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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)

#111

Post by KaiserPro »

ricardo81 wrote: post #103

I'm in the UK which has one of the oldest/energy inefficient housing stocks in Europe. After buying a house built in 1890 I've been made more aware how poor they can be. After replacing the old secondary glazed windows and replacing the old inefficient gas boiler, I'm moving onto replacing the front and back door, and insulating the suspended floor, walls and room in roof. The walls are solid whinstone about 600mm th…

The next most effective thing to do is External wall insulation. However that'll mean that you'll loose the whinstone look. (unless you pay a _lot_ to get whinstone like shims put on after)

The alternative is to have internal wall insulation: https://www.insulationsuperstore.co.uk/product/vacutherm-vac...

This is as effective as ~150mm of rockwool, but only 20mm thick. So this can be stuck behind plaster/plasterboard.

but its not easy to work with, or widespread yet.

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

#112

Post by masklinn »

KaiserPro wrote: post #107

TLDR: point one: you need insulation _everywhere_, along with some thermal mass to make sure there is some inertia to keep temperature even. This means that putting a jacket around the outside of a brick/cement structure is generally better than putting it inside. You need to insulate under the floor. External wall insulation is not overly expensive. Its about 50% more expensive than a standard silicon render (in the…

> Windows and doors are normally the weak spot. Standard double glazing has a U value of about 2. Depending on the coating and the position, they can also let in up to 2kw/m2 of heat through solar gain.

Also do be careful of thermal bridges and missing seals at and around the frame.

My current rental is relatively well insulated all in all, but one of the huge weakpoints is the stone sill of one of the east-facing windows, I don’t know what the builders fucked up but in winter it can literally serve as a fridge.

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

#113

Post by Sankozi »

jaclaz wrote: post #92
poseva wrote: post #75

Earlier quoted context omitted.

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…

That depends on how deep you dig, but of course going deep enough has a cost that may be far greater than the kind of insulation you used. The 20-25% of increase in cost is a good proxi (from my personal experience I would have said 25-30%), but, from an economical standpoint it should be compared with savings over time (in the same region). To give you an example in Italy, last time I calculated it, this 25-30% incr…

5% return per year (or more in case of price changes or regulations forcing you to change heating source) does not seem that "philosophical".

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

#114

Post by KaiserPro »

poseva wrote: post #47
locallost wrote: post #7

I watched a report on a block of "passive houses" in Germany and the people liked it, but had a complaint that the air is too dry, so they dried their laundry indoors. I'm a fan of the idea, so not really critical, but I wonder what it's really like to live in one.

Instead of a heat recovery ventilation you can use energy recovery ventilation which gets back some of the humidity, otherwise just buy a cheap electric boiling humidifier and it you get the job done. What is important that in the coldest part of the winter you can turn down the ventilation to a minimal, something like 0.3 hourly exchanges per hour.

> winter you can turn down the ventilation to a minimal

The problem is that the Heat exchanger actively draws moisture out, as it has a huge cold surface area that forces water out of the air. If you don't change the air it feels stuffy.

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

#115

Post by dx034 »

mattlondon wrote: post #33

I wonder how these "no heating"/"no cooling" homes work in situations like mine: my wife is permanently freezing cold, sitting around inside with multiple layers on, sometimes a blanket, and the heating on full-blast while I am walking around in shorts and t-shirt sweating? I.e. people have different ideas about what a comfortable temperature is. In my wife's example it seems like unless she can actually "feel the he…

From experience I can say that it works. Simply by using different clothes (as you described, t-shirt vs multiple layers). The only people who really struggle with no heating homes are those who need colder temperatures to sleep. I had several guests who complained that they'd like it cooler at night than during the day. However, that's not really possible if the house isn't really heated anyway and thus won't lose heat during the night.

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

#116

Post by londons_explore »

I think a key issue is that generally the person designing a house isn't the same person who will be paying the energy bills in 30 years time.

Few people will pay a lot extra for a better insulated house.

The end result is that the cheapest insulation allowed by law is used rather than something that costs more today but saves a lot in the long run.

I wonder if a solution to this problem might take the form of "We'll sell you the house, and promise to pay half the energy bill for the next 50 years". Obviously there are issues with that... is there a better way to align incentives?

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

#117

Post by sgt »

South Africa here, it's not common to build energy efficient houses although it's gradually getting slightly better.

I'm busy changing all my windows to double glazed (single glazed is the norm, believe it or not) and proper insulation in above the ceiling.

Instead of freezing my ass off every winter it's now super pleasant, and it's cooler in summer. Such a non-brainer - I just don't understand why people don't do this more.

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

#118

Post by dx034 »

bawolff wrote: post #60

I'm kind of curious what weather range they are talking about. As someone from Canada, i somehow don't think this would work over here in the -40 winter.

I lived in a PassivHouse in Germany. Didn't need to heat if it was more than 4C outside (less if more people were at home). I never experienced -40C, but at -20C it worked fine. Probably the only time all heating had to run to some degree 24/7. I'm sure that -40C would've been fine as well.

In the end it all doesn't matter. You build the house to some standard and then design the heating system to be able to cover thermal loss for the expected temperature range. In Canada you'd probably just add twice as much heating as you would in most of Europe. But especially at those temperatures, very well insulated homes will save a ton of money.

The only part that kind of worked less well at very low temperatures was the heat exchanger for the ventilation system. It didn't run at full capacity if it was well below freezing. But I guess there are other systems out there which are designed for -40C as well.

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

#119

Post by ricardo81 »

KaiserPro wrote: post #111
ricardo81 wrote: post #103

I'm in the UK which has one of the oldest/energy inefficient housing stocks in Europe. After buying a house built in 1890 I've been made more aware how poor they can be. After replacing the old secondary glazed windows and replacing the old inefficient gas boiler, I'm moving onto replacing the front and back door, and insulating the suspended floor, walls and room in roof. The walls are solid whinstone about 600mm th…

The next most effective thing to do is External wall insulation. However that'll mean that you'll loose the whinstone look. (unless you pay a _lot_ to get whinstone like shims put on after) The alternative is to have internal wall insulation: https://www.insulationsuperstore.co.uk/product/vacutherm-vac... This is as effective as ~150mm of rockwool, but only 20mm thick. So this can be stuck behind plaster/plasterboard…

Yes, it's one of the top recommendations (internal wall insulation) on my EPC and have had a survey. 60mm PIR boards would be used. Turns out I wouldn't have to sacrifice much space but would have to pay a bit extra replacing the cornices.

There are some regional grants in the UK that can cover a large portion of the amount. For me, it is £7.5K, with the quote I received at £9K. This would not have covered the kitchen or bathroom.

Going by EPC recommendations and numbers alone, I can reduce my energy requirement by about 40%.

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

#120

Post by dx034 »

perceptronas wrote: post #94
mdp2021 wrote: post #82

Earlier quoted context omitted.

> with good ventilation Mandate windows?! > heat pumps That means (if I understand you correctly), fans. That is noise pollution - some will not have it, and some will not bear it. And (after experience), heat pumps can be inadequate for heating: they can raise a temperature, not warm the environment.

Windows> Heat exchangers can be up to 90% effective at saving heat, while window ventilation will be 0%. Noise pollution> In my cold climate, whoever goes with heat pumps - they usually go with "air-water" systems. Meaning only outside you have fans and inside you have your typical floor heating.

Much higher than 90%. The one I had in the passive house I lived in was specified to 98% at most temperature ranges. I guess most of the time the temperature difference isn't that large anyway (<20C) so they will lose next to no heat.
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