Multifamily Passive House in Vancouver
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Even in Italy and Spain, it’s extremely rare. As long as you don’t use plywood, it’s perfectly possible to live without ac.
It depends a lot on the area though: it's uncommon in the north/west (where temperatures get pretty low during the night even during the summer), but not in the south/east where temps won't go below 25ºC for several days (and nights) in a row.
This sounds like mainly the air cooled down while a lot of heat was still trapped in the building itself. There are ways to make this better though. So you could say that particular building is not overly well designed. 28°C is just too much. Though no matter what you try, unless you're under ground, if you have 10 or more consecutive days with temperatures rising well over 30°C, you won't really be able to stop that. Anyway it's been a while I looked into this but some things I recall: a lot of mass on the roof, like a garden, will keep much of the heat out there. More mass in general as well IIRC becasue it just takes longer to heat (but again, once all heat is in and it's too much, you're going to have to wait before it is all gone again). Avoiding direct sunlight on the walls also helps. Reflecting glass, outer blinds (blinds inside doesn't do all that much, that's basically too late because sunlight has entered the interior already).
At my (architecture/research) office, my colleague coded a 3D FEM to model the way this interacts with different geometries so we could investigate how to regulate the thermal storage capacity of a PCM surface. I'm fascinated by PCMs, although he seems to think that the resulting temperature dampening is too little[1] to have broad application in architecture...
[1] Liquid -> gas phase change has a higher latent heat of fusion and might be a way to solve this I think. It would require larger volumes, or a way to safely contain higher pressure, but similar to fridge or AC systems, this should provide a couple of orders of magnitude greater heat storage.
[0] https://issuu.com/passivehouseplus/docs/ph_uk_issue_23_digit...
by the laws of physics, if you have a passive house kind of house, you will not be able to come home to a hot house repeatedly.
Also, all power used inside the building must be dissipated somewhere. In a very well insulated building even just 500W idle power inside quickly adds to the air temp.
furthermore, there is no need to omit windows on any side, even the south side. typically, a shading structure is placed that blocks direct sunlight during the warm seasons when the sun occupies those seasonal positions in the sky. these shading structures do allow sunlight when the sun is in its cold season positions, when sunlight is appreciated inside. going even further, windows should filter out any light that is not within the useful spectrum of visibility -- this reduces heat load from the sun. movable shading can also be used to block the sun only during the warm season.
there are countless examples of houses that have lots of windows and do not get too hot.
moving on to power. the back-side of your refrigerator should be vented, not exposed to your inside environment. led bulbs produce very little heat. overall, as i have said elsewhere, you will always need some amount of cooling and heating capacity.
it remains true that a properly implemented passive house will not get too hot, despite your shortsighted observations.
In hot and stable climates it’s probably common to not have large windows to the south, but in places where you have +30C in summer and freezing to -20 and dark all winter it’s hard to architect for all seasons. I wouldn’t give up the 4h daylight in my south windows in winter, even though they make the house too hot in summer. Shading that can be removed is probably the answer.
Vented rears for freezers, how does that work? Do they typically sit in an outer wall, or do they have ducts venting so they can be placed anywhere? I have never heard of those.
not venting heat generating appliances inside the house is a design flaw and does not follow passive house principles. because nobody addresses this problem, i do consider almost all passive houses to be incorrectly designed and implemented.
the reason why this problem is not addressed is because some degree of cooling capacity is usually present and can keep the house cool despite this flaw. the heat load from the appliances is relatively small and so it is overlooked -- small compared the loads encountered in old-style houses. also, heat generating appliances are a benefit during the winter, so the problem only exists half of the time.
in an ideal system, all heat generated by all systems in and around the house would be channeled and utilized correctly. we are coming closer to that goal.
I know several people with top floor apartments that regularly come home to 32°C apartments after work in the summer. Summers here are hot with little air movement and even sleeping with open windows it's impossible to get it cooled down in the night.
If I didn't live in a rental place I would definitely invest in air conditioning.
Windows also work differently here in Germany than in the US, so the same models definitely wouldn't work. I'm not sure if there are versions for our windows.
Northern Europe, no; but in Italy they're now very, very common. Temperatures there are steadily rising. Italians used to mock countries where AC has long been de rigueur (North-Africa, South-East Asia etc), but now it's a basic necessity - in areas that already felt very hot because of high humidity, they now hit 50°C year after year.
As I think someone else mentioned European/German windows are different to American ones. American ones, lift from the bottom up I believe and an AC unit is put in the gap. European windows can be tilted to be slightly open, or completely opened up into the room much like a door [1].
There are Window units I believe but the Windows have to be modified for them I think, so it's more of a permanent change.
There are also freestanding units which have a hose to go out a window but I've been told from several people that they're not worth the money / don't cool the place down enough. And because the window has to be slightly open for the hose to aim out of more heat keeps coming back in.
[1] - http://4e9dsh1squ2a41o9at4bz989-wpengine.netdna-ssl.com/wp-c...
http://ec.europa.eu/eurostat/statistics-explained/index.php/...
http://www.heidelberg-village.de/
I’m not totally up on my passive house knowledge but it seems to me that the passive house community might have some complaints about this block of pretty conventional looking apartments calling themselves passive houses. I see no effort at all in controlling summer thermal gain [except for some extremely narrow solar awnings]. Are they using special window coatings?
Edit: and my god, all of the floor to ceiling windows in their publicity shots are on a street that faces southwest. Of course it’s gonna be hot in the summer. And those trees won’t solve the problem for thirty years.
But there's something still off about it. I'm not sure what I expect a multifamily unit to look like but the fact that this one gets complaints of being too hot doesn't surprise me.
And in that case it's not just about controlling the solar energy that's coming in, but also having an actual cooling strategy, like natural ventilation, or night cooling.
what was the outside temperature? I live in a fairly normal, cheaply-built and poorly-insulated canadian house without AC and in order for my house to get up to 28C by the end of the day it's got to be about 35C outside. It seems hard to believe that a building specifically designed to be "passive" could perform worse.
Fortunately I was working from home, so I would catch a screw-up early (when I'd realize that I was starting to sweat because of the temperature).
Winter was interesting too. The trailer wasn't all that well insulated, so the furnace had to run a fair bit. But on sunny days, even in the middle of winter, you could really feel how much the sun contributed to warming the place up.
It was an experience that really drove home the concept of solar gain though! If I were still living there, I'd be putting up carefully angled awnings to reflect the sun during the summer but still let it in during the winter (when it's lower in the sky).
We were fortunate enough last year to still have quite cool nights; even if I screwed it up, opening the windows at both ends of the house would cool the place down quite well over night. The only really awkward part was when my wife would come home at 6pm, and she'd be uncomfortably warm until it got dark (which wasn't until 10:30pm or so).
https://www.cnbc.com/2017/05/17/apples-new-office-will-refle...
Generally speaking, money invested in improving building efficiency will have a better carbon and financial payback than any form of solar, wind, or hydro. And yet, homeowners will get solar panels before they insulate their walls.
Under "Bausubstanz & Energieausweis" it lists the energy required to heat the apartment in kWh/m^2.
(I don't live in Germany, but have been considering moving).
Passive solar / solar hot water heaters let you have the best of both worlds with ~zero monthly heating costs and plenty of fresh air.
Depends on where you live I suppose.
I was talking with my landlord a couple weeks ago about solar water heating (surprisingly rare in Arizona being the desert and all) and he said he looked into it before but it would cost more than gas due to all the bureaucratic hurdles put in the way -- which explains the rarity I guess.
http://www.energysavingtrust.org.uk/sites/default/files/repo...
Don't get me wrong, we need stronger building standards and better insulation. Especially in the US, where we let literally any hollow twig+glue structure stand with essentially no quality checks whatsoever.
But the reason everyone "throws a solar panel on top to get Net Zero", is because it gives you cheap green electricity to run both heat and Air Conditioning. There are precious few places you could build this thing in the US where it won't be annoyingly hot to live in for at least 3+ months every year. Even in Michigan, a building is essentially broken if it doesn't have AC, if not for the heat then to at least remove the moisture / humidity / condensation built up.
MVHR seems to assume outside air is always cooler and fresher than inside air, and uses that for free cooling. Which is great for like 70% of the time. But what about the ~30% of time when it isn't there.
You don't have a dehumidifier. One of the biggest benefits of fabric first is the reduction in complexity.
I'm also going to guess that the MVHR is also not 100% efficient. It's either going to create heat to completely cool down the incoming air (hey, look, an AC, complete with dehumidification), or the incoming air is going to average out with the out going air, creating an increase in temperature.
Plus, all of those bags of mostly water are going to be expelling heat, too.
A decent MVHR runs at double figures in terms of watts, so like an old fashioned light bulb.
That's not something I claimed.
Most people in the US are only using AC in the summer (or warm season), to remove humidity from their home when the humidity outside is much higher than indoors.
So during the winter houses that aren't incredibly well sealed need humidification more than they need dehumidification.
During the summer it gets quite humid even when the temperature isn't all that high.
That's not what Passivhaus is.
A cooling requirement, like a heating requirement, is dependent on the performance of the house. Part of Passivhaus is the 'fabric first' approach which delivers performance which massively lowers this requirement, in some cases eliminating it.
As already posted, ventilation solves the IAQ problem.
insulation and air tightness afford the house the property of staying the same temperature on the inside regardless of the temperature on the outside, more or less. if its too hot or too cold outside, this is something you always want. heat recovery ventilation gives the house the ability to move old air out of the building and new air into the building while not changing the temperature of the air inside, more or less. this is why its called heat recovery (also it could also be called cold recovery). this solves humidity problems.
the end result is a house that will tend to stay the same temperature, whether that is hot or cold. in an ideal model of this kind of house, you can see that heating and cooling costs are reduced to almost nothing because you simply choose a temperature that you like and simply never think about it again. this is the origin of the "passive" component of "passive house." with a passive house, you simply dont need a large hvac system. and there is nothing stopping you from adding a modest solar system to your passive house to get to net zero -- it is done quite frequently.
But how is that initial temperature determined? If the house is built in a area during a time of year where the average air temperature is about 85F, then will the house always be too hot? How does it get cool (or hot) in first place?
Climate dependent of course...
You must have fresh air to avoid CO2 poisoning. If the outside air is a problem, then you either 1) give up on being passive and use conditioning of some form or you 2) begin the suffocation process (starts with poor concentration then moves to headaches).
This is one reason for NetZero as an alternative form of building. Even using a solar array with an HRV (Heat Recovery Ventilation) or ERV (Energy Recovery Ventilation) helps a lot if you don't want to run a full compressor-based system.
Most homes leak plenty so HRV's are mostly about recovering costs and helping with condensation and humidity since they are designed for cold weather.
I mentioned that HRV's are essentially standard where I live, which is in Canada, so I think our largest concern here has to do with condensation which can quickly become an issue in any non-drafty indoor space in our extremely cold winters. If the HRV is not set high enough in the winter, ice will build up on the inside of our windows and then melt into the wall structure, causing potential issues.
That is rather sophisticated by North American standards for multi-family housing.
I was stunned when I first saw multi-family houses being built in American as a simple wooden, skeletal structure.
My choice for something like that would've been steel frame with thermal stops for non-load bearing walls, non-removable formwork out of something like MGO board, and foam concrete pour. Not much separate insulation required for this design.
One important thing: always ask for MgO board with MgSO4 binder. MgClOn ones can turn corrosive due to minute manufacturing procedure deviations.
Foamed concrete:
https://en.wikipedia.org/wiki/Foam_concrete
Made in two ways:
1. You mix polymer or protein foam into concrete.
2. You mix bubble generating chemical into concrete that will expand it after the pour.
It is a tricky and rather obscure tech mostly used across the former bloc countries or places that used to receive Soviet tech like India. Working with it is much more of a skill rather than science, and this hampers its adoption.
Biggest roadblocks other than skill intensity:
1. Corrosion protection - porous concrete is obviously more permeable than solid one. Easy ways to protect armature do not work as with solid concrete. Zinc anodized steel or other consumable protections will simply be consumed much earlier than in solid concrete, or worse, be eaten by lower PH of a foam concrete after settling. You have to put additional alkalinisers, or flyash, but they can destroy the foam. Finding a foam that will stand your alkaliniser, or a particular composition of flyash (flyash from different powerplants and blast furnaces can be dramatically different chemically and change in composition over time!) is always a challenge.
2. Faster hardening, especially with alkalinisers or geopolymer base - 40 MPa in just 2 days. You also have to spray formwork with water copiously to prevent it from premature drying.
3. Bigger sensitivity to chemical purity of components in general. Additives for foam concrete are an esoteric matter.
What I say about it: advantages worth the trouble
1. You can go down in density down to 350 per cube, or even 150 if you are a concrete chemistry magician. 350 gives you 0.1 W/mK thermal conductivity
2. Incomparably more flowable and pumpable.
3. You can use cements that are wholly geopolymer based or natural cements which is a huge economic incentive.
4. Can be used structurally above 600 per cube density with 13kg/cm2 load bearing capacity. Load bearing capacity goes up non-linearly. 850/cube already give you 30kg/cm2
5. Settled foam concrete is workable with just saws and hand tools. If you have to fix a screw up, it is much easier than with solid Portland cement.
6. Works like magic with stay-in-place formwork.
Only the very top end of multifamily rental housing is comparable in quality to ordinary single family homes. I have found high-rises to be more solid than mid-rises, probably because steel is a must.
You have to look at just how deeply our culture rejected cities and how deeply ingrained the American Dream of suburbia became.
Buying extra insulation, or a "smart thermostat" or any other "energy saving" thingamajig would cost a lot more than the payoff would ever be.
I don't know how much it costs to heat my place, since I only have storage heaters, so it all gets merged in with the rest of my electricity usage.
Your insulation could definitely be improved - I live in Scotland and when it's 0C inside it seems to equalise at about 10C simply from having humans in with cooking and lighting. That's still a bit uncomfortably cold so I run the heating, but without good insulation a lot of paid for heat would be escaping.
The only time I've actually noticed it being brutally cold was coming home after several weeks abroad, where I'd turned the heaters off before I left to save power. Coming home after that was particularly unpleasant.
Additionally, I'm on the ground floor on a street corner, so three walls exposed to the air and one wall shared with a large garage —— which i assume isn't heated.
14° C (just under 60° F for us yanks) is tolerable with sweats and movement, or even just direct sunlight, but you're living in a pretty temperate place if you can keep it there with an uninsulated building. Vancouver is not such a temperate place.
The lack of dollar signs on the thermostat leads many others to heat above, sometimes well above, 20 °C in winter.
It's called cavity wall insulation. I don't know if the method could be applied to a wooden house.
Kris de Decker has written extensively on this topic: why convection heating is problematic, which alternatives exist, and the problems with focusing exclusively on energy efficiency[0][1][2][3]. In short:
- On a meta-level, the actual problem we are trying to solve is not one of heating. Heating is a solution. The problem we are solving is how to stay warm. Framing it this way opens up entirely new options to explore.
- Air is a natural insulator with low thermal capacity, so an incredibly inefficient transport medium of heat. When heating up a cold room, the ambient air may heat up quickly, but the objects in a room can stay cold for very long.
- Convection heating requires that the heated air does not escape the room, so we end up with a trade-off between heating and fresh air. Personal anecdote related to this: I live in house that is so well-insulated that I cannot sleep with the window closed, feeling exhausted and out of breath in the morning (likely more due to the rise of CO2 than a lack of oxygen, but the result is the same). These days I sleep with the window open, under three layers of blankets, and the heating to a bare minimum.
- Convection heating also heats up the entire space, which is really wasteful: we really only care about heating the humans and other living things inside this space. To point out how ridiculous this really is: hot air naturally rises to the ceiling first, where nobody needs it. (admittedly, when a space remains damp and cold for a very long period of time, there is the problem of mould to consider. There are solutions for that, and they are more sustainable than wasting heat with convection heating)
- Because the heat in the air is absorbed at the windows, we have to put the convection heater next to it to get an even heat gradient in the room. So in other words: we put our heat source right next to the biggest heat-sink in the room.
Other methods of staying warm, like radiant heating or electrically heated clothing (yes, this exists) can bypass most if not all of these issues.
The problem is that we are trying to make modern lifestyle more efficient without radically questioning the lifestyle itself.
Elizabeth Shove had a good paper on this problem, although it can get quite dense[4]. Kris de Decker has a more accessible summary of it[3]. I'll highlight some stuff from Shove's paper:
> Programmes of energy efficiency are politically uncontroversial precisely because they take current interpretations of ‘service’ for granted. But in normalizing specific definitions of service, methods of evaluating efficiency carry normative assumptions about ‘need’ forward, invisibly bedding them into future programmes of research and development.
> In conclusion, the un-reflexive pursuit of energy efficiency is problematic not because it does not work, or because the benefits are absorbed elsewhere, as the rebound argument suggests, but because it does work– via the necessary concept of equivalence of service – to sustain, perhaps escalate but never undermine [...] increasingly energy-intensive ways of life.
> In response, it is tempting to call for greater interdisciplinarity, and new ideas are definitely needed. However, as Daniels and Rose perceptively observed, it is no accident that the field of energy efficiency is ‘devoid of any vision of history’ (Daniels & Rose, 1982) This is not something that can be fixed since it is an unavoidable consequence of how programmes of efficiency are conceptualized. In the end, it is impossible to imagine how organizations like the IEA, the EU or the UK Committee on Climate Change might come to recognize and explicitly evaluate their own role in making and shaping present and future ‘needs’. At the same time, and as historians might well point out, the ambition of reproducing ‘present’ standards of living, now and in the years ahead, is doomed to fail.
Better energy efficiency is important, but only one path. And on it's own, it will be as effective as insisting on building smaller vacuum tubes.
[0] http://www.lowtechmagazine.com/2015/03/radiant-and-conductiv...
[1] http://www.lowtechmagazine.com/2015/03/local-heating.html
[2] http://www.lowtechmagazine.com/2013/11/heat-your-clothes-not...
[3] http://www.tandfonline.com/doi/full/10.1080/09613218.2017.13...
[4] http://www.lowtechmagazine.com/2018/01/bedazzled-by-energy-e...
What on earth makes you think that? It's incorrect.
Look, I don't know the Passive Housing standard, I'm inferring based on the information given in the video and article. If I'm wrong, don't just say "this is incorrect", tell me what the standard actually is.
That's exactly wrong for the case of a passive house where the goal is usually to do the heating cooling entirely with the ventilation air.
In other cities, not so much. You have to resort to fossil fuel heating anywhere where temperature get below -20 for extended time.
If the temperature simply goes to -20 and stays there 24/7 for the rest of the seasons. You have to design a house differently.
I'm not sure about Alps region. Are conditions there like that?
I skipped on renting in a passive building in Bellevue I saw this summer because I couldn’t open the windows (well, there was one slip I could open just a little bit). It was a nice apartment at a decent discount as well.
https://www.rethinktokyo.com/2018/02/07/man-most-energy-effi...