2023 - Why you SHOULD and SHOULD NOT Build a Passive House
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- เผยแพร่เมื่อ 2 มิ.ย. 2024
- If you have ever wondered about the Pro's and Con's of Passive House - This video is specifically for you!
0:00 Welcome to Passive House
0:40 Why you SHOULD
15:35 Why you SHOULDN'T
I built house nearly 15 years ago (a different era of low energy buildings)with an aim to get as close a passive house as possible, paying some extraa money, but no crazy money. Imhave tripple pane windows, 300 mm aircrete walls with extra 160mm EPS insulation. I have very high heat accumulation due to concrete floor and sealing which keeps nice climate. I measured where I stand based on used energy and it came out as 2.5 times the passive standard with ERV unit temporarily decommissioned (needs rework). I want to build a house extension and certainly in passive standard, with 450mm state-of-the-art aircrete plus insulation, etc. It make sense to go passive these days.
we are doing extension Reno, does it make sense to do passive Renos? or do as much passive as you can afford?
@@Vgallo In my unprofessional opinion, you should go passive if you can and to the extent you can. In Europe it's not difficult now and not costly. I guess that if you're in the US, the situation might be somewhat similar to what we had 15-20 years ago, when the triple pane windows were just taking off, HRVs weren't that common, etc. These days triple pane windows are standard here, every company does them, it's main stream, much cheaper. Double pane being considered budget. So do some ROI in Excel and see what makes sense, either from financial, or from comfort or from ecological point of view for you. I'm planning a house extension and for that I want to go passive or as close as I can. I put costs and U (R) values into excel sheet and found out, that seemingly the most expensive aircrete block (Ytong Lambda IQ) is the cheepest option out of the all aircrete, concrete and clay blocks, when calculated per unit if insulation value. I want to do a "flat" concrete slab roof with green roof and that might certainly be among more expensive options, but makes sense for me and I'm willing to invest into this solution. God luck with your choices!
This was an excellent talk. I think you've pretty much said everything that needs to be said, in weighing the Passive House pros and cons. For us, in central British Columbia, Canada, cost was certainly a consideration. We were willing to spend the money on great windows, loads of insulation etc. But the architectural and auditing fees are very, very high. In addition, local sub-trades are old-school and unwilling to learn new skills. That means supervising their every move, all day, every day. Who is going to do that?
My wife and I decided to design and build the very best home we could, using the information available from Fine Homebuilding Magazine, the Green Building Advisor, Build It Solar, Home Power Magazine and of course the internet. We designed an 1,100 sq, ft. rancher with double-stud, 12 inch thick walls, triple-glazed vinyl windows, raised-heel trusses, air-tight crawl-space and blown-in cellulose insulation. We used a pier-and-beam foundation instead of a traditional poured concrete foundation. We have large, 3.5 ft roof overhangs to prevent overheating in summer. We have R-36 floors, R-48 walls and an R-68 ceiling. Tremendous effort was made to ensure air-tight construction throughout. We have rainwater catchment off the roof devoted to flushing the toilet. We're fully off-grid, with a solar system in a nearby service building. We have evacuated-tube water heating panels on the roof combined with a coil in the wood cookstove. As we built the home entirely by ourselves there were no labour costs. It came in at Can$55 per square foot NOT including the solar. So there you have it: the best home we could build using very good materials, but not the best that money can buy. We use approximately one-fifth the energy to heat that our neighbours do, and no air-conditioning.
Could we have done better? Absolutely. We could have spent far more money and bought much better windows. We could have built sixteen inch thick walls instead of 'only' twelve. But overall, with the information and the funds available, we built a fine home that performs about as well as we had hoped. Somehow word got out about our project and we occasionally get calls from complete strangers who come over for a tour of the place. The local papers have written us up. But the best part of this home is simply living in in. Even at minus 35C we let the fire in the wood cookstove go out before we go to bed, and relight it in the morning. We almost never, ever keep the fire going all day. Our friends keep their fires going around the clock for the entire winter. A dozen years later, we're very pleased with our work. So, as this video says, you can still have an AMAZING home without necessarily going the Passive House route, even though I have great respect for the PH program and ethos.
when someone comes into this kind of thing at the start this kind of ball park discussion is invaluable. i have a 1965 double brick house we just bought in Adelaide Australia. I want it to be as efficient as possible within our budget. Passive home ideas and net zero methods are what will inspire us but what we are starting with isn't that efficient but we will try!
Excellent, thorough presentation. Thank you!
You are very down to Earth. Respect and many thanks
Thank you :)
Great video! Super informative
Loved your presentation and your passion really came over. good job.
Wicked well done!
Well done
Thanks. 😊
You can always adjust the size of the windows, which will improve the overall performance of the house
I don’t understand. Why pay the extra money to get audited and certified? Just to pat yourself on the back and get a certificate?
It's a measurable marker of quality that you can hold contractors and subs to delivering.
@@tyronegrandstrandwill it increase the value of the home?
There are banks who will give you a higher mortgage when you buy a well insulated house!
So if you can show your energy costs are very low, you can pay more on your mortgage.
So yes, they are worth (a lot) more!
@tyronegrandstrand those who work with passive house nuts, charge 2 more times than regular contractors . Passive house doesn't make any sense. I think he was pretty clear about that
Without the certification and auditing you can’t be sure the quality and performance is delivered by the contractors.
If you trust your contractors and they can work using PHPP without being audited you don’t need it. However, if you don’t and you want a fabulous house, it is worth doing the certification to make sure.
Also, if you sell it, the certificate proofs the quality is there. Some people who want to be sure the standard is achieved will pay extra for that certification.
Thanks for this video! I’ve been considering a self-build. It would be on the smaller side and I really appreciate your perspective on all this!
You totally can do it! If you keep the insulation on the outside of the home, and have great water management layers you should be able to keep your home energy efficient and durable.
a quick guide..
Aim for
R-5 Windows
R-10 Slab insulation
R-20 Basement walls
R-40 Above grade walls
R-60 Roof. (unvented is best)
This will get you in the ballpark.
If you are doing a build, I recommend you take a look at doing a virtual training with Dr. Joseph Lstiburek from www.BuildingScience.com his training is excellent and he will walk you though ways to do it that will keep your assemblies out of trouble. Tell him Brandon from Kelowna sent you.
@@levelupstrategies thank you so much for the additional advice! I took a screenshot so I don’t lose track of the recommendations. Those numbers seem very reasonable and achievable for my climate zone. I will definitely want to pursue training so thanks for that as well.
Thanks, fantastic overview. I'm an ex sci/math teacher and you actually use some of my techniques. OK, I live in Taos, NM, both heating and cooling needs. And... was gonna build my second passive solar home but couldn't find land with water rights in time so bought a 1000sqft wanna-be PH but need to add a bedroom and make some adjustments (e.g. The ceilings are wayyyy too tall!) In Taos we rely on wood stoves for winter heat (the last design (walls of pumice-crete) uses 1/2 cord of wood for 1800 sq ft home). Wanted to come in at 1/4 cord for the next house. But man, one cloudy winter day's burn is 88 kWh. We're not gonna touch 15 kWh per sq meter per year. And in Taos we use lots of thermal mass (usually adobe) I wish PH could be done without electric motors, but I don't see it, cuz HRV coupled with the airtightness is the core of the PH model. But that still means burning wood. K, thanks for this intro. I learned a lot quickly.
Great job of plus and minus. I think at the end of the day, a client builds what they want to build. Some care about costs, some do not. My wife and I are retired. Our costs keep going up, but our pay checks do not. Anything we can build or do to hold our future costs is smart. I am an engineer and do not need some organization for approval of what I want to build. We can only build what we can afford and will not feel bad about that. We are doing ICF walls and SIP roofs, but very excellent dual pane windows as the triple panes are double in price. No return on investment there. We will have ERV, dehumidification, variable refrigerant, and additional fresh air controlled off of pressure diff. (positive interior), Merv 13 filtration. We live in a flood prone and hurricane area. I think we will be quite satisfied with our build and at a price we can afford. I want our home to be able to demonstrate what can built for anyone.
That sounds great! I'll bet many folks would love to view a video tour of your home when it's done. I know I would.
The 15 kWh per square metre per year makes sense, but do you get certification before you have proven it over a 10 year. Assuming that you may go above or below in different years
Love your videos, I'm very new to this space in terms of concentration, but I have been reading overviews of it for a while now.
Just wondering, in your view, what are the more important parameters to stick to, air changes, internal temperature, energy used, energy needed etc... And are there compromises that can be made to become passive in accordance with your standards, e.g predicted air changes from the
build vs energy used to power an HRV system to condition your air.
I'm from NZ and we are implementing changes to the thermal envelope standard required R-Value of walls and ceilings to increase, by doing so increases to frame depth and by proxy, cost, client must incur extra costs to implement these changes.
Just wondering if there are other mechanisms that can be used to implement these changes without crippling the market.
I think that the golden age of buildings will coincide with nett zero consumption homes but I do feel there are many ways to skin a cat, but am not sure whether there is room for nuance in the housing industry.
Thank you for the question. I'll take a run at it, and let me know if I miss anything.
In terms of "most effective" energy saving solution - it is Air Tightness - hands down.
The best way to do air tightness is from the outside. The clear polyethylene with acoustical sealant, behind the interior drywall is an approach that is commonly used, and produces significant consequences for the home and the occupants (I have done other videos on that)
The reason air-tightness is the most effective is that if you keep the air that you have paid to heat or cool from escaping out of the house... you save a lot of wasted energy.
As opposed to an ERV - that is 94% efficient vs 86% for example.
Next would be the thermal insulation in the walls ---> without thermal bridges.
Here is a quick and effective guide to get you most of the way to Net-Zero
If you aim for:
R5 Windows
R10 Slab
R20 Basement Wall
R40 Above Grade Walls
R60 Roof (Preferably unvented)
If you consider building materials inside your budge that get you these numbers - you will be in the ballpark for a very efficient home.
Tradeoffs will be just that - tradeoffs in total home performance. But whatever you do, just make sure that you pay attention to the drying potential of the your wall and roof assemblies, so that they can evacuate the moisture that will inevitably accumulate in the walls from time to time. If you don't, your very expensive, well insulated house - may develop rot in the walls - and I don't want that for anyone!
I feel like the kWh/m^2/yr unit makes alot of sense, since you pay electricity in the EU by the kWh and measure the house footage in m^2, so that number can be directly represented into the maximum cost of climatizing a house (actually I think it's 15 for heating and another 15 for cooling so double that at max) for a given electricity tariff. I calculated for my house (which is small) and it sets the limit at around 150€ on the simplest electricity plan, which is crazy, given that's around what it would cost right now to heat a single room for a month!
For the USA, It's best to say it the other way around "per year, per floor area, only so much energy needed", that way it shows it's annualised, size rated, and minimal heat.
There's 10.7 sqft per m2, so it (15kWh) drops to just 1.4 kWh (a one bar (1kW) electric fire for one hour and 24 minutes for the whole year, or 1.6 minutes per week!)
Very few would know and I would still question the person who thinks they know what 15 kWh per metre is in person. As you said, its science and verified and you use the PHPP software for exactly that reason, because I don't need to know what it feels like, I just need to know it was calculated and it happened (certified).
Helpful video, thank you. Do you build in Ohio or know builders that can meet these standards? I hate to be the ginea pig for a new builder to learn from.
Doug, I know that there are lots of motivated and smart trades professionals out there. I would do 2 things - go to a local high performance builders gathering (in Kelowna we have a "building science and beers" meet up monthly) so that you can meet people and start to build context for what you want to do.
Also PHIUS (passive house USA) is a great resource. They will have a directory of certified professionals.
All the best!
Can you make Passive Log Cabins?
In a short answer - no - not without a lot of additional effort. Logs typically only have a specific dimension that does not add up to R-40 walls.
You could however insulate the outside to R-40 with mineral wool for example, and let the logs remain as an interior wall surface.
That would be totally doable, but add extra expense.
What did you have in mind for your project?
We have an old log cottage. Log buildings are terrible inefficient, and I would never build one in a climate that requires heating. As Level-Up says, you could have a log surface on the interior, and a proper super-insulated exterior. Or the reverse, logs on the outside and a beautiful super-insulated interior. But it would be a tremendous amount of work. That means additional cost. We considered doing the first: leave the logs as is on the interior, then building a new exterior. It wasn't worth the projected cost. We left the building alone and accept that it's a low-performance structure.@@levelupstrategies
It really sucks that all the ways to reduce your expenses are so very expensive. Not being able to afford to live cheaper sucks! The people who need to save money the least are the only ones who can afford to reduce their expenses.
Anyone ever seen a high performance or PH with A-Frame construction?
I have not seen one, and the volume might create tension in the calculations on heating demand, but it should be do-able with exterior insulation on the top of the A-frame and good detailing.
I would be curious If the model would allow for large window sections in the ends of the home, because of the R-60 roof/walls. - which would be a beautiful detail.
If your PH build fails auditing, who pays to get it up to standard? The PH designer? The architect? The builder? Who is financially responsible for meeting certification?
In this case, I believe the owner still bears the cost. Although, I can expect the pressure would be on the builder if it failed. The design needs to be pre-approved for performance modelling, the Builder will need to build it to plan (and presumably monitor trades to keep the quality up).
But the owner will need to fund that level of auditing from the builder - it is not something that a typical builder will do, or would be included in a standard construction contract terms and conditions.
Maintaining Passive House standards through construction comes from a deep-passion to build a very energy efficient house. - it's a heart-choice that is backed up by the wallet.
@@levelupstrategies Thanks for your reply. I meant more like, what if the model/design was wrong or if the design wasn't built properly.
I like the idea of passive house, but it seems like there's very little assurances for the homeowner at the end of the day, and maybe that's why some forego certification and just say try your best.
If a designer and builder say they'll try and meet a certification, but they won't agree to it in a contract, that seems a bit odd, especially since the whole point of getting certified is verifiable performance--with the emphasis on verification.
Then again, I suppose it isn't much different from other projects like when a contractor and local government go back and forth on who's responsible for a bridge that can't hold its rated load
@@tubulartuber What I hear you saying is.... if a project is built, and then doesn't meet the Air Changes Per Hour target of 0.6 for example.... who pays?
I do imagine a conscientious builder would be engaged in trying to solve the problem. collaboratively. The final adjustments may end up adding cost for the owner in terms of materials or labour.
I imagine the talk would be something like, “ I could use these much more expensive windows/thickness of insulation/attic layout, or we could save cost and risk it not passing auditing”
If the owner went with the lower cost, they’re responsible
Build in the Aero Barrier cost. You might need it anyway if it’s a complex design.
PH is properly for cold countries, it's not for tropical countries as Asia. As all facilities is also designed to meet with thier application such HRV which is designed for high differential temperture.
Add a dehumidifier for tropical areas if you’re using an HRV
A plaque hanging on a wall is meaningless
What you need is a Hydro bill over a five year period. That has zero energy use.
"The same all around the world".
Over-simplification.
Disagree?
Then please explain the differences between Passive House and PHIUS.
So if I am planning on building a home in Harrisburg, PA with just under 1000 sqft are you saying I shouldn't consider a passive home?
Sorry. Not more lumber. And not fiberinsulation. Tji joist356mm full of cellulose. And 8cm Installation with Rockwool inside. No Problem.😏👍🇩🇪. What are you waiting for? Certification in germany is:: reine Geldmacherei!!!
Rockwool heats up in hot summers!
No, no, no. Rockwool is simply one of many insulation options. It is a thermal barrier. It slows heat transfer in either direction. This means a warmer house in winter and a cooler house in summer. If your home, insulated with the product of your choice, overheats in summer you have bigger issues: too much glazing and inadequate roof overhangs are the main culprits.@@gerritwillemvankeulen3907