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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)

#271

Post by hourislate »

turtlebits wrote: post #269
hourislate wrote: post #263

I've been touting the benefits of Spray Foam Insulation for years. It is actually incredible how much money you can save on HVAC every year. Your Heating and Cooling equipment can be halved in size and your living space is draft free and incredibly comfortable. Mate this with geothermal and your utility bills to heat and cool are equivalent to someones Starbucks habit (maybe less). If the North American building code…

Spray foam is very expensive and is not sustainable. Mineral wool/rockwool is also fairly popular but pricey as well. Also, it's not just adding insulation. Air tightness is hard problem to address for existing houses.

Spray foam pays for itself, so it's basically free in the long run. Interesting enough people don't bat an eye when someone quotes them 20-30 k for a new Kitchen but if you quote someone 20-30 k to insulate their entire house they look at you like you killed their mother and sister.

The average home has 2000 ft of linear cracks. Everything from poorly sealed doors, windows, and envelope. It's like the equivalent of keeping your front and back door open all year around. So even after spray foaming there is some leakage (blown door test).

Really, Spray foam isn't that expensive, you should be paying about $3 -$4 a sq/ft at around a R-21 which is cheaper than most tile or carpet installations.

https://huntsmanbuildingsolutions.com/en-US/

If I were building a house I would probably go with ICF forms all the way up and Spray Foam the attic and basement floor (under the concrete floor). If I were renovating, I would Spray Foam and try to make the job large enough to cover the contractors minimum charge. Even a couple of rooms can really help the utility bills.

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

#272

Post by ClumsyPilot »

jaclaz wrote: post #141
Sankozi wrote: post #113

Earlier quoted context omitted.

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

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…

"You essentially have a "break even" point 20 years in the future, from there onwards you start saving money."

That's exactly how a 5% roi investment works. There is nothing unusual here.

"in less than 20 years time it is possible that someone comes out with a mega-para-hyper-ultra climatization device that makes yearly energy costs go down by (say) 90%"

And it's possible second coming of Christ will happen, or an asteroid will fall, and you'd be better off soending money on hookers and cocaine.

A plan that relies on some unrelated events to solve your problems is not a plan. Why bother planning at all then?

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

#273

Post by danans »

jwr wrote: post #109

While this is at the extreme end of the spectrum, there is a much easier way to save lots of energy: just build modern well-insulated homes. I lived in California and I was appalled at the monstrous energy waste: houses are generally made pretty much from cardboard. You need to cool them in summertime and heat them in wintertime, and the energy expenditure is enormous. I now live in Poland and have recently built sma…

>I lived in California and I was appalled at the monstrous energy waste: houses are generally made pretty much from cardboard. You need to cool them in summertime and heat them in wintertime,

This is the legacy of historical low energy prices coupled with a historically mild climate.

Now, both of those things are changing. Energy prices are rising because of global warming accelerated risks, and simultaneously the climate is getting hotter and dryer.

The result is that it can start making sense to build to a higher standard like passive house in CA - I just did and my HVAC energy usage dropped 75% and is now more comfortable.

However, there needs to be better code enforcement - i.e. air leakage for new homes should be closer to 2.0 ACH50, not the totally unenforced 5.0 ACH50 on the books today - and also better education of buyers so they can start demanding better built and more efficient homes.

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

#274

Post by driverdan »

k__ wrote: post #245
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…

A friend of mine, who is an architect, told me the technology is ripe to build houses that produce even more energy than they consume, but people simply don't want to live in them. The article talks about "using the best windows", the problem my friend saw in many of such houses was simply that the dwellers would either open the windows too often, losing all the heat, or feel miserable because they weren't allowed to…

> the technology is ripe to build houses that produce even more energy than they consume, but people simply don't want to live in them

It's called solar. Unless the house has a small footprint most can fit enough solar panels to more than cover their energy use.

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

#275

Post by Retric »

jaclaz wrote: post #268
Retric wrote: post #262

Earlier quoted context omitted.

You can very much rent a passive house for significantly more by including heating and cooling costs into the rental price. People can’t see what your heating bills are but they can compare with other properties that include heating. Actual price differences at time of sale should be nowhere close to 30% not only because that’s an insane difference in construction costs but also because land isn’t free. A 200k house…

Still it remains 60K difference, or 20 years at 3K.

Assuming it is actually 60k, where in reality insulation is cheap. Having giant windows is useful for passive heat gain, but their mostly installed for aesthetics not practicality. Which means aesthetics are also increasing home values.

In terms of pure economics an extra 15k in insulation and 15k for a solar hot water system gets you further at much lower costs by actually providing hot water for showers not just lowering heating bills.

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

#276

Post by spookthesunset »

k__ wrote: post #245
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…

A friend of mine, who is an architect, told me the technology is ripe to build houses that produce even more energy than they consume, but people simply don't want to live in them. The article talks about "using the best windows", the problem my friend saw in many of such houses was simply that the dwellers would either open the windows too often, losing all the heat, or feel miserable because they weren't allowed to…

> A pure psychological effect of course, even with the best ventilation people still had the urge to open a window and felt bad if they couldn't.

I wouldn't want to live in a house where I couldn't open the windows all the way. Near-perfect energy efficiency is something to strive for but there is something to be said for being able to open the window and get a nice breeze blowing through the house. Even if it isn't the most energy efficient it's okay with me.

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

#277

Post by spookthesunset »

k__ wrote: post #245
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…

A friend of mine, who is an architect, told me the technology is ripe to build houses that produce even more energy than they consume, but people simply don't want to live in them. The article talks about "using the best windows", the problem my friend saw in many of such houses was simply that the dwellers would either open the windows too often, losing all the heat, or feel miserable because they weren't allowed to…

> A pure psychological effect of course, even with the best ventilation people still had the urge to open a window and felt bad if they couldn't.

I wouldn't want to live in a house where I couldn't open the windows all the way. Near-perfect energy efficiency is something to strive for but there is something to be said for being able to open the window and get a nice breeze blowing through the house.

Even if it isn't the most energy efficient it's okay with me. I mean if we really wanted to get good energy efficiency we'd just remove all the windows completely. But we don't because we design building for the enjoyment of humans, not just for energy efficiency.

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

#278

Post by kwhitefoot »

em-bee wrote: post #219
poseva wrote: post #202

Earlier quoted context omitted.

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…

The average size of homes in the UK is under 80 m2. See https://shrinkthatfootprint.com/how-big-is-a-house

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

#279

Post by gruez »

shalmanese wrote: post #265

People fail to appreciate how much leveraged financing affects the design of houses. If you pay 100% for a house and you decide to build something only you appreciate using 10% of your budget, you will lose 10% of your investment when selling the house. If you put down 20% and have the bank finance 80%, then the same decision will wipe out 50% of your investment. This means for financed houses, "resale value" becomes…

>That's why, paradoxically, in countries much poorer than the US/UK/Aus/NZ, you see much better building quality because their finance systems are also less developed.

source? China isn't well known for their well built buildings for example.

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

#280

Post by jaclaz »

Retric wrote: post #275
jaclaz wrote: post #268

Earlier quoted context omitted.

Still it remains 60K difference, or 20 years at 3K.

Assuming it is actually 60k, where in reality insulation is cheap. Having giant windows is useful for passive heat gain, but their mostly installed for aesthetics not practicality. Which means aesthetics are also increasing home values. In terms of pure economics an extra 15k in insulation and 15k for a solar hot water system gets you further at much lower costs by actually providing hot water for showers not just lo…

I think you are downsizing the project, from investing 60K to save 3K/year to investing 30K to save 1.5K/year.
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