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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)

#211

Post by goodpoint »

Terry_Roll wrote: post #4

Its all very well using environmental energy sources to heat and cool a building, but very little attention is given over to clearing the air. Besides the pollutants from cleaning products and product breakdown, CO2 levels inside a building can have a stimulating effect on the body, which kind of destroys the purpose of a relaxation of a home.

> CO2 levels inside a building can have a stimulating effect on the body, which kind of destroys the purpose of a relaxation of a home

Citation really needed.

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

#212

Post by poseva »

Mromson wrote: post #91
poseva wrote: post #46

Earlier quoted context omitted.

First of all, if you build a PassivHaus in normal climate (not cold) you will be amazed to see that you do not need a heat pump, you can just use normal electric boiler for hot water and use electric underfloor heating mats for heating, or infrared panels mounted on the roof. On the other side, air-to-air heat pumps have gotten cheaper by the year, you can buy a decent heat pump (NIBE) with about 4500-5000 euros.

Electric boilers are extremely energy inefficient compared with heat pumps. If you built a Passive House, not going the extra mile for a heat pump seems silly to me. Not to mention that heat pumps can easily protect you against heatwaves (should any happen).

Exactly what coryrc said in his comment, for a PassivHaus you recover very slowly the cost of the heatpump and if it brakes once in 10-15 years while it takes to recover the investition... you will never recover it.

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

#213

Post by Mvandenbergh »

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…

I work on energy systems modelling and how domestic thermal performance interfaces with that - the UK has not just "one of the oldest in Europe" it actually has the oldest in the world. Many European countries had a lot more post WWII construction so at least have cavity walls (even if in many cases not filled until later).

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

#214

Post by Gravityloss »

arethuza wrote: post #131
Gravityloss wrote: post #125

Earlier quoted context omitted.

How would that work? Average temperature in the UK is about 15 C. If your house is at 24 C, this would mean you are constantly leaking heat into the ground from the bottom... I guess one can consider the cube of earth an insulator, it's got a lousy insulation value per meter but it makes it up in thickness.

Don't think 15C is correct - looks more like 8.5C to 11C in England and 7C to 9C in Scotland. http://projectbritain.com/weather/average.htm

Sorry, I was wrong indeed, thanks for the correction

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

#215

Post by Moru »

2rsf wrote: post #199
Moru wrote: post #56

Earlier quoted context omitted.

First one was built 20 years ago but getting more popular after 2010. You can order them, it's a building standard so does not require anything from you except money. But they say it's not that much more expensive than a normal swedish house since we already have a lot of isolation and 3 glass windows as standard for the climate.

So what is the difference and why does my modern Swedish house, with heat recovery ventilation and east-south facing windows consumes more energy to heat?

More than what?

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

#216

Post by Markoff »

newaccount74 wrote: post #52
jsiaajdsdaa wrote: post #39

Earlier quoted context omitted.

Sounds like one of you might have a health condition. She could be underweight or anemic, you could be overweight or etc.

I'm pretty sure that totally healthy people also prefer different temperatures. And it's common that women prefer it slightly warmer; men do have a slightly higher metabolic rate on average even when they have the same height/weight, and those extra calories that the body uses end up as heat.

It's common, but I find it strange considering women have overal much more fat, so you would expect the roles will be reversed.

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

#217

Post by poseva »

I want to also to highlight the importance of the building airtightness (Air Changes per Hour) on the energy consumption needed for heating.

I saw an example at some point in one of PassivHaus presentation and it was like this:

0.3 ACH -> 1.74 kWh/m2year (for a 100 sqm house means, 174 kwh per year for heating)

0.6 ACH -> 3.49 kWh/m2year (PassivHaus limit)

1.0 ACH -> 5.81 kWh/m2year

1.5 ACH -> 8.72 kWh/m2year (Low energy house limit)

4.5 ACH -> 26.5 kWh/m2*year (typical house)

This is for the same house with the same insulation. Of course you cannot achieve this kind of airtightness without careful planning and using a lot of self-adhesive tape (SIGA, ROTHOBLASS and other manufactures that can guarantee its effectiveness up to 50 years)

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

#218

Post by wcoenen »

bee_rider wrote: post #83
wcoenen wrote: post #61

Earlier quoted context omitted.

It's the opposite for us; I'm the one feeling cold, while my wife is comfortable. I started wearing a layer of thermal underwear in the cold seasons to compensate.

You must embrace the cold. Any attempt to warm yourself will just make your body expect warmth. Never turn on the heat, and you'll slowly adapt along with the seasons. Maybe set the thermostat to 33F so that the pipes don't freeze...

The human body doesn't "expect" anything, it simply must maintain its core temperature. If the temperature of the environment goes lower, the body responds by

1) increasing thermogenesis, i.e. convert chemical energy to heat through metabolism

2) reducing heat loss through the extremities by reducing blood flow there. In other words, you get cold feet and hands etc.

For people not bothered by cold, presumably it's mostly (1). For me, being skinny and not having a big appetite, it seems to be mostly (2). I suppose I could get used to having cold extremities half the year. But why suffer if I can simply put on an extra layer of clothing? I don't see the point.

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

#219

Post by em-bee »

poseva wrote: post #202
goodpoint wrote: post #198

Earlier quoted context omitted.

> 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.

it depends on how you can use the space. 4 people can mean three bedrooms. in some parts of asia the average 3-bedroom flat is 150m². a few years ago i did a search in a european city and likewise was unable to find 3-bedroom apartments with less than 120m². 4 was 150m² minimum.

the problem is huge living rooms that can't be divided up and repurposed to make living space for more people.

work from home doesn't need a lot of space, but with young kids i absolutely need a lockable room. my current office room is 5m². plenty of space. but finding an apartment with that kind of room is rare.

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

#220

Post by mnw21cam »

markvdb wrote: post #167
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…

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.…

The one key rule that you should always follow is to have your water-impermeable layer on the warm side of the insulation.

So, I'd recommend against breathable internal insulation, because that will make your solid wall (water-impermeable layer) colder, but still exposed to the humid inside air, and this could cause condensation on that cold wall. As an example of this, I have rubbish double glazing, and when the temperature drops outside, if I have just the curtains drawn (which don't really provide any insulation) then I'm fine, but if I lower the thermal blackout blinds, then I get loads of condensation on the inside of the windows, which I remove with a window vac in the morning.

Breathable external insulation is less of a problem, because it warms up the wall, while exposing it to the comparatively dry air from outside, so you shouldn't get any condensation.

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