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 of EPS graphite, underfloor 45 cm EPS and on the roof, 50 cm and the orientation is full on south. For heating it consumes about 1500-2000 kWh per year (December, January, February and a maybe a small part of March)
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.
Have a look here [0], this is the first PassivHaus in my area and is nicely documented.
The cost of building a PassivHaus in my country typically goes about 20-25% more than a traditional one.
People doesn't give the massive importance the isolation has. Some years ago we remodelled our home and added XPS (Extruded Polystyrene) to insulate the roof of the house. After that we use the AC only three or four days in the year, and before that we had to use it at least a complete summer month. That house is in the south-interior of Spain, so heat is no joke here.
If somebody are constructing or remodelling any house I recommend it to add any insulation they can in any shape, in less than five years you'll recover what you spend, and if you add PV panels for electricity or a thermosiphonic system to heat water, you'll recover the investment in about 10 years, with a healthy amount of available health in the devices to continue saving money with a proper maintenance.
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.
We’ve just built a 45m2 log cabin to passive standards here in Portugal - heavily insulated in walls, floor, roof, lifted off the ground on concrete columns, double glazed, only heat source is a 2.5kw log stove. Everyone here (who all live in uninsulated concrete houses heated by open fireplaces) said we will freeze in the winter, roast in the summer. We situated the house on a north facing slope, to minimise sun exposure in the summer. Means little direct light in the winter, but we think (have yet to experience a summer in it) the balance will be good.
As I write this, the stove is out, having burned out overnight, it’s -11 outside, and 25 inside. We are getting through a ridiculously tiny volume of firewood compared to when we were living in a more traditional house for here - less than ⅛ the volume.
Insulation works. It’s also cheap. I don’t understand why people would build new structures without it.
> 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):
You do not need concrete† and masonry to make homes efficient. Switching from using 2x4s @16" off centre (OC), to 2x6 @24" OC ("advanced framing") would allow for less wood use, less thermal bridging, and more cavity space for insulation.
† It should be noted that concrete creates a lot of CO2 emissions, as does baking bricks. Growing wood on the other hand is a way to sequester carbon.
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 open the windows. 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.
Salut! Could you please share more info / photos / tips, besides the sdac.ro link?
How high is the elevation? What kind of heating do you use? How do you refresh the air? (opening the windows or heat recovery system)
Thanks
So with home solar panels and storage getting cheaper and cheaper and better and better, where is the optimization point of investing in better insulation vs just buying more solar panels?
Especially if the solar panels may produce profit on sunny mild days about 40-50% of the year if there is reverse metering and the like?
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 small homes that are similar in structure to the ones in CA: wooden frame, drywall inside. But the ones here have walls that are 25cm thick because of insulation (mineral wool) and use advanced modern membranes as well. Together, these things do wonders, and maintaining warmth in wintertime using a heat pump (AC) is easy and doesn't cost an arm and a leg.
In other words, you can get 80% of the benefits with 20% of the effort — just design thicker walls with insulation and use modern materials.
>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.
Echoing the sentiment, it cost significantly more for me to heat a studio to 65F in CA than to get a 2/1 up to 72F in ND (or rather, to maintain those temperatures).
Both units had electric baseboard heat and were top floor apartments, but the CA unit didn't have double pane windows, had enormous gaps at the doors and windows, and for all intents and purposes didn't have any insulation. If it was warmer than 0F or so outside the ND unit would have more than enough heat just from cooking. If it was colder than 50F or so the CA unit needed the heaters to actually be on.
Coming from a decidedly unsexy post-industrial Midwestern city, I was very surprised to learn that for all the wealth and splendor of California, most of the buildings here seem horribly impoverished.
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 the preeminent decision affecting the design of a house.
In Economics, this is known as a "Keynesian Beauty Contest" [1] where your job is to predict what everyone else predicts will be the most popular option and Keynesian Beauty Contests can get weird.
eg: It's quite possible that you might personally hate granite countertops but still feel the need to put a granite countertop in your home because you believe it will help the resale value of your home. It's quite possible for everyone in a community to all hate granite countertops but for everyone to still put granite countertops in their home because they believe everyone else loves granite countertops. It's quite possible for everyone in a community to hate granite countertops and to know that everyone else hates granite countertops and still make the economically rational decision to put a granite countertop in their house to help with the resale value.
A lot of "economically irrational" housing decisions are driven by this core transformation via Mortgage Backed Securities of a house from a consumption based purchase of a place to enjoy living into an investment asset that dominates most people's finances.
It's only in houses built for the independently wealthy that don't really care about the future resale value of their houses that a lot of the good building science expertise still lies. 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.
>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.
I'm in the middle of building a PassivHaus. The building itself is mostly done and we're working on the interior. There are still a few gaps that haven't been plugged and the heat exchangers have not yet been installed. I'm above 800m elevation, snowstorms every weekend. It's cold here. My house also actually faces West instead of South, so I'm not getting much heat from the sun. This was a surprise to use because the previous house on the same site had the same orientation and was scorching during the evenings, it's amazing what a pair of Low-E triple paned windows can do.
Despite all that, the builders manage to work inside the building with a single kerosene stove[0]. And the building stays comfortable for several hours even after the stove has been turned off.
I'm looking into making a house sustainable right now and the windows are actually a point of contention. One side thinks super-high insulated (triple pane) windows are a waste of money, the other swears by them. Assuming the frame doesn't leak, does triple really make that much of a difference?
How is the ventilation and air quality? I work in a passive house in and we're experiencing significant issues with the indoor air quality when the building HVAC turns low.
For heating a home efficiently, one approach is a rocket mass heater. It does require burning firewood, but if that's an acceptable/desirable quality, this technology seems far more efficient than standard fireplaces.
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 thick which I'd have expected to be a good insulator but in reality they're a thermal bridge.
For generation, I've reserved a spot in Rippleenergy's next co-op turbine [0]. I've been looking into PV/solar thermal/solar battery combinations as well as heat batteries. Sunamp's looks interesting [1] and phase change materials in general. Living in a high latitude (Scotland) the benefit in Winter is more marginal but I'd be happy with simply covering the cost and having peace of mind where the energy came from. PVT panels look interesting if not well-known/scarce.
There's so many parts to the answer it seems like energy advisors could be more of a thing in the same way financial advisors are plentiful.
I wish more municipalities would mandate tighter homes with good ventilation. Recently when searching for a new home it was so dishearting to see brand new developments where the homes had standard insulation, bad orientation for things like solar and passive heating and giant fossil fuel based heating systems instead of heat pumps. I decided to instead go the oppostie direction and buy a 1960’s split level that I am modernizing.
It’s been quite a challenge to retrofit, we really need to be building to a higher standard for new stock. While renewable energy is all the rage this rarely gets a mention.
In America the latest building craze seems to be a veneer of beauty over bad functional design, and a strong mentality of "fuck you pay me" from the seller.
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.
I think this is one of those things where people generally agree that better insulation and lower energy costs is a good thing but who pays for it?
In the UK, there is a constant demand for "affordable housing", which is caused by governments not controlling the housing market from either foreign investors or also people using the housing bubble to buy up loads of properties over time forcing others to rent.
Bearing in mind how much profit a lot of home builders make, increasing the regulations is likely to add at least £20K to a basic house, significantly more if you include mechanical ventilation, triple-glazed windows and heat pumps (perhaps +£50K), which is some cases will be 50%+ of the original cost!
Another major problem is the quality of building in the UK, mainly driven by a lack of tradespeople, and simply not having the skills to install to the quality levels required by thermally efficient houses like installing a membrane with zero holes in it, using the correct tapes, designing, installing and maintaining heat pumpes and various other things.
I think these challenges will get better over time but that is probably why governments aren't keen to make large improvements in energy-efficiency regulations.
>Bearing in mind how much profit a lot of home builders make, increasing the regulations is likely to add at least £20K to a basic house, significantly more if you include mechanical ventilation, triple-glazed windows and heat pumps (perhaps +£50K), which is some cases will be 50%+ of the original cost!
The sales price of houses in the UK (and elsewhere) is driven by the market and there is a low amount of released, buildable land and a lot of demand in the Southeast. The land value (a large component of the value) is not actually set in an independent market but is based on the expected sales price minus construction costs and development costs. Therefore increasing the built cost of properties will decrease the value of land likely to receive planning permission without affecting purchase price by much.
The marginal cost of thicker walls is also very low (especially compared to retrofit costs) so the impact on construction cost is nothing like £50k.
> I think these challenges will get better over time but that is probably why governments aren't keen to make large improvements in energy-efficiency regulations.
This is probably true but it's still backwards. The state should want to improve the affordability of housing and should consult with industry on which measures can be introduced but ultimately the state must introduce the new regulations to help drive the market in the direction of continuous improvements to the housing stock's long-term affordability. I think if they shirk this then they simply aren't doing the job properly.
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, insulation layer, and a pretty brickwork or brickwork-looking facade.
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
>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?
People making decisions about which contractor to use (both for public and private projects) are often mandated to choose the absolute cheapest bidder, sometimes with the ability of choosing a different one if they file mountains of paperwork explaining why.
I doubt the maintenance part. I lived in one and experienced more maintenance. You have the heat exchanger as an additional moving part which needs cleaning, new filters, etc.
Also, you need a perfect seal between inside and outside. So any cables going outside (blinds, air conditioning which you'll still want if it's 40C outside, etc) needs to be sealed and is thus much harder to replace or repair.
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, as well, which is why they built the walls so thick.
They poured the basement foundation on top of layers of foam insulation, and used piers (I don't know what they're called) down to the bedrock for structural integrity; the majority of the outside of basement floor was in contact only with insulation. Only 16-20 8" columns went through the insulation down to bedrock and could be good conduits for heat to the earth. All of the walls in the basement were double insulated from the earth they held back.
That house was heated entirely by the heat that the water heater released through its insulation. Once or twice a year they would light a candle on the dining room table, to bring the heat back up if it ever got below what they felt was comfortable. Most days they had windows cracked open on opposite sides of the house in the middle of winter because it got too hot even with the furnace turned off entirely. It was never less than 75F in that house, even when it was -15F outside. I spent months on end in that house, just wondering when the furnace would come on. It never did. Not once while they lived there was the furnace ever needed. They lived in Missouri, US.
Years later my grandfather realized that he had left the petcock which allowed hot water to circulate to the radiator over which air was blown and heated to circulate heat throughout the house closed for over a decade -- since the house was built. "I knew I wouldn't need this damn furnace. Building code requires it, and I fought that but lost."
If you're careful, thoughtful, and determined, you can make a little bit of heat go a very long way. They were tired of paying heating bills. They paid to get rid of them, but they were rid of them.
While I certainly dream of building a true passive house, it is much more reasonable to follow the Pretty Good House approach, in it's current 2.0 version described here: https://www.prettygoodhouse.org/pgh-20
As with most engineering efforts, the last 20% of optimization tend to be costly. But covering the basics (mainly around insulation and air-sealing) has a huge impact already without increasing upfront costs by the same ratio.
Also the wall/roof assembly needs to match the climate for the region, mainly because of the dew point and how it relates to temperature and moisture differences between inside/outside. https://en.wikipedia.org/wiki/Dew_point
Reminds me of 'Earthship Houses' that are completely off grid, recycle their waste water to grow crops, are built using repurposed car tires and grow their own food.
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 heat" as it were, she is not comfortable.
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.
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?
In Austria an architect build an office building completely without any heating at all [1]. And now after the first experiences he is doing it for clients as well [2]. It works.
> Our designs combine generous ventilation with high insulation (140mm-thick wall framing combined with R4 wall insulation in the North Island – far above the Building Code requirements)
NZ North Island is pretty extreme in its non-extremeness. It's near perfect for building homes that don't need excessive heating and cooling.
From a global perspective, 140mm insulated framing is nothing. In any colder climate (such as the nordics) or hotter climate (such as the south US or southern Europe) a comfortable well-insulated wooden frame home needs at least 300mm insulation. That's also the code in e.g. Sweden.
Checkout poroton, as a building material it is near impossible to beat - high insulation, low total cost, humidity seeps slowly thorugh the walls and termal mass is massive
> Even in places known for their extreme weather conditions – such as ‘hot ‘n’ cold’ Otago, wind-prone Wellington and sweaty Auckland – high-performance homes will stay comfortable and fresh all the year round.
All these places stay above 45F and below 80F. This is anything but extreme weather. You don't need any sort of special "high performance" house for this kind of temperate climate.
They mention that they avoid over sealing, for local climate reasons but an interesting technique/gadget for sealing the air barrier is to vapourize some caulk type stuff in the air and force air in through a fan. As the air escapes through small holes it fills them.
Apparently without this you need to be very careful while building, while this lets you go a little faster and sort it out after.
There's also a recent development where just slapping on some solar panels can sometimes make more sense than extra insulation, in terms of cost and return.
[+] [-] poseva|4 years ago|reply
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 of EPS graphite, underfloor 45 cm EPS and on the roof, 50 cm and the orientation is full on south. For heating it consumes about 1500-2000 kWh per year (December, January, February and a maybe a small part of March)
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.
Have a look here [0], this is the first PassivHaus in my area and is nicely documented. The cost of building a PassivHaus in my country typically goes about 20-25% more than a traditional one.
[0]: http://www.sdac.ro/site/archives/category/passivehouse
[+] [-] jmrm|4 years ago|reply
If somebody are constructing or remodelling any house I recommend it to add any insulation they can in any shape, in less than five years you'll recover what you spend, and if you add PV panels for electricity or a thermosiphonic system to heat water, you'll recover the investment in about 10 years, with a healthy amount of available health in the devices to continue saving money with a proper maintenance.
[+] [-] kitd|4 years ago|reply
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.
This was in the UK. Colder climates may vary ofc.
[+] [-] madaxe_again|4 years ago|reply
As I write this, the stove is out, having burned out overnight, it’s -11 outside, and 25 inside. We are getting through a ridiculously tiny volume of firewood compared to when we were living in a more traditional house for here - less than ⅛ the volume.
Insulation works. It’s also cheap. I don’t understand why people would build new structures without it.
[+] [-] throw0101a|4 years ago|reply
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 personal home up to Passive House standards:
* https://www.youtube.com/watch?v=mBOvflXoWlw
You do not need concrete† and masonry to make homes efficient. Switching from using 2x4s @16" off centre (OC), to 2x6 @24" OC ("advanced framing") would allow for less wood use, less thermal bridging, and more cavity space for insulation.
† It should be noted that concrete creates a lot of CO2 emissions, as does baking bricks. Growing wood on the other hand is a way to sequester carbon.
[+] [-] k__|4 years ago|reply
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 open the windows. 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.
[+] [-] mariushn|4 years ago|reply
[+] [-] AtlasBarfed|4 years ago|reply
Especially if the solar panels may produce profit on sunny mild days about 40-50% of the year if there is reverse metering and the like?
[+] [-] goodpoint|4 years ago|reply
Is that correct? 99 is not small at all.
[+] [-] bserge|4 years ago|reply
[deleted]
[+] [-] jwr|4 years ago|reply
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 small homes that are similar in structure to the ones in CA: wooden frame, drywall inside. But the ones here have walls that are 25cm thick because of insulation (mineral wool) and use advanced modern membranes as well. Together, these things do wonders, and maintaining warmth in wintertime using a heat pump (AC) is easy and doesn't cost an arm and a leg.
In other words, you can get 80% of the benefits with 20% of the effort — just design thicker walls with insulation and use modern materials.
[+] [-] danans|4 years ago|reply
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.
[+] [-] bogle|4 years ago|reply
Good to see nothing's changed!
[+] [-] hansvm|4 years ago|reply
Both units had electric baseboard heat and were top floor apartments, but the CA unit didn't have double pane windows, had enormous gaps at the doors and windows, and for all intents and purposes didn't have any insulation. If it was warmer than 0F or so outside the ND unit would have more than enough heat just from cooking. If it was colder than 50F or so the CA unit needed the heaters to actually be on.
[+] [-] jve|4 years ago|reply
[+] [-] closeparen|4 years ago|reply
[+] [-] raxxorrax|4 years ago|reply
[+] [-] shalmanese|4 years ago|reply
In Economics, this is known as a "Keynesian Beauty Contest" [1] where your job is to predict what everyone else predicts will be the most popular option and Keynesian Beauty Contests can get weird.
eg: It's quite possible that you might personally hate granite countertops but still feel the need to put a granite countertop in your home because you believe it will help the resale value of your home. It's quite possible for everyone in a community to all hate granite countertops but for everyone to still put granite countertops in their home because they believe everyone else loves granite countertops. It's quite possible for everyone in a community to hate granite countertops and to know that everyone else hates granite countertops and still make the economically rational decision to put a granite countertop in their house to help with the resale value.
A lot of "economically irrational" housing decisions are driven by this core transformation via Mortgage Backed Securities of a house from a consumption based purchase of a place to enjoy living into an investment asset that dominates most people's finances.
It's only in houses built for the independently wealthy that don't really care about the future resale value of their houses that a lot of the good building science expertise still lies. 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.
[1] https://en.wikipedia.org/wiki/Keynesian_beauty_contest
[+] [-] gruez|4 years ago|reply
source? China isn't well known for their well built buildings for example.
[+] [-] SenHeng|4 years ago|reply
Despite all that, the builders manage to work inside the building with a single kerosene stove[0]. And the building stays comfortable for several hours even after the stove has been turned off.
[0]: https://nimmi.jp/kurashi-stove/
[+] [-] osobo|4 years ago|reply
[+] [-] spiffistan|4 years ago|reply
[+] [-] yboris|4 years ago|reply
https://en.wikipedia.org/wiki/Rocket_mass_heater
[+] [-] sambeau|4 years ago|reply
[+] [-] inovica|4 years ago|reply
[+] [-] ricardo81|4 years ago|reply
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 thick which I'd have expected to be a good insulator but in reality they're a thermal bridge.
For generation, I've reserved a spot in Rippleenergy's next co-op turbine [0]. I've been looking into PV/solar thermal/solar battery combinations as well as heat batteries. Sunamp's looks interesting [1] and phase change materials in general. Living in a high latitude (Scotland) the benefit in Winter is more marginal but I'd be happy with simply covering the cost and having peace of mind where the energy came from. PVT panels look interesting if not well-known/scarce.
There's so many parts to the answer it seems like energy advisors could be more of a thing in the same way financial advisors are plentiful.
[0] https://rippleenergy.com/
[1] https://sunamp.com/thermino-thermal-storage-for-domestic-hot...
[+] [-] mcot2|4 years ago|reply
It’s been quite a challenge to retrofit, we really need to be building to a higher standard for new stock. While renewable energy is all the rage this rarely gets a mention.
[+] [-] jsiaajdsdaa|4 years ago|reply
[+] [-] mdp2021|4 years ago|reply
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.
[+] [-] lbriner|4 years ago|reply
In the UK, there is a constant demand for "affordable housing", which is caused by governments not controlling the housing market from either foreign investors or also people using the housing bubble to buy up loads of properties over time forcing others to rent.
Bearing in mind how much profit a lot of home builders make, increasing the regulations is likely to add at least £20K to a basic house, significantly more if you include mechanical ventilation, triple-glazed windows and heat pumps (perhaps +£50K), which is some cases will be 50%+ of the original cost!
Another major problem is the quality of building in the UK, mainly driven by a lack of tradespeople, and simply not having the skills to install to the quality levels required by thermally efficient houses like installing a membrane with zero holes in it, using the correct tapes, designing, installing and maintaining heat pumpes and various other things.
I think these challenges will get better over time but that is probably why governments aren't keen to make large improvements in energy-efficiency regulations.
[+] [-] Mvandenbergh|4 years ago|reply
The sales price of houses in the UK (and elsewhere) is driven by the market and there is a low amount of released, buildable land and a lot of demand in the Southeast. The land value (a large component of the value) is not actually set in an independent market but is based on the expected sales price minus construction costs and development costs. Therefore increasing the built cost of properties will decrease the value of land likely to receive planning permission without affecting purchase price by much.
The marginal cost of thicker walls is also very low (especially compared to retrofit costs) so the impact on construction cost is nothing like £50k.
[+] [-] bogle|4 years ago|reply
This is probably true but it's still backwards. The state should want to improve the affordability of housing and should consult with industry on which measures can be introduced but ultimately the state must introduce the new regulations to help drive the market in the direction of continuous improvements to the housing stock's long-term affordability. I think if they shirk this then they simply aren't doing the job properly.
[+] [-] Mromson|4 years ago|reply
My personal interest in passive buildings generally revolve around maintenance. Passive houses seem to require far less maintenance.
[+] [-] Cthulhu_|4 years ago|reply
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, insulation layer, and a pretty brickwork or brickwork-looking facade.
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
[+] [-] sb057|4 years ago|reply
People making decisions about which contractor to use (both for public and private projects) are often mandated to choose the absolute cheapest bidder, sometimes with the ability of choosing a different one if they file mountains of paperwork explaining why.
[+] [-] lostlogin|4 years ago|reply
New Zealand is savage on exposed timber. I have tried multiple products from expensive to cheap and have the same result on all.
A deck which gets rain and faces north west needs re-coating every 6 months to 1 year. The combination of heat, UV and water is just savage.
[+] [-] dx034|4 years ago|reply
Also, you need a perfect seal between inside and outside. So any cables going outside (blinds, air conditioning which you'll still want if it's 40C outside, etc) needs to be sealed and is thus much harder to replace or repair.
[+] [-] LunaSea|4 years ago|reply
Interesting! Could you explain a bit more on how you came to this conclusion?
[+] [-] naikrovek|4 years ago|reply
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, as well, which is why they built the walls so thick.
They poured the basement foundation on top of layers of foam insulation, and used piers (I don't know what they're called) down to the bedrock for structural integrity; the majority of the outside of basement floor was in contact only with insulation. Only 16-20 8" columns went through the insulation down to bedrock and could be good conduits for heat to the earth. All of the walls in the basement were double insulated from the earth they held back.
That house was heated entirely by the heat that the water heater released through its insulation. Once or twice a year they would light a candle on the dining room table, to bring the heat back up if it ever got below what they felt was comfortable. Most days they had windows cracked open on opposite sides of the house in the middle of winter because it got too hot even with the furnace turned off entirely. It was never less than 75F in that house, even when it was -15F outside. I spent months on end in that house, just wondering when the furnace would come on. It never did. Not once while they lived there was the furnace ever needed. They lived in Missouri, US.
Years later my grandfather realized that he had left the petcock which allowed hot water to circulate to the radiator over which air was blown and heated to circulate heat throughout the house closed for over a decade -- since the house was built. "I knew I wouldn't need this damn furnace. Building code requires it, and I fought that but lost."
If you're careful, thoughtful, and determined, you can make a little bit of heat go a very long way. They were tired of paying heating bills. They paid to get rid of them, but they were rid of them.
[+] [-] dakna|4 years ago|reply
As with most engineering efforts, the last 20% of optimization tend to be costly. But covering the basics (mainly around insulation and air-sealing) has a huge impact already without increasing upfront costs by the same ratio.
Also the wall/roof assembly needs to match the climate for the region, mainly because of the dew point and how it relates to temperature and moisture differences between inside/outside. https://en.wikipedia.org/wiki/Dew_point
[+] [-] dhruval|4 years ago|reply
There is a community in New Mexico https://www.youtube.com/watch?v=wgUkjbMhF18
And even some in Canada https://www.youtube.com/watch?v=EAvY5JeMz9w&t=62s
[+] [-] mattlondon|4 years ago|reply
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 heat" as it were, she is not comfortable.
[+] [-] Terry_Roll|4 years ago|reply
[+] [-] tigerlily|4 years ago|reply
Yet we build them this way over and over and over and over and over and over and over and over...
[+] [-] londons_explore|4 years ago|reply
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?
[+] [-] PinguTS|4 years ago|reply
[1] https://www.detail-online.com/article/house-without-heating-...
[2] https://www.world-architects.com/en/baumschlager-eberle-arch...
[+] [-] alkonaut|4 years ago|reply
NZ North Island is pretty extreme in its non-extremeness. It's near perfect for building homes that don't need excessive heating and cooling. From a global perspective, 140mm insulated framing is nothing. In any colder climate (such as the nordics) or hotter climate (such as the south US or southern Europe) a comfortable well-insulated wooden frame home needs at least 300mm insulation. That's also the code in e.g. Sweden.
[+] [-] bythreads|4 years ago|reply
[+] [-] dahfizz|4 years ago|reply
All these places stay above 45F and below 80F. This is anything but extreme weather. You don't need any sort of special "high performance" house for this kind of temperate climate.
[+] [-] ZeroGravitas|4 years ago|reply
Apparently without this you need to be very careful while building, while this lets you go a little faster and sort it out after.
https://www.finehomebuilding.com/2013/05/15/a-shortcut-for-a...
There's also a recent development where just slapping on some solar panels can sometimes make more sense than extra insulation, in terms of cost and return.