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How to build homes with virtually no heating (2020)

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Re: How to build homes with virtually no heating (2020)

#201

Post by lotsofpulp »

Cthulhu_ wrote: post #62
Mromson wrote: post #11

It saddens me that construction quality is almost irrelevant when building a new building nowadays. The profit difference between a well-isolated passive building and one that merely meets the minimal standards, is often very small, so why bother building a passive building? My personal interest in passive buildings generally revolve around maintenance. Passive houses seem to require far less maintenance.

> It saddens me that construction quality is almost irrelevant when building a new building nowadays. Depends on where you live; houses in the Netherlands are built to high standards when it comes to things like insulation, build quality, electrification, etc. Are houses in the US still built with 2x4's and drywall? You'd think they would move to what we have here in the Netherlands, mostly sturdy concrete blocks, in…

> I mean the amount of clips I see on the youtubes of people breaking walls make me cringe. A wall should break you, not the other way around, :D

Why? I think calculating heat loss, noise levels, wireless signals, fire resistance, ecological cost, etc would be decent metrics to judge the merits of a wall.

But if you are living in civilization, I do not see why the wall withstanding the impact of a body is something I should care about. Also, there is almost always an external envelope of exterior siding plus plywood sheathing that I have never seen penetrated by an individual without tools.

Re: How to build homes with virtually no heating (2020)

#202

Post by poseva »

goodpoint wrote: post #198
poseva wrote: post #43

I've also built a simple and small (99sqm) PassivHaus in Romania, 5 years ago. Everybody, and I mean everybody from family to friends called me nuts, but I've got my payback this winter when the energy prices went trough the roof and I'm just slightly affected. The house is elevated from the ground on 12 concrete columns so that I can insulate under the foundation beams using glass foam, insulation on walls is 30 cm…

> small (99sqm) Is that correct? 99 is not small at all.

Small in comparison with a typical single family homes that goes >150 sqm in my area. I completely agree with you, 99 sqm is more than enough for a 4 people family.

Re: How to build homes with virtually no heating (2020)

#203

Post by tejohnso »

poseva wrote: post #75
kitd wrote: post #64

Earlier quoted context omitted.

It is interesting that you insulate under the house. One of the more intriguing passive house designs I saw was one where the insulation went down 2-3m into the ground all around the house footprint. This trapped the natural ground heat within that area and fed it upwards into the house. It took about 18 months for the ground to warm up, but once it was there, the ground/house warmed itself with virtually no input. T…

Really interesting. I've read about also "foundation insulation skirt" that allows you to create a warmer earth mass under the house. To be honest this was the biggest "complaint" that others had in regards of how a built the house, the general knowledge says that the earth is warm and you don't need to insulate against it... but the earth is maybe 5-10 degree, of course warmer than outside -5..-10 but still a lot co…

Insulation under the home, and skirted around it. You may be thinking of a Frost Protected Shallow Foundation[1]. A nice alternative to excavating in order to get below the frost line. I dream of doing this as part of a self built small passive house project.

[1]: https://www.greenbuildingsolutions.org/blog/frost-protected-...

Re: How to build homes with virtually no heating (2020)

#204

Post by WkndTriathlete »

naikrovek wrote: post #176

In 1989 my grandparents built a home with 12" thick walls (6" was normal at the time, in the area) and carefully vapor-sealed the entire house, taking extra special care to avoid holes which would let air move through the house in an unplanned way. They paid extra (a lot extra) for the highest insulation value available for the fiberglass rolls they installed in the outside walls. They double-stacked the insulation,…

> In 1989 my grandparents built a home ... and carefully vapor-sealed the entire house

In the upper Midwest there were a number of homes built this way in the 80s/90s. 10-15 years later they all had black mold (nasty health hazard) growing in the walls because moisture couldn't escape from the house. All homes are now required to have air-to-air heat exchangers for this reason.

Re: How to build homes with virtually no heating (2020)

#205

Post by markvdb »

lelanthran wrote: post #179
markvdb wrote: post #146

Earlier quoted context omitted.

> It is interesting that you insulate under the house. Near our place in the countryside, required foundation depth is 1.4m to protect from frost heave. Use an insulated slab and that requirement goes away. The insulation keeps the heat in the ground. It protects the ground under the house from freezing. Nobody cares about regulations here, but they do about getting proper foundations...

> The insulation keeps the heat in the ground. It protects the ground under the house from freezing. If it is preventing the ground under the house from freezing, then it is supplying heat to that ground. That's a energy-negative process - some of the heat you generate is used to maintain the warmth of the ground.

Au contraire, my dear Watson.

Without under-slab insulation, the heat emanating from the ground below the house escapes very quickly. This heat we don't generate. It occurs naturally. This is about using the naturally escaping heat to keep the ground under the house from freezing, about raising the frost depth.

This technique is especially interesting for holiday homes not permanently heated in northern climates. It's fairly standard in Scandinavia, up and coming in the Baltics, but less known in the US.

In the US, it's usually called FPFS or frost protected shallow foundations. [0]

[0] https://www.ncei.noaa.gov/products/land-based-station/frost-...

Re: How to build homes with virtually no heating (2020)

#206

Post by jaclaz »

maxerickson wrote: post #180
jaclaz wrote: post #141

Earlier quoted context omitted.

I don't understand fully your way of reasoning. A normal house costs - say - 200,000 "units" (dollars, euro, whatever). Making it "energy saving" costs an additional 60,000 units. In 20 years time you will be spending 60,000 units (3,000 per year) less for energy costs (and here we are assuming that ventilation and heating/cooling machines in the "better" house have the same maintenance costs than the ones in "normal…

If you step back a bit, it makes sense for society to push for the construction techniques that minimize the lifetime cost of the building. Here, buildings typically last for much longer than 20 years. And then there's the whole thing where energy costs may not be fully priced into the use.

Sure, but then that is a "political" decision at government level, not your "free" choice.

It is clear that the (good) trend is towards mandating "better" insulation (and thus less energy consumption) but it is not like a government can say "ok, starting tomorrow all new houses must be passive", as that translates to "ok, starting from tomorrow price of all new houses will increase by 30%".

They are introducing - little by little - minimal requirements, and introducing in parallel some (BTW badly implemented at least here in Italy) economic incentives to better existing houses but it will take many years before they can impose "only passive" houses, and in any case, "new houses" are such a trifling percentage of existing buildings that they won't make a dent in the overall energy consumption, it is much more effective, given the amount to slightly better the much larger amount of existing buildings.

Also it is not as easy as it seems, for the last 10-20 years a number of houses have been built in the (at the time) energy classes A-B-C without mechanical ventilation/heat exchangers, with - let's call them "not fully tested" - construction methods and now that they are aging they show the problems emerging (humidity/mould, maintenance of windows, decay of insulation packets/facades, etc.), as often happens with new technologies.

Re: How to build homes with virtually no heating (2020)

#207

Post by poseva »

throw0101a wrote: post #186
poseva wrote: post #43

I've also built a simple and small (99sqm) PassivHaus in Romania, 5 years ago. Everybody, and I mean everybody from family to friends called me nuts, but I've got my payback this winter when the energy prices went trough the roof and I'm just slightly affected. The house is elevated from the ground on 12 concrete columns so that I can insulate under the foundation beams using glass foam, insulation on walls is 30 cm…

> What is the big difference between houses built in North America and Europe is that the European houses are built using concrete and masonry which give them a lot of thermal mass which is crucial to this kind of builds. Here's a 500 sq. m. (5000 sq. ft.) house built with heating equipment that uses 1800W (the equivalent of a hair drier): * https://www.youtube.com/watch?v=_vul4vMFdkA The same person building his own…

I agree, you do not need concrete and brick but you also need to take into account the local traditions. For ex. building a wood house (framing or CLT) would have cost much more than concrete and bricks and was also much more prone to errors because of the builders lack of experience, at least in my area and country.

Recently in Romania it really took of building houses using CLT (cross-laminated-timber) but it costs so much more than a regular brick and mortar house that few people afford it.

When -15 outside and 20 degrees inside, my house requires 2000W to keep the balance. This kind of simulations are done using PHPP package from PassivHaus Institut.

L.E. What I wanted to point out, thermal mass can have a huge impact on the house energy footprint.. to give you an example, today and tomorrow will be sunny days and this will drive my interior temp to about 23-24 degrees, this heat will heat-up the masonry and slabs and then give me back the heat in the next days when there will be no sun.

Re: How to build homes with virtually no heating (2020)

#208

Post by bluGill »

throw0101a wrote: post #186
poseva wrote: post #43

I've also built a simple and small (99sqm) PassivHaus in Romania, 5 years ago. Everybody, and I mean everybody from family to friends called me nuts, but I've got my payback this winter when the energy prices went trough the roof and I'm just slightly affected. The house is elevated from the ground on 12 concrete columns so that I can insulate under the foundation beams using glass foam, insulation on walls is 30 cm…

> What is the big difference between houses built in North America and Europe is that the European houses are built using concrete and masonry which give them a lot of thermal mass which is crucial to this kind of builds. Here's a 500 sq. m. (5000 sq. ft.) house built with heating equipment that uses 1800W (the equivalent of a hair drier): * https://www.youtube.com/watch?v=_vul4vMFdkA The same person building his own…

Modern codes have moved back to 2x4, then they put continuous foam on the outside of that to make the total the width of a.2x6 wall. Wood is not a great insulator and you have to have some

Re: How to build homes with virtually no heating (2020)

#209

Post by jaclaz »

empiricus wrote: post #158
jaclaz wrote: post #141

Earlier quoted context omitted.

I don't understand fully your way of reasoning. A normal house costs - say - 200,000 "units" (dollars, euro, whatever). Making it "energy saving" costs an additional 60,000 units. In 20 years time you will be spending 60,000 units (3,000 per year) less for energy costs (and here we are assuming that ventilation and heating/cooling machines in the "better" house have the same maintenance costs than the ones in "normal…

Not only "philosophical", better insulated houses are also more comfortable.

Sure, but not all houses are built for "you" to live in perpetually.

You build a house according to the minimal requirements of your local codes/norms.

If you next year go to another city you may either sell the house or rent it (at average market value).

You build a "passive house".

If you next year go to another city you may either sell the house or rent it.

Do you believe you can easily get 30% more rent or sale price because it is passive?

Re: How to build homes with virtually no heating (2020)

#210

Post by Mvandenbergh »

throw0101a wrote: post #186
poseva wrote: post #43

I've also built a simple and small (99sqm) PassivHaus in Romania, 5 years ago. Everybody, and I mean everybody from family to friends called me nuts, but I've got my payback this winter when the energy prices went trough the roof and I'm just slightly affected. The house is elevated from the ground on 12 concrete columns so that I can insulate under the foundation beams using glass foam, insulation on walls is 30 cm…

> What is the big difference between houses built in North America and Europe is that the European houses are built using concrete and masonry which give them a lot of thermal mass which is crucial to this kind of builds. Here's a 500 sq. m. (5000 sq. ft.) house built with heating equipment that uses 1800W (the equivalent of a hair drier): * https://www.youtube.com/watch?v=_vul4vMFdkA The same person building his own…

Moving insulation outside the frame also helps reduce the effect of thermal bridging although with timber that's not so important as it is with steel.
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