Living In A Passive House: Theory vs. Reality
HTML-код
- Опубликовано: 28 май 2024
- Casey was invited to speak at the Ottawa Chapter of Professional Engineers - Sustainability Symposium in November 2018. He took the opportunity to talk about his experience living in his Passive House and answer questions from the audience.
You can listen to the audio version only here:
www.theconsciousbuilder.com/e...
Special Academy Offer - How to Market and Sell Passive House
www.consciousbuilderacademy.c...
Apply for a LEAD BUILDER position with The Conscious Builder
www.theconsciousbuilder.com/c...
MORE FROM THE CONSCIOUS BUILDER:
Website: www.theconsciousbuilder.com/
Instagram: / the_conscious_builder
Facebook: / theconsciousbuilder
LinkedIn: www.linkedin.com/company/the-...
Twitter: / buildconscious
CONTACT:
Email: info@theconsciousbuilder.com
Office: 613.693.0914
DISCLAIMER:
Videos produced by The Conscious Builder Inc. are provided for informational purposes only. The information contained in the videos is intended to give general guidance to simplify residential construction projects. Because tools, products, materials, equipment, techniques, building codes and local regulations are continually changing, The Conscious Builder Inc cannot and does not assume any responsibility or liability for the accuracy of the information contained therein. Further, The Conscious Builder will not accept any claim for liability related to, but not limited to, omissions, errors, injury, damage or the outcome of any project. It is the responsibility of the viewer to ensure compliance with all applicable laws, rules, codes and regulations for a project. The viewer must always take proper safety precautions and exercise caution when taking on any project. If there are any questions or doubts in regards to the element of a plan, please consult with a licensed professional.
Large roof overhangs add beauty and protect doors, windows and siding from rain and sun damage.,
Interestingly, when I was growing up in middle-class suburban New Jersey in the 1950s and 60s, almost every “lunch-pail Joe” homeowners had “overhangs” on their windows. They were called “awnings”. Every town had a number of residential awning installers that went out of business when Inexpensive AC became ubiquitous.
This is not intended as a criticism…just an observation.
Interestingly at the White House south facade, President Truman had the “Truman Balcony” built because he hated awnings.
sometimes the simple, obvious solutions are timeless and sustainable!
I like the thermal breaks we install for windows. It stops any thermal bridging.
Awesome to get the straight info on pain points, and what you might do differently.
I've got a small cabin in Colorado that I'd like to practice retrofitting to Passive House standards. I'll not hit the full specification, but will come as close as practical. As I've been planning and getting quotes on aspects of the project, *I've radically changed how I will approach the problem.* Kind of like your revelation about windows and passive solar heat gain.
*First, making the crawl space fully conditioned, and put water, ERV, heat, and solar electronics down there.* Water is there now, but poorly insulated and I have an electric heater to keep it from freezing. I'd need to dig out the crawl space to add a decent floor with 2 layers of OSB directly on top of EPS insulation. But I'd need to temporarily pull out the existing water tank and plumbing. Digging is a problem because it's decomposed granite, which requires power tools. Bigger problem is no water until digging done, the floor installed, and plumbing put back. *Solution, build a pump house around the well and put water storage and conditioning there. Plus I wanted to dig in the supply line and put it deep enough to not freeze.* The crawl space would have no tank and no pump. Still have to dig for a floor if space fully conditioned.
*Second, build a couple of solar thermal panels using a 6-foot wide surplus sliding glass door (which I'll have), and then do something with solar hot water storage in the crawl space.* There's a group in Finland who proposes to use excess electricity from solar PV to heat a vast quantity of sand to crazy high temperatures for year-round heat storage. PV -> resistance heater -> sand? There are far more efficient ways to do things. However their reasoning is that PV panels are insanely cheap. So what if it's only 1/3 or 1/4 as efficient as solar thermal, Finland has plenty of land. Also, much simpler maintenance with only one type of solar system. *Solution, dump the solar thermal and hot water. I want batteries to time-shift the power generation/usage anyway, and LiFePO4 batteries have gotten crazy cheap.*
*Third, I still need to dig out the crawl space for ERV, heat (electric), and solar electronics.* I was planning on super insulating the ceiling and not the roof, but if I shift things around... *Solution, fully condition the attic rather than the crawl space and put the ERV, heat, and solar electronics in the attic.* Probably the least fiddly way to insulate the roof is with closed cell spray foam directly against the underside of the roof deck. Spray Jones (YT channel) says, no venting is necessary, at least by Canadian law. If not supported by local codes I may be able to get a structural engineer to sign off on that technique.
*Fourth, the crawl space has an outside access door, and the attic has an inside ceiling hatch.* This is completely backwards for a conditioned crawl space and unconditioned attic, so I'd need to build new access. Note, think about where your air membrane is and how many penetrations it has. *Solution, if the crawl space remains unconditioned, and the attic becomes fully conditioned, then no changes are necessary, except maybe a nice pull-down ladder to the attic.*
*Other considerations:* Minimize openable windows (cheaper and they don't leak as much air). Insulate walls by removing siding, adding 2 layers of 2-inch foil-faced polyiso with taped seams, then new siding with an air-gap between it and polyiso. Leave the 3 1/2 inches of fiberglass in the walls (did some calcs and given low winter temps and humidity there should never be condensation inside the wall) (total is R-40). Room for 14 full-sized solar panels on east-southeast roof pitch, afternoons are often cloudy so morning production is ideal. And minimal passive solar heat gain with only one window facing south.
The well house is the first project.
hey thanks, good luck
23:15 Lots of people questioning your decision not to use Solar Thermal, lol. The moment the first guy started I knew more people were gonna try to pull you up about it.
Solar Thermal has lots of proponents in the eco/low-energy/sustainable construction world, but the fact of the matter is that it's basically a dead-end technology for the vast majority of the Western world. There are some places where it's supposedly very popular (Israel, I believe), but other than that I can't see any sort of mass-market for it unless there's some breakthrough which brings costs down by at least a factor of 10.
Solar PV has seen such improvements through R&D investment and reductions in cost over the years that it's basically destroyed the (already tenuous) financial benefit of using Solar Thermal. Meanwhile, ST has seen no real reductions in cost and still has key issues that haven't been addressed:
Too many moving parts to potentially break, will never amortise itself over its lifetime, produces too little hot water when you want it and produces too much when you don't want it. Oh, and let's not forget that it's also a one trick pony.
At least with Solar PV you can heat your water through your heat pump, run your appliances, your AC, your lights and charge your EV. If you're gonna pay £5-20k for something solar you'd be foolish as hell not to choose the PV route.
Question: Why two separate ERVs?
Thanks for your input. With regards to your question about the two separate ERV's, it was because of the size of the house. We could have got away with one unit but it would have been running at a higher CFM which would have made it quite noisy.
Makes sense. Thanks for replying!
Solar thermal hot water can be very effective, and a good choice for many. In all of Asia and many parts of Europe these panels are ubiquitous. Our roof-top evacuated-tube panels supply hot water down to minus 25C; below that, the hoarfrost accumulation starts to interfere with solar gain so we rely on the wood cookstove coil. Yes, it can be very expensive if you hire a contractor to install a top-of-the-line system. We designed and installed the hardware ourselves, and used very affordable Chinese panels, heat exchangers and pumps. Yes, more moving parts that can fail. No, control is not that difficult: the setup is designed to supply all the hot water we need most of the time, and an automatic heat-dump diversion valve discards un-needed Btus. I think I WILL agree with you on one point: the cost of PV has fallen so dramatically that yes, water heating via solar electricity makes more and more sense today.
Used to be, pv panels were not cost effective, but solar hot water heating was (for domestic hot water use + space heating)
Absolutely enlightening. I appreciate the honest information. It's amazing to someone who would like to renovate to thus standard.
Thanks so much for watching Kurtis, please let us know if questions come up while you do!
Interesting presentation, I can't believe the 3 of them couldn't get it to net zero, and they didn't have a way to regulate the hot air to make sure the house isn't too hot.
Thanks for the comment.
Cool shit, thanks for the honesty.
Can you please give us cost analysis for Passive house items Envelope, HVAC, windows and exterior doors, Erv system for your 4000 sft home.
thinking about the overheating .. keep coming back to what was discovered when people started doing solar passive houses.. Cement .. while not super green does a great job of absorbing solar and keeping the thermal flywheel effect working. So it really does moderate how hot or cold the house can get. Not sure why they went with the Vfr style hvac it works well but radiant heat actually is more efficient. Dont know that there is much cost difference when you get down to it. 18,000 btu is minuscule amount of heat input, and could easily been installed using a 50 gallon water heater (run off the PV panels). There are now variable flow circulation pumps that would also keep the power use to a minimum along with other on demand hot water circulation so water is not wasted. Roxul (rockwool) is a nice product,but one has to pay a premium vs cellulose to achieve the same real R value. Had to smile at the R value they installed.. because where I live that would be dramatic over kill for the area. Would only take an extra 10 years just to break even on the extra cost. R 60 in a ceiling space would be great but not sure how long to break even.. Thinking about fire resistance.. 2 inches of roxul and then the rest being filled with dense pack cellulose would really do the job more than adequately. Not everyone lives where snow is on the ground 8 months of the year. I have not seen snow much less below 20F very often where I live...
Thanks for the comments!
Considering that more extreme weather is in the works for the northern hemisphere, that extra R might pay back in no time at all.
@@whatsupbudbud once air and vapor are taken care of Yes a bit of extra r value is a good thing.. I have been looking and kind of figure that installing cellulose give one the biggest bang for the buck. Two extra inches is cheap as any insulation that I can find.
Great presentation, and its also nice to see a local person spearheading advanced building methods! I'm wondering why you chose to use Rockwool in your walls instead of a high grade Cellulose, which would have seemed more fitting for a green building? I can understand the worries of potential water issues, but wouldn't a high quality air barrier like Siga Majvest over your outer sheathing take care of that? Currently desiging my own house to a PHS and I'm wondering if the conclusions I reached are another example of "works well on paper, but in reality..."
You also mentioned you did a lot of the work yourself, which I also plan to do. Did you find that building a more advanced "shell" add a significant amount of time compared to building to code? Any major hurdles that caught you by surprise? Thanks
Thanks, Ryan! We decided on Rockwool for a few reasons. We did, however, use Cellulose in the attic. I'm assuming you're talking about doing a Dense Pack Cellulose for the walls. First, there are few people doing this and even fewer doing it at the time we built. Also, Dense Pack Cellulose requires pressure to be built up when installing so we would have had to create pockets within the wall which would have added more time. Moisture was also a factor as you mentioned. Overall we felt that Rockwool was the best "bang for our buck" at the time and provided that added insurance of never having to worry about loss of R-Value or Mold.
Does charcoal filter really replace a Kitchen exhaust fan? When my tenants cook and fry with oil without the fan, every surface on all my cabinets get coated with sticky oil! Then wiping with soap removes the oil stain finish. Murphy oil soap does a poor job. So now $50,000 cabinets have to be refinished! No kitchen fan seems penny wise, pound foolish!
If you are doing a lot of deep frying, you probably would prefer an exhaust. We didn't use a deep fryer and the charcoal filter worked well for us. Other clients who don't cook a lot of greasy food get by great with a charcoal filter!
interesting presentation. In europe (belgium) the norm takes sun h=gains into account but also evaluates the risk of overheating an imposes measures to mitigate. Guess your local code has been updated since...
His house is massive! One of the biggest passive houses I’ve seen. And huge windows.
;) Yeah! Thanks for watching Basia!
You answered a lot of questions. So thanks for that.
With COVID where would you be getting the supplies?
What can be done for shaded homes in the way of retrofitting?
So glad you're finding answers! Most of our regular suppliers are operating during these COVID times, but we are dealing with a lot of delays as man power is affecting the supply chain. We'll try to answer your retrofitting question in a future video, stay tuned!
If you have to put a lot of energy into cooling the building than the house is not net zero or passive as advertised. There is more than one way to solve the overheating problem. A screen of plants that cast shadow in the summer and loose their foliage in the winter would be a relatively cheap solution.
Thanks for your comment. The home does not overheat in the summer months so it does not require additional air conditioning. It was overheating in the winter months when it was well below 0 degrees celsius which can be fixed by opening a window. the overhangs of the roof provide the required shading during the summer months. The house is a Certified Passive House and this presentation was to discuss the fact that there is always a difference between theory and reality.
@@Theconsciousbuilder My apologies! I misunderstood the problem. But doesn't the theory tell you the optimum amount of glazing surface you need for the space you want to build? From what I know, after the design phase is done you can put your model into a software that can evaluate and predict eventual problems like overheating.
@@mariansdraila We don't do the modelling ourselves so I can't comment on exactly what information it spits out. From what I can remember, the software was more concerned about overheating in the summer than in the winter. There's nothing better than experience. Theory is always theory until proven. That being said, I likely would not have changed anything other than not worrying about making sure the back of the house is directly South. Large windows are a nice feature. It's just about understanding the implications of choosing to go with that specific feature, whatever it is.
If the sun makes the interior too hot couldn't you just open a window to let some cold air in and regulate how much cold comes in by how far you open the window?
You could even have some fancy windows that adjusts themselves after sensing a thermostat.
Yes you could open a window absolutely, but the ventilation system is somewhat pressurized so it's not ideal. If you are relying on your air filter to clear pollutants and balance humidity that also throws things off. Those fancy windows sound great, for the right client. Thanks for watching!
How do i add rafter tails or overhangs, after the continuous insulation is applied? Do you have a video?
Matt Rissinger (Build) youtube channel has lots of videos around this there is a very cool system they use to achieve the overhang
What about automated blinds when the sun is above a certain brightness? I've done it for office buildings for almost 10 years.
The sensor is a reverse polarity LED, and the motor controller for the blinds uses two metrics - internal temperature and brightness. I've used Crestron processors in the past but they can be cheaply replaced by Raspberry PI's nowadays.
You of course have to log and tune it a bit, but I usually don't have to do more than 3 basic code revisions after the fact.
We never really looked into that because we were fine dealing with the heat. We preferred the light over blocking it out. A personal preference.
@@Theconsciousbuilder Fair enough. If you had to do it all for the first time and consider DC motor controllers, programming, sensor placement, etc. - it's not worth doing especially if you don't mind the heat.
Where did you put the blinds and control board - outside or inside?
@@whatsupbudbud everything on the inside. Serial controls everything. More modern controllers are moving to power and control over ethernet (PoE). I suppose you could install your temperature sensor externally as well, but that isn't really as meaningful as the temperature inside. If it's winter and sunny it could be comfortable inside and freezing outside.
@@RealityGutPunchShutters being outside is what I would aim for since, no matter how close they are to the window inside, the IR radiation has already penetrated the inside of the house. But thanks.
So a passive house doesn’t require HVAC especially for summer heat? Are there true long term cost savings benefits to building passive houses these days as up front prices seem way too high compared to standard build to code homes?
A true passive house would not require HVAC but it can be nice to have a solar powered option for temp adjustments. There are major cost savings over time! We have more information on Green Building Standards on our website here: www.theconsciousbuilder.com/energystandards.html
Regarding the overheating issue, did the house have any extra thermal mass (like a concrete floor topping) to absorb and store the solar gain? If not, might that have helped?
Hi Dave, that's a great question. We get into this more in our conversation with Ross Elliot here ruclips.net/video/PM3K6hTgUGM/видео.html
There is a lot of talk about the certification process, the odd thing is I've never seen a passive house video that explains why you'd want to get certified - e.g. tax benefits...
Hi Boe, hope this is helpful! ruclips.net/video/PT6BnhJRpNA/видео.html
He spent 70 - 120 thousand just for windows
And he now has 28 degree temperatures inside... so perhaps reduce the amount for a less tropical temperature! lol
How are you using 1000kWh per month in the summer with no electric car? I have a mid century house with improved 2-pane windows and insulation, even with electric cooking and water heating, and a person that is full-time work-from-home, we rarely hit 300kWh per month. For all of that effort put into building envelope and such, you still have sky-high energy use.
We didn't use that much in the summer. If you look around the 22:00 mark, you will see that the usage is 240, 240 and 280 for July, Aug, Sep. However, we can't rely on these readings because I did not have a smart meter. Some months were estimates and some were actuals. You can see that Feb was 480 which tells me it's an actual and they realized they had over charged us for previous months.
Great topic love the accent.
What accent? Haha Thanks for watching!
Ya, what Accent ? Too funny.
27:40 $70K to $120,000 for stupid windows????? Guess what use thermal shutters using 3" R15 foam board and then use regular windows that are 1/10th the cost. Never understood the desire to spend so much on a "high effciency" window that might have an R8 value when a piece of foam over a regular window with thermal shutter.
So, are the bathroom fans pulling in fresh air through the ERV or exhausting through the ERV?
There are no bathroom fans. There is an exhaust duct which is connected to the ERV system and a booster switch. When the switch is hit, the ERV ramps up for a short period of time and changes air throughout the home at a faster rate. The ERV system is balanced so that air leaving the home and air coming into the home are doing so at the same rate. This makes sure that all the air coming into the home is preconditioned by the air leaving the home.
An HRV will remove humidity (like in the bathroom during a shower) and replace it with fresh air in the warm seasons. In the cold seasons, that humidity will be redistributed throughout the house in order to keep the air inside from getting cold and dry.
Trevor Hardy an HRV will not put the humidity back into the home because the core is aluminum. It will exchange indoor for outdoor air and transfer the temperature only. An ERV can do this. It can transfer temperature as well as some moisture.
The Conscious Builder Inc. Oh. I had them mixed up. 😂
Trevor Hardy all good!
22:22 Am I understanding him correctly in 2016 he spent 166 a month on electricity. That's not close to net zero.
Thanks for watching! This home wasn't Net Zero but it was built to Passive House standards. We went a different certification route. The way you live in the home (like if you are also charging an electric car, for example) factors in as well. Passive House and Net Zero are different, though both are focused on efficiency! You might like our video "Why our Passive House is not Net Zero" you can watch it here! ruclips.net/video/imGbTpAGHZ0/видео.html
I find videos like this fascinating, but you brought up the elephant in the room near the beginning of your video. Passive house or other standards are great for reducing the energy consumption of new construction, but new construction is a tiny fraction of the housing. I think the bigger challenge for architects, engineers, etc is how do we go about reducing the energy consumption of the millions of existing homes, and how do we go about funding it?
Agreed! You may enjoy some of our other content focused more on density, zoning, financing and retrofits :)
@@Theconsciousbuilder Thanks, I'll take a look.
4:55 r20 batt with 1" exterior... the building code really doesnt go far enough...
can't you just open a window if its hot inside during the winter?
Hi Frederick! You totally can, you just lose air quality control and sound dampening at that point, and you're potentially using more energy to keep the temp comfortable. Your ventilation system will no longer be balanced, so the house may not operate quite as efficiently as intended.
You absolutely can shade East and West windows with vertically oriented devices.
Yes that could provide partial shading but also blocks the view. If you don’t need the view and want to get some light, this is definitely an option.
@@Theconsciousbuilder Not true. There are many types; fixed, adjustable, and retractable for example. You can maintain views and block all direct sunlight. It is all about design. There are no limitations.
@@Adm_Guirk Thanks for the comment.
@@Theconsciousbuilder You're very welcome. Check out eggcrate shading devices. They combine horizontal and vertical fins.
Maxx The Meta-Physicist McGerk could you link to good examples? I’m currently designing a home where the predominant view is west.
hydraulic turbine ? did u consider ?
Mitsubishi mini splits weren't better than heat pump
An older life long farmer here in NC died way into 90's used radiant floor heating in 3rd home absolutely roast toasty in 2.5 feet snow blizzard usually never cold in NC winters which can dip to teen temperatures or in snow blizzards below zero beautiful spacious real ranch home 2k sq ft home 3bd 2 ba home.
No bathroom fans? Really? So showers longer than 5 mins are out of the question because otherwise you get tons of moisture. Then you get eventual mold esp in a tight home.
Correct, there are no bathroom fans but there is better ventilation than a bathroom fan. Each bathroom has an exhaust that is connected to the ERV and each bathroom has a booster switch. When the booster switch is turned up, the ERV runs on high for the length of time selected. It works better than bathroom fans so you can shower as long as you want.
Look at this rich guy who can afford air handling lol. We have transom windows and no ac
The so called certification standard is nonsense as well as alwyas focusing on stickbuilt as the standard. One can achieve a much healthier version without all the fuss of air tightness and mechanical ventilation .
Example . i have built well, helped build two houses in germany that perform equally as well as a certified passivhaus with out the certification .
It’s as follows -
13.5 cm thick solid untreated raw wood on the inside either CLT or block / log walls .
On the outside of that , 14 cm thick wood fiber semi rigid interlocking insulation board with taped seams and vertical furring strips screwed through the insulation and into the wall . Wood siding on top of the furring strips , although you could just as easily do stucco. This create a vent channel for any moisture coming out of the house or going in .
Triple pane wood tilt and turn windows and wait for it . NO mechanical air exchanger .
The most important aspect with no air exchanger is that ALL materials MUST be non toxic / off gassing , including all furnishings , bedding etc.
The wood walls are left unsealed so the hygroscopic effect of wood can operate which regulates the moisture in the house .
Fresh air is achieved by opening windows during cooking or if it seems stuffy , which is extremely rare . The house only needs to be heated every second day in sub freezing g temps .
mecanical ventilation is amazing, what's the point not to have it when building a new house , pasive or not ?
@@superbecx “what’s the point not to have it when building a new house ,,,”
Because windows open and it’s just one more mechanical device that one
has to maintain and ducts collect dust which then has to filtered and the device must be cleaned regularly etc. Just open a few windows .
@@siriosstar4789 you can live in a cave if that's your thing , nothing wrong with erv , it's actually amazing , fresh filtered air all the time in all the rooms
@@superbecx What kind of ridiculous deflective nonsense are you playing at ?
I suggest opening windows and you equate that with living in a cave ?.
Idiot!
I appreciate the input and back and forth but would appreciate it if we can all play nice. We’re all entitled to opinions and don’t need to be disrespectful towards each other. That being said, my opinion is that opening windows is fantastic when the temperature is right outside. Where we live we have hot humid summers and cold dry winters so opening the windows will waste energy because you will later need to cool the home or heat the home more than if you had used a mechanical ventilation system which uses the temperature leaving the house to condition the air coming into the house. With regards to the filtration, this is especially important if you live in the city. Opening the windows where there is more pollution may not be the best idea if you can have a way to filter the air. In terms of maintenance, other than changing filters regularly, there’s not much to them. Some models will have filters that can be cleaned and put back in. In terms of the certification, it’s really up to the homeowner whether or not they want it. In either case, I believe a target is very important so you know what you’re hitting. The certification is proof that it was accomplished. If there’s another way to prove it, then perfect!
Unfortunately he whispered...
In theory we could settle on Mars, in reality we can only travel within 3000mls radius. Thats it.
Every home and business should install a rain water collection and storage system along with solar panels.
Even in areas where rain is infrequent it is crazy to waste the little rain that does fall and waste it.
We need to stop planting green lawns and switch to local native plantings around homes.
It is crazy to plant lawns and build golf courses in dry desert areas. We waste too much water and electricity.
the future is electric. Wind and solar energy along with electric vehicles are the future. Stop using fossil fuels. There is a climate crisis.
Question: If Passive House doesn't care about the methods and materials used, why on earth are all Passive House Builders using CRAPY Wood Frame Construction, OSB is not our friend? Why not just build with proven Airtight Systems, are Passive House Builders brain dead, we have many excellent Concrete/Frame Composit building systems. My personal favorite is the Styro framing system.
George if I wanted to learn more about building a passive house where would I look?
I think it depends on where you're building and what your priorities are. Ultimately concrete and petroleum based products are really bad for the environment and if somebody is looking to reduce their carbon footprint, they will be looking towards natural products. Budget is also a factor. At the end of the day, wood can last well beyond our lifespan if done properly.
@@Theconsciousbuilder Wood might, but OSB is not wood and let's not pretend it is ;) Also, concrete is not flammable, look up statistics on house fires in wooden-framed homes vs brick and mortar houses. Also, with global warming causing the temperatures to rise quite a bit, fires starting for literally any reason, wooden houses are going extinct in this century.
Notice 90k views & 1k likes. Reason: poor presentation. You are not communicating complete thoughts, nor are you are not demonstrating your points. Ex: Show us the layers that comprise the outside wall and explain what we are seeing.) Instead of asking if people have heard of (whatever), assume someone has not and explain. Ex: For those of you who don't know what a passive home is, it is a home that meets specific federal regulations. The basic requirements are...) Much of your personal additions, while probably meant to endear the audience had the opposite effect. I hope this helps. You know a lot that people want to know, you just need to communicate more effectively.
Thanks for watching Jeff! This is quite old, learned a lot since then but always appreciate constructive feedback.
why does the house need to be so big?? A real North American mistake.