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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)

#161

Post by jakub_g »

ricardobayes wrote: post #142
joking wrote: post #89

Earlier quoted context omitted.

no harsh climate overall so much less insulation is needed?

Mainland Spain falls into the single digits at night at winter so definitely would need insulation, because there is also no central heating. People resort to heating with their aircons and portable heaters. I'm sad because I expected better infrastructure from 45% income tax at the highest bracket.

I come from Poland (sub-zero in winter; can be anywhere from -20C to +10C but typically 0-5C), but the winter I lived on the Spanish eastern coast was the coldest in my life: thin walls and windows, stone floor, no heating apart from little portable heaters, 5 degrees and rain outside.

Now I live in French southern coast, the buildings are slightly better but still poor. In my place even with all heaters I have on max, I'm nowhere near as comfortable as in properly built and heated apartments in my home place (actually when visiting friends in Poland in winter I'm almost overheating!).

Basically half of the year it's quite uncomfortable to stay at home for prolonged time: for ~4 months a year at winter; then again for ~2-3 months at summer (+26C at home with blinds down unless you put aircon on max for hours). Kinda suboptimal for WFH to be honest :)

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

#162

Post by KaiserPro »

bainsfather wrote: post #136
KaiserPro wrote: post #111

Earlier quoted context omitted.

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…

I followed your link, but am confused and/or doubtful: how do you replace 150mm of rockwool with 20mm of anything other than a good vacuum? It says that they are 'very low internal pressure' - but if it contains any kind of gas (which i presume it must do - air if nothing else) then the conductivity does not depend on pressure until the mean-free-path has increased to be > the width of the container. Is this product…

From what I've seen, its basically a honeycomb with a thick plastic coated foil to act as an atmospheric barrier. I came across it from a number of sites, but I've not managed to get any samples yet.

> And how do you maintain the 'very low internal pressure' over the decades that you will need it for?

now thats a million dollar question. I don't know.

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

#163

Post by alkonaut »

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…

> Standard double glazing

How is the code still allowing new construction with windows having U of 2 (such as double glazing)? A more restrictive code would reduce a country's CO2 footprint, companies would sell more expensive products like windows, and no one except the few constructing new homes would be economically impacted - and obviously only short term, while the economic gains are reaped by everyone. So how is this not politically easy to just...do?

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

#164

Post by ricardo81 »

rogalian wrote: post #156
ricardo81 wrote: post #119

Earlier quoted context omitted.

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 kitche…

Had to sign up for this. Take extra care to use appropriate materials for a house this age or you'll create more problems than you solve. Solid stone walls need to breathe! Make sure you've spoken with a surveyor specialising in heritage property too. PIR boards are almost certainly unsuitable. https://www.victorian-house.co.uk/ (be sure to pick up a copy of the Haynes Victorian House manual, it's a gem) https://www.…

Thanks for taking the time to sign up.

I intend to use rockwool for the floor and roof crawl space.

Luckily I have a relative in the field who can share advice. I am conscientious of the condensation issue. There's a company local to me who use hemp boards which are porous. What you say is definitely something to consider given the extent of work involved, and to possibly undo.

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

#165

Post by KaiserPro »

lbriner wrote: post #129
KaiserPro wrote: post #111

Earlier quoted context omitted.

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…

An easier solution is plasterboard already bonded to PIR or XPS. The XPS is cheaper and I don't think it will make a massive difference depending on all the other challenges like windows and doors. You can simply stick this to existing walls with adhesive foam and then dry-line or skim the boards afterwards. To do it well, though, you will often need to cut out/remove any laminate flooring so the boards can meet the…

> plasterboard already bonded to PIR

As you point out they are normally ~25mm or so of EPS/XPS. which doesn't do _much_, especially compared to 600mm of stone. Plus XPS is pretty flammable, so with electricity cables sandwiched between it, its not a great thing to have inside the house.

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

#166

Post by empiricus »

mdp2021 wrote: post #121
elric wrote: post #105

Earlier quoted context omitted.

You're wrong on both counts. Windows don't make for very good ventilation. They are prone to letting in either too much or too little air, which means you're either wasting a lot of heat, or are not getting enough fresh air. Mechanical ventilation with energy recovery is far superior. Windows, of course, are great for letting in natural light and for creating a sense of spaciousness etc. Heat pumps don't always need…

> Windows don't make for very good ventilation The point was not with ventilation quality, but with the feasibility and compromises of alternatives. (The strict point was with defining "mandating good ventilation".) Mechanical ventilation with energy recovery may be far superior, but if that means constant noise it will be an issue - to some, a radical issue. > They definitely can warm an entire house And I have stat…

"Mechanical ventilation with energy recovery may be far superior, but if that means constant noise it will be an issue - to some, a radical issue." I've installed this in my house, it is virtually silent. This is for ~200m3 of clean air/hour. If I turn it on higher you can hear it a little.

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

#167

Post by markvdb »

ricardo81 wrote: post #119
KaiserPro wrote: post #111

Earlier quoted context omitted.

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 kitche…

Be super careful internally insulating an old house. This can cause _a lot_ of humidity problems if not done _exactly_ right. Very often, there is no way to do it exactly right!

I would recommend you to consider breathable internal insulation materials, combined with breathable finish layers of course! Some hints.

Roof (or attic floor) insulation is the most important. I imagine those have been done properly already.

Walls. There's industrial products for walls, like Xella Multipor. You may also want to have a look at eco products, especially if working on the place yourself. Hempcrete is a fairly forgiving material that works rather well for this purpose. Rather expensive to have it installed, but easy to do yourself.

Ground floors. Have a look at foam glass [0] insulation. It both stabilises and insulates, is moisture and fire proof, not horribly expensive and saves you from having to put in a layer of concrete. Not super well known yet, but growing in popularity. A wonderful material and super easy and forgiving to work with. A no-brainer really in many cases...

[0] https://en.wikipedia.org/wiki/Foam_glass

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

#169

Post by KaiserPro »

alkonaut wrote: post #163
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…

> Standard double glazing How is the code still allowing new construction with windows having U of 2 (such as double glazing)? A more restrictive code would reduce a country's CO2 footprint, companies would sell more expensive products like windows, and no one except the few constructing new homes would be economically impacted - and obviously only short term, while the economic gains are reaped by everyone. So how i…

> How is the code still allowing new construction with windows having U of 2 (such as double glazing)

its complex. but as I'm retrofitting the rules are different. The standards are here: https://great-home.co.uk/building-regulations-current-u-valu...

But the real kicker is that glazing should have bleeder vents in them, in some circumstances. Which is a pain in the arse. Most of my windows don't have them, but the two in the loft extension do.

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

#170

Post by alkonaut »

KaiserPro wrote: post #169
alkonaut wrote: post #163

Earlier quoted context omitted.

> Standard double glazing How is the code still allowing new construction with windows having U of 2 (such as double glazing)? A more restrictive code would reduce a country's CO2 footprint, companies would sell more expensive products like windows, and no one except the few constructing new homes would be economically impacted - and obviously only short term, while the economic gains are reaped by everyone. So how i…

> How is the code still allowing new construction with windows having U of 2 (such as double glazing) its complex. but as I'm retrofitting the rules are different. The standards are here: https://great-home.co.uk/building-regulations-current-u-valu... But the real kicker is that glazing should have bleeder vents in them, in some circumstances. Which is a pain in the arse. Most of my windows don't have them, but the t…

Yeah having different rules for retrofitting is understandable (Although it would be good if those who retrofit were at least required to improve the status quo of the building, if not required to bring up to the standard of new building).

But what blocks the code from saying e.g. U=1.2 for new construction which is a normal (and honestly pretty cheap) triple glass window?

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