this is a problem that any high performing insulation can have; but as the one of the highest performing insulations spray foam may be the worst case. @@SprayJones at 24:50 you say (paraphrasing) "its not normally a problem, under normal conditions, with normal wire gauges, and normal breakers, and normal use cases." The problem is that UL, CSA, NEC do not intend to protect users in just normal conditions but also unnormal conditions. A few weeks ago in the middle of the winter storms my parents boiler failed. They plugged half a dozen space heaters in to outlets in their house to keep from freezing; and then ran them for 2 weeks until they could get their boiler fixed. A normal breaker is rated to run a 2kW space heater non-stop. A normal 12 AWG wire is rated to run a 2kW space heater non-stop. What is not normal is high performance insulation. Now I am sure my parents house had no issues with the wires in the wall overheating because it is an old drafty house with very poor performing insulation. But based on the information you presented I think it is very likely with 2 weeks of continuous use in a home that was spray foamed, if there was not an immediate problem, that there would have been a level of damaged to the wire insulation that would have caused problems later on.
The more information you put out gives people peace of mind using spray foam.
Thank you for doing this.
Will do, thanks for watching.
Mike Jones always on point!
I've watched a few of your videos and have been very pleasantly surprised by the depth of information and genuine information without trying to oversell stuff. Thanks for what you are doing, earned a subscription from me and any future business if I am in an area you service
Wow, thank you!
I’m literally roughing in my electrical right now for my tiny home. The timing of this info is impeccable. Much appreciated!
Glad I could help!
I'm in a similar situation getting ready to upgrade my attic insulation wanting to do spray foam on my ceiling 🤔. Thanks for your super informative vidjeos
Very informative, Definitely worth people know these facts.
Glad it was helpful!
Great informative video. Thanks for sharing.
Glad it was helpful!
The more of your videos I watch the more I want to do spray foam when I build my next home. Even better if you could do it!
Excellent, then we have achieved our goal!
Tip: I use only metal back boxes. Behind every box, I add Fire Barrier Moldable Putty Pads. This closes off any rear and side box penetrations. It prevents foam coming into a box. It goes that extra step beyond basic bldg codes, and helps reduce acoustic transfer and the potential for air transfer in/out of a back box. These do add a small cost to boxes, but it is a tiny cost for an extra increase in acoustics & fire safety.
Right on!
Fire Barrier Putty Pads I use are inherently Intumescent. Should ever an electrical device begin to fail, overheat and create hot gasses and possibly ignite into a fire, the Pads are designed to swell up, strangling off the escape of hot gasses inside the back box. These hold the promise of stopping flame spread. If a fire occurs TIME it what you need. Perhaps this might inspire a new Spray Jones video demo?
Smoke detectors have come along way, but they primarily make noise. Most all commercial buildings have sprinkler systems. For homes often these are not required. Some codes require homes to have Fire Extinguishers, but if you are sleeping, or away, these do nothing to put out a fire. For residential Kitchens, Furnace & Living Rooms, Circulation spaces, and sometimes Bedrooms, a Dry Type Fire Extinguisher flush mounted into the ceiling will do more to stop a fire than anything.
There was a time when Cars did not come with Seat Belts. Theses used to be an option. Many died before improvements made.
Building Codes represent a minimum. Forget the minimum. Always go beyond the minimum. The added cost for life safety is always worth it.
Electrician. Connecticut
You covered it all
Just the facts. Just the facts
I just finished the rough in wiring of a house. I put the whole 2nd floor lighting on one circuit and did the calculation on it. If everything was turned on at once, every light and fan, it would pull between 6 and 7 amps because of the low current of LEDs.
Hey Spray Jones! Love your informative videos! I am looking at insulating a 12×20 loft shed, I have just finished the wiring, and am getting ready to insulate! My question is, can I use the 600 board foot double can at home depot, or is it better to get a pro in?
When I contacted a pro, they said you HAVE TO PAINT IT? is this true?
Thanks for the thoughtful comment. My question is... Do we know what temps are reached when the NM cable is run through other insulation types? Carefully cut and fitted rock wool, etc? I see the potential problem with spray foam for circuits that expect heavier use, but how much more of a problem is the spray foam than other insulation?
Great video. One load that does hit the really long load times is electric vehicle charging. Charging at 16A, 240V could easily run 12-18 hours. I think it's still very safe even in foam but that's the longest continuous load I can think of. Charging an EV really exposes flaws in existing house wiring - it's almost always a failure/mistake in the circuit wiring the charger is plugged in to.
Thanks for the info!
EVSEs require derating your circuit (in the US anyway), as does any load that will operate for more than three hours. I just installed one that can pull 48 amps. The conductor and breaker are sized to 60 amps.
Thanks! 🙂👍
I’ve been a sparky now for 23 years, you can’t argue with the results, I will say however it is difficult to dig wire out of foam if it needs to be rerouted or reworked. Using a chemical to dissolve the foam could damage the outer casing of the wire. I’ve always been very Protective of my wiring and spray foam has never really settled well with me when it’s applied directly to my wiring. Now if it’s in conduit that’s a different story. I really appreciate this video thank you very much for putting it up.
Thanks for watching
Can I ask a bit of sparky advice? Building a skoolie, gonna use a combo of spray foam and foam board, I plan on using a 12v system but through conduits on the walls exposed, functional design sorta, but my question is this. Should I always opt for using a lower gauge wire to never have to worry about overload? using a 10 instead of 12 or 14 for the load from solar and lithium battery setup? Are there lower gauges for 12v or just a set gauge? Not sure if that falls in your wheelhouse but any info is good!
Nightmare is not the word couple days ago I went to make a spade hole into a basement dug all the foam out thinking it was safe nicked a wire with the spade and boom fire out of the wall. All because of this special oven wire that was hidden in foam I didn't see. Dig out all foam people no matter what ! You don't know what's hidden.
@@latenightdadjokes9193 Good idea, foam adds to work hours.
These are the best. I am still no sure where I stand over outside the wall insulation vs spray foam but you have my attention. By the way, I was a E-10 electrician for many years. Bob
Hello.
Thanks for watching
Good information. Thanks.
The results of those two studies is odd though. The first is missing some details so a little difficult to prove the exact similarities, but the wire is likely centered and they probably used 120V.
What I struggle with is they state it took less than one hour to cool back to ambient temperature. That also means it should get to steady state temperature while heating in about the same amount of time and that the 12 vs 24hrs time difference should be irrelevant. Intuitively that makes sense as well, as it just isn't going to take a full day for the heat of the wire to heat up the foam. Foam doesn't store much heat (being mostly voids/gas), so heats up to steady state quickly.
But then they are getting vastly different temperatures for only a 2 amp difference in current between the tests. That doesn't make intuitive sense.
Doesn't mean there is a safety issue, but looks like those studies need to be redone. one of them has some variable that wasn't mentioned, or was done incorrectly. The power is nonlinear, I^2*R so 18 to 20amps makes for about a 22% increase in power that has to be dissipated, but the conduction rate is linear. The temperature change should be roughly 20% as well to match the power increase, but is nearly twice the temperature in the second case.
at about 9:20 of vid the test voltage AC was shown at 20 Volts AC? seems like a typo but in the US we use 120 volts. or is 20 volts AC the standard for testing? thanks good video btw.
Can you tell us about your face sheild and air supply system? Do you use sheild tear offs when you're spraying overhead? Where can you purchase? Thank you for the informative videos.
Buy transparencies via amazon and make your own.
Great channel content... if installing mini split... put line set interior or leave outside?
I prefer look of interior but didn't know if you had specific experience with this.
Thanks for your content
I have no idea what mini split is...
Strongly suggest you keep them outside. I've had to gain access to them to clear blockages in the drain line. When it's time to replace them, it's far easier to replace the gas lines if they are outside. A number of manufacturers make nice looking covers. I've even taken a plastic downspout, slit the back and placed all the lines inside. Nobody ever realized it wasn't being used to drain the gutter.
Hey Mike
Any info on the affect that spray foam has on the wire or wire insulation itself during the application process. We get asked on occasion but I explain we apply a thin pass to insulate it first then we can add more because of the heat generated buy thicker lifts of material.
If you read between the lines of the CUFCA ULC test the wiring insulation is NOT damaged by the install of 2 inches of closed cell SPF. Therefore stick to the recommended install and you are OK.
First of that you so much for all your informative videos on spray foam. I have learned a lot on both closed and open cell foam from a general contractor stand point. I have looked through your library on something on sound absorption on spray foam. In past years we have been using Rockwool in the stub bay to help with sound absorption between rooms. @Spray Jones What is the differences between open and closed cell spray foam on sound absorption? Looking to improve on sound absorptions between rooms. Any suggestions would be appreciated. Thank you
Very good question that will be a video in the spring some time. Too much to type here.
@@SprayJones Thank you for the reply. Hopefully early spring? The reason is we are going to be starting 2 very large homes north west Texas the start of summer. I have them putting in closed cell throughout. I just need to know which spray foam will be better for sound absorption because the customers have requested that. I really don't want to have to put addition sheets of drywall or the use of foam boards. Thank you again.
Fire walker,
Unusual name, I bet that’s a whole different story..
Anyway regarding RockWool,
I thought that product is made with formaldehyde...very Bad Stuff....
Don't use spray foam for sound control as it does not block sound waves. Lot of contractors are ripping foam out of walls between adjoining walls between multi family units. Therma Tru tested fiberglass doors without foam and found open panels provided better sound control, but the doors need the foam for energy performance.
In response to your statement that the maximum load for 24 hours not being realistic: I'm retired now, but I was the Fire Marshal for our city and we were always finding overloaded circuits. Granted most were not at capacity for 24 hours but some of them are. We found many power strips plugged into another power strip and then into the wall and most of the available outlets on those power strips being filled. That was with one outlet on a room circuit all the wall outlets in the room have something plugged into them. Most of the appliances that are plugged are presenting with a very low draw so they are instant on. However, we also found a TV playing on the same circuit as a "gaming" computer (gaming computers typically have a higher draw than you standard computer) as well as phones that are charging, tablets that are charging, and they leave the room with everything running. The older the home the less likely the electrical circuit was designed for all those devices to be connected and being used. When questioned we frequently were told "the circuit break kept tripping." I'm not trying to say every building is going to have this occurring but it is more frequent than you realize. I do like your video's and I am learning from them; you give the data behind the code, that gives your video's more clout.
Thank you. People do stupid things.... insurance and safety railings....
@@SprayJones That's why the codes are the way they are. To protect people from themselves.
Hi...great information ...many thanks for all your hard work..really appreciate it, question to you
I am building a garage and will heath it with hydro...walls are 2 X 6...I would like to put durospan GPS R5 4 foot X 8 foot sheets over the OSB walls (tapping all the joints) on the exterior then have a minimum of 2 inches closed cell foam sprayed on the inside as I want a R25 wall....is this a good way of going about it ?...will I get condensation in the inner cavity, Thanks Dave (in Ottawa)
Your method seems fine. We have done many buildings that way. It is a commercial type solution.
Please watch "how much foam do I need."
You can blow the bank, but why when less is more with SPF....
@@SprayJones you are too good.....many thanks for the quick reply from all of us who study every syllable that comes from vast years of study and experience in this stuff.....understanding your busy schedule. You are really helping Canadians keep their homes, their families, and their hearts warm in these cold climate zones...you are a gem....best regards
Mike what’s your opinion of spraying closed cell over light attic mold?
Kill it with Javex and then spray over it.
Interested to know what kind of 12 AWG wire insulation is available to act as heat shield embedded or close proximity of closed cell foam.
I do not know.
Starting my research on spray foam insulation. Planning on building a 40x60 metal building and was trying to decide if i should place all my electrical in and spray foam it or wait until after it is sprayed. I live in south louisiana so its HOT and humid here! Any suggestions? Things i should do or dont do?
Watch most recent video.... when should I do my elec...
I’m new here and I’ve already learned a lot. I watch marshal remodeling. Thanks for doing what your doing. I live in Ohio . What or who do you recommend in lower states for rig buying or companies on where to get the best machines and purchasing the foam. I’m in the construction field at this time and would like to explore that field (sprayfoam) thanks
I have no idea.
Thanks for watching
LoL, if you watched his previous videos, he says how much he hates the "jack of all trades, master of none" person who buys a cheap machine, then undercuts the professional foamer.
BASF is a major foam supplier. Call them. I'm sure they can hook you up.
Look up Equipment Options Direct. They are in KC Missouri, I have their rig 7 years now. They are also in Florida
About the heavy load rating, I am not an electrical expert, I’m just throwing this out there. Are they attempting to simulate a short circuit situation or a circuit that someone, say a homeowner, may have put too many fixtures or outlets on, causing the circuit to over heat? Otherwise, it makes little sense to me to over amp the test circuit. Any thought?
It is. Good analysis.
Thanks for watching.
How do you feel about products such as akfix and other canister applications
Reluctant. It is like golfing with 1970s equipment. Can be done, but at what trade-offs?
Hello, Mr. Jones, from America, everyone's dirty uncle as of late. On a serious note, really enjoyed my algorithm leading me to your channel. I enjoy your presentation, speaking manner and forthrightness. forgive me if you've been asked this but I am building a skoolie, raised roof. I was wondering after watching this, I purchased two, Froth Pak 200 sealant units with the kit. Now I see there is spray insulation by the same company. My question(s), is the only difference between them the fire barrier chemistry? Necessary for RV insurance? Are the viscosities different? I'm worried it's more like the cans and not what I want. The R factor on them both is approx R6 at 1", which I was planning to supplement with 3/4" hard foam board on the interior after spraying, giving me approx R-14 =20ish? is that ok for multiple, reasonable climates?We also are going to have a 12k mini split and most of my wiring will be in conduit in a functional design exterior on the walls so I hope/assume the heat transfer will be minimal. I also multi coated the entire interior metal with Gardner Elasto and will be putting Henris tropicool on the exterior of roof. So many questions, sorry! I've heard and seen some real horror shows and want to be as informed and prepared as possible. Look forward to more videos and knowledge! Thanks
Get all of the inside done by a pro spray foam company. Don't mix insulations it will only bring more issues.
Getting good SPF done is just as important as having the right people elected. Get a commie, and you will have hell on earth.
Hey just out of curiosity is there a type of bidding site or website where you can find jobs or people are looking for spray foam?
Nothing that works or is worth the time.
Have you had any problems with adherence to zip r sheeting?
No
just had my house spray foamed, best decision i ever made-last night it was 44 outside and it was 72 in house with no heat on.
What thickness? Closed or open?
@@jepito29 closed cell three inches and we chaulk all seams before also
So maybe a thin 1" behind a panel and then bat insulation to stuff it? If insulation is required behind it.
What is the desire to use glass fiber?? Build the system to get what you need with SPF.
In Canada, why are "flush mount" panels surface mounted and often rotated 90 degrees?
Some idiot electrician was hung over...
Can you reuse spray foam or does it end up in the landfill?
For example, during a renovation, I simply remove the rockwool batt, add or remove the electrical wiring from the structure , then simply putt the rockwool batt back in place.
With spray foam I have to chip away much of the foam, then afterwards, another company needs to drive to site to respray or I have to try and foam it myself.
Rockwool after many years can be pulled out during a renovation and reused. It's still in perfect condition. I don't see it being done with spray foam.
Also during renovations, wires often get damaged because the spray foam has such a tight grip on them. One turns into an archaeologist trying to remove items embedded in foam.
Sometimes electrical panels get moved and many of the home runs need to be pulled back and relocated to the new location. When it is all embedded in spray foam is can be a real challenge to relocate.
I think 2 or 3" exterior insulation using foam boards or rockwool, with interior rockwool might be a better overall design.
But it's debatable I guess.
No reuse.
The info is flawed . While 15 and 20 amps is the maximum allowed current draw for 14 and 12 awg wire. You have to go further into the electrical code. First the code only allows you to use 80 percent of a circuits maximum ampacity. Seconr any circuit that will be on for more than 3 hrs falls under a continuous load factor. Continuous loads are calculated at 125 percent of the load. So a 10 amp continuous demand is the highest any good electrician would ever put on a 14 awg wire.
If I was going to use foam, I Think I would install conduit (EMT). This gives you flexibility to replace or upgrade the wire. But, that's just me.
Im not a contractor or an electrician.
But it makes sense to me
Conduit is the way i would do it.
Electric car chargers could be a great selling point in the future.
Well, most people wont run such a loads on a standard wiring, with an exception that somebody decides to put their EV on a standard socket and allows it to go to the maximum (and has a parge battery pack) - then it's easy to perceive how the constant current could be maintained for several hours when charging from low battery. (please don't take it as being anti spray foam, I think it's pretty good solution !)
Worst load in a house might be a kitchen.
Most things are LED now. Especially if they are foaming.
Anything else. I would say the circuits are broken up enough to not even see 75% load.
Thanks for watching.
why dont you spray beyond the 2x4 and cut it back flush
Watch "how much foam do I need."
Funny. “Only a moron would spray right up against a panel”. I guess the company who did my spray foam are them. I wish I could show you pictures of my two panels.
Thanks for watching. Plenty of them around...
Water conduits - who knew.
Is that from condensation?
Correct. It is an air tube. If the conduit is in the middle of the insulation you will have frost and water at some point.
@@SprayJones Thanks...!
Your channel is probably the most informative specialty, trade specific, building science information being produced
@@RJ-sr5dv Thank you.
Yo why is your spray foam purple
BASF's trademark color in Canada.
These tests do not replicate any real world conditions.
First off, most heavy loads have an initial spike in current during start up. For example, a table saw or other electric motor rated for 15A will reach 14.XXA for about a second during start,m then reduce current to 10-11A for continuous use, unless it is in stall or dead short, which would lead to exceeding design parameters and tripping a 15A circuit breaker, stopping all laods.
Even for resistive loads the resistance in the conductors increases with temperature and current will drop slightly with prolonged use.
This means that in almost all cases a 15A load will not be continuous in a 15A rated device, circuit or breaker.
Another factor is derating of devices and circuits. Breakers are designed to run at the maximum rated load continuously at high ambient temperatures, 40C I think, and not fail or trip.
Most times the devices and circuits will be designed to run at 75-80% of that rated capacity.
They should never have full load continuously.
So it's all BS.
Now the other way.... often electricians will install circuits parallel and in close proximity in a wall, which means two heavily loaded circuits side by side may heat each other up.
The tests are good enough for code officials. Now bugger off.
What about those Bitcoin miners.... You don't think people are consuming power at 12 hrs. consistently, those mining rigs are working weeks at a time under full load....
Covering high current wiring with spray foam is a REALLY REALLY BAD idea. Typical low current applications are low risk, however MOST of the high current and high temperature worst case conditions have a high probability of failure, fire, and possible deaths. For safe design, ALL the worst case areas need to meet minimum requirements, normally with a significant safety margin. Using spray foam over high current circuits fails those tests without question, especially when high currents and high ambient temperatures are combined.
Temperatures above 90-100C sustained are generally not allowed in contact with combustibles, as charring or ignition may occur. Foam encapsulation of wiring in contact with wood studs and OSB is a serious safety issue with wiring reaching temperatures above 90C. So the "safe" 95C test at 23C ambient was NEVER safe to begin with. And certainly goes way beyond safe when ambient rises above 23C to 50C. Wood charring occurs with a long term temperature near, or above 100°C, weakening the structural integrity of that material, even if ignition doesn't occur.
Most PVC wire insulation formulations are good up to about 100C. Above 100C the PVC structural characteristics degrade, including the ability to cold flow, allowing conductors which are compressed or stressed to short over time.
Rick Kephart's (ex Fire Marshall) comments about over loaded circuits causing fires is spot on, with space heaters and window AC units. Both of these can create near continuous high current loads. The heat produced in the wire is current squared times resistance, so small changes in current produce large changes in power. 13^2=169, 15^2=225, which is a 33.1% increase in heat produced inside the wire, and 18^2=324, 20^2=400, which is a 23.4% increase in heat produced inside the wire. There is a significant difference between the two test reports because of this, and multiple fatal flaws in the test and how the results are being used in this context of foam insulation over high current wires.
John Wolgemuth's comments are also spot on .... "The problem is that UL, CSA, NEC do not intend to protect users in just normal conditions but also unnormal conditions."
Breakers are a thermal trip device, and when placed in a cold area (outside exterior wall) with cold temps (below zero) they will trip slower allowing a higher over current, and much higher inside wire temps when insulated well. Thus higher probability of high current wiring fires during cold and hot weather. As noted 14 gauge wire (and a very cold 15A breaker) can pass better than 20 amps for a while ... 400/169 is 137% higher heat produced in the 14 gauge wire when overloaded from 15 to 20 amps.
The obvious design flaws here are based on thermal conductivity and thermal runaway, combined with thermal efficiency of foam insulation.
First, the test assumes all the thermal dissipation in the text fixture is through the foam insulation to the wall, when a significant portion of the heat can be carried by the copper wire to the edge of the test fixture ... copper is a near perfect heat conductor, even at a small diameter and a distance as short as a foot or two. An accurate test requires more than a 4' test fixture, or multiple interior loops with the copper wire.
Second, the test assumes copper wire and does not define results for high current aluminum wire from the mains, or used for high current sub-circuits as found for sub-panels, and high power loads. Foam insulation of high current aluminum wiring can quickly result in thermal runaway.
Third, NEC 310-16 Allowable Ampacities of Insulated Conductors is based on no more than 3 current carrying conductors in free air, with an available thermal sink to handle the BTU's (Watts) produced. As soon as 1" of spray foam covers the conductors, in excess of 70% of this NECESSARY thermal sink is gone, which is aggravated significantly if multiple current carrying wires are in the same bundle -- IE multiple wires with the same routing, or near a load center, trapped inside the same highly insulated heat locked area.
Fourth, both cited tests failed to quantify and accurately control the amount of insulation (thermal isolation), and there is a huge impact between 1/2", 1", 2", 3" of foam over the wires. This is the same issue as your video about foam depth in the walls, and diminishing returns. It really does mater SIGNIFICANTLY when the wire ampacity goes from free air, to 3" of foam insulation.
Fifth, copper wire resistance increases with temperature 0.393 percent per degree C near 20C, which is 27.5% more heat/power at 90C, and 39.3% at 120C. When the wire is well insulated, this results in a rapid thermal runway condition where the wire gets hotter, produces more heat, and gets hotter, till the wire fuses and/or starts a fire. This is significantly worse with Aluminum wire.
All of these numbers rapidly rise when ambient becomes in excess of 49-54C (120-130F) on a hot summer day without AC cooling. The "safe" 95C in the 15A 14AWG test, suddenly becomes MORE THAN 30C higher, something well over 130C after adjusting for additional resistance heating in the wire. Even in "cooler" areas with 38C (100F) summer days, the west facing exterior walls will have sunlit surface temperatures in excess of 50C in late afternoons. Window AC units in west facing rooms, will push 15A wiring buried in 1" of foam well in excess of 120C, especially when there is pavement re-radiating heat along the west facing exterior wall. These are REAL and often common worst case design points that 10's of thousands buildings face every year, and sometimes every day.
I'm an electrical engineer ... the physics and numbers are important to understand these failures, and resulting fires that do kill people sleeping on cold nights, or hot nights. If you want to spray insulation on high current wires, you had better make sure your insurance policy will cover not only the structure loss, but multiple deaths ... the plaintiff's attorneys are likely to hire a consulting engineer to present these same facts to yield a very high payoff.
Is your business profitable enough to demo and retrofit all of the high risk installations of foam over potentially high current wiring? Do you have enough assets if court mandated? Will you be able to sleep at night if multiple children die in these fires?
Ha, now I want to build with 2x8 framing and high temp wire. jk
Read the pinned comment first.
piece of cake afterwards lol...seriously this guy has never tried fishing down a wall. just trying to sell his product.
Yes I sell my product. I pay my mortgage because of it. But if I pissed off every trade that came in afterwards how easy would it be to sell my product after years of that testimony getting around??
I am a veteran of the SPF industry, what I offer is real insight not theory, keep that in mind when you accuse me of cheap BS.
@@SprayJones did you fish wires down the wall get up in the attic or down in a crawl space and fish wires in?? If not then you have no idea how hard it is to fish in spray walls.
reading a report is not really a show
Then move on.
And reading a text book is not learning....