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Next week's episode looks better? More problems 🤣
What did I just see at the end? 😂
I think more data is needed rather than just pointing a thermal imaging camera at the house 🤔.
Another visit in a few years with a look at all the energy bills would be good.
I'm a big fan of earthships and passive features. I thought this was a good go at things...
However, as he stated 'we only need 14 or 15*c of radiated heat' while wearing three layers of clothes, I did wonder. 🤔
Then we saw the stove and the pipes that originally in the plan were air filled (as many earthships use) were now underfloor heating led to a manifold area and pumps. And so I wondered more. 🤔
I'm keen to see the data from this one. Totally passive heat gain and conservation seems just out of reach in much of the UK - but I'm happy to be corrected.
And first programme in a while without pregnancy (although kev flirted with her), without £100k sofa and without huge window delays...
Felt a bit let down. I liked the whole low impact idea. Can reconcile the concrete/polymers for lower fuel burn (actually thinking about it not so sure) But it all went a bit slick and expensive suddenly. She even had to go to work to afford stuff.
£300k sounded good but no outlay for the 3 acres. What will be the mass of that roof with waterlogged soil? And how much will thermal insulation degrade with compaction of soil and expanded polystyrene?
Thermal imaging was just bollocks without scaling. Depending on the scaling you could have 20degrees be orange or blue. You could even move the scale to change the colours in the image to suit you.
Does the place not become unbearably hot in the summer or is all that earth and concrete heat sink actually going to cool the place down enough?
Anyone know where the house is?
Spent £45k (?) on windows and she was applying the sealant herself. I'm keen on DIY but wouldn't trust myself to get the finish I wanted!
Beautiful space inside. Hopefully they can have all the glass open in the summer to bring the outside in.
Did anyone else notice that Kev was wearing slippers inside?
Would love to see an update, especially without any spin on the figures.
Grand designs used to have interesting projects at realistic prices. Like the eco house built by the "woodsman" and my fave the young couple that bought a redundant pumping station and converted it to an interesting house. all seems to be hugely expensive and complex stuff nowadays
Some friends of mine bought a house in ireland that was a grand designs ireland house. they love it and bought it at a realistic price. Its an interesting building while still being practical but my bet is the builders made a huge loss on it
Hmmm, only caught the walk around and the cabaret spectacular at the end. I will have to re-look at this one.
I only ever watch the walkaround. then if i like it ill go back and watch the brief/3D model stuff. never bother with the middle half hour.
I'm not sure how many times he said it was his show case for his business. Enough to make it an advert, hence the slick furniture.
He might be relying on a bit of global warming to bring those average temps up, 14 degrees C is not a comfortable temp.
Anyone know where the house is?
Programme said Buckinghamshire, newspapers say Bletchley but I think it's actually in Great Brickhill. I can't imagine how he did that for £310k at Buckinghamshire prices, even if he did already have the plot. As always a breakdown of costs would be really interesting to see, I suspect there must have been a fair amount of mates rates stuff.
The duet at the end completely caught me off guard, how random 😆. And brilliant.
Could use Rightmove to cyber stalk the bunkers location cos the family house was going up for sale wasn't it?
I’m keen to see the data from this one. Totally passive heat gain and conservation seems just out of reach in much of the UK – but I’m happy to be corrected.
Our neighbours are near passive (built to that spec but not 'certified'). No heating system, just a couple of 1kw plug in electric heaters that they rarely need to use. If you insulate and airtight well enough you can save the cost and embedded energy of a complex heating system.
Looks like it's the one to the west of the southern end of Great Brickhill Lane/Green End junction. Nice plot to have - think I said that about last weeks 🤔
How does airflow work in a building like that? Is it a constant battle between letting fresh air in and letting all that hard earned heat out?
I guess you can use extractor fans and dehumidifiers but it’s never going to be as “fresh” as leaving a few windows open
I too would be interested to see if it works as advertised. It has been done in Iceland in the past so in theory it should work in the U.K. unless they rely on the geothermal gain from the ground
Does the place not become unbearably hot in the summer or is all that earth and concrete heat sink actually going to cool the place down enough?
The thermal mass of the soil and concrete, helps moderate the peaks. It will help maintain a very steady temperature year round, once it has got upto 'working conditions' over the two years. It is a fine balancing act at design stage.
What will be the mass of that roof with waterlogged soil? And how much will thermal insulation degrade with compaction of soil and expanded polystyrene?
I am sure the wet soil load will have been calculated.
The thermal insulation is so massive in size that although it will degrade with wet, or even in 50 years time when the foam starts to degrade, it will be enough. I expect he will have calculated these things. We used to calculate how many times a day the loo was flushed with cold incoming water - and account for it in the heating requirements.
No heating system, just a couple of 1kw plug in electric heaters that they rarely need to use. If you insulate and airtight well enough you can save the cost and embedded energy of a complex heating system.
In a past life I have supplied insulation (and more) materials to about 30 Passiv Haus or AECB Gold+ projects. My comment still stands - your friends have those small boost heaters. I have spent a few days in PassivHaus or equivalent builds, and things like using the home gym or a family of 5 all having showers within an hour causes real issues for the temperatures in the building. You end up needing MVHR/small heaters/boosted ventilation etc to help manage some of the peaks.
If I ever get to self-build, it will be to a huge passive thermal performance, but I will still have good MVHR, user active systems (open a window!) and some heat input.
And if anyone wants to see a database of such low energy buildings, see https://www.lowenergybuildings.org.uk
How does airflow work in a building like that? Is it a constant battle between letting fresh air in and letting all that hard earned heat out?
Heat recovery ventilation - there are 'passive' versions without fans but they're more unusual.
I have spent a few days in PassivHaus or equivalent builds, and things like using the home gym or a family of 5 all having showers within an hour causes real issues for the temperatures in the building. You end up needing MVHR/small heaters/boosted ventilation etc to help manage some of the peaks.
Real issues in what sense? We have fewer problems with overheating when we have people round here than we did in an old house. Key is to have very low temperature heating (rather than hot radiators) so that the heat input is self limiting.
Does the place not become unbearably hot in the summer or is all that earth and concrete heat sink actually going to cool the place down enough?
Not only that, but they *have* to make it unbearably hot in the summer: "keep the doors closed, we need to keep the heat in for the winter" on a hot summer day
Real issues in what sense?
I may have heard it wrong, and I may be off on this, but...
Part of the earthship principle is to minimise/remove 'active' systems such as heating or mechanical ventilation where possible. This mainly works in very dry and hotter (in the day) environments.I thought last night's GD build was along this principle.
There's nothing wrong with needing these systems, and in fact my view was that in the UK with our mild and wet environment they are a necessity.
It's just not as passive as many folk think and GD last night seemed to suggest.
Not only that, but they *have* to make it unbearably hot in the summer: “keep the doors closed, we need to keep the heat in for the winter” on a hot summer day
Not necessarily - being so massive in thermal terms the building should maintain a steady temperature almost year around, hot or freezing days included.
The heat doesn't 'come in' through air temperature or glass - it 'comes in' through the ground around and on top of the building.
The heat doesn’t ‘come in’ through air temperature or glass – it ‘comes in’ through the ground around and on top of the building.
In summer? I misunderstood that then - I thought it was sun through the windows, trapped then as heat and absorbed by the uninsulated earth walls, with the insulation on top of the soil to ensure it doesn't radiate back into the atmosphere
So how many years before the carbon used to build it is offset by living in a fridge?
Less time than a 'normal' house. 😉
The thermal insulation is so massive in size that although it will degrade with wet, or even in 50 years time when the foam starts to degrade,
I'd be more concerned about the compaction of the expanded polystyrene under the weight of the soil in 10/20 years, well before it starts to break down in 500 years. Flipping dreadful stuff.
Yeah my concern was compaction.
I really liked the central part and the way it was used for light.
This internal fit of walls looked a bit shopfitters. I wonder how much the soil mass heating is dependent on heating from inside the house and how inside walls alter that.
The idea is pretty ancient cave houses are nicely cool in summer and warmer in winter.
It looked like a ground source heating system in there. Didnt the 'flypast' plan shows a lot of pipes going in the ground around the property?
Thats the impression I got, a pump would be running in the summer to heat up the ground around the house in the summer,taking heat from the sun on the internal floors, then do the reverse in winter. It was glossed over a bit, maybe a very basic Ground Source heating, but with loads of pipes?
There was no mention of any ventilation system and with walls at only 14 degrees there will likely be mould growth. They had a lot of sliding doors with terrible air tightness and also bad thermal performance. This house shouldn’t be confused with the German passive house standard as it would no way pass any of the standards. The crazy thing is if he wrapped the slab and concrete walls in insulation, put in better doors and windows and an Mvhr he could have easily had a proper Passivhaus that are well proven to work and only need a very small heat input in winter. I didn’t really understand what was going on with the floor as the claim was to store heat under the slab, followed up by showing someone stapling ufh pipes into what looked like insulation that would prevent that heat store effect.
Tracked down the planning application with a bit of companies house sluthing -
Thought it was going to reveal a heating system, but not that I can see! I quite liked the house, though 14 degrees seems pretty cold to me
The crazy thing is if he wrapped the slab and concrete walls in insulation, put in better doors and windows and an Mvhr he could have easily had a proper Passivhaus that are well proven to work and only need a very small heat input in winter.
Yes, but he was trying something new (based on an old principle). Someone was the first person to build a Passivhaus, once. This is Grand Design to me; Someone building what they want because they can't buy it. It was flawed and I am skeptical about it working, too, but good luck to him.
Looking forward to next week
Good on him but he was clearly nuts. I am not sure how happy his family was going to be having been sold the dream of not needing heating and then living in 15 degrees.
I would have thought it would have had some sort of "air lock" for cold weather access rather than a sliding door straight in to that massive void of a living space.
If the walls are warm then I guess that the air temp can be lower if the humidity is controlled, but 14°C wasn't tropical.
I thought that the program edit made him look a bit "odd". Maybe he was. Dunno.
matt_outandabout
Full Member
Less time than a ‘normal’ house. 😉
I would have liked to have seen the calculations. That was a lot of concrete pouring, digger driving, earth moving, lorry driving building. And for 14 degrees. **** that. If he doesnt compliment it with something, the next owner will.
I liked the house. I just dont think it's a realistic endeavour in this country to produce low carbon homes en masse. The odd one here and there due to the cost of the builds isn't going to make a difference.
I really should watch this rather than commenting on it blind..
I would have thought it would have had some sort of “air lock” for cold weather access rather than a sliding door straight in to that massive void of a living space.
Air doesn't actually hold much heat at all. This isn't a very scientific description but my experience is that in an old, poorly insulated, house you're relying on hot air to keep you warm - the uninsulated structure of the building is always much cooler than the air. When you open a door and dump all the warm air from the house it takes some time for the heating system to warm it all up again. (our old house had a suspended wooden floor at ground level, with more cold air underneath)
In a really well insulated house with a decent amount of thermal mass it's completely different. The walls and floor are "warm" and will quickly warm the air within if you swap it for cold air. That effect is obviously going to be lessened if your'e running the house at 15C rather than 20C....
His wife had clearly been using some of her cosmetic procedures on herself by the end! Super smooth forehead
I don’t get that house at all. So much effort and cost to remove the need for any form of heating. I just don’t see the cost benefit win there. Surely a super insulated house with very efficient renewable energy heating would be better?
It was a proof for his future business. Cost was moot as he want to sell the idea and needed to prove it works, hence that data gathering equipment.
Thing is, the house is still warming up. Now it's finished and has people living in it, and with another full summer, it could be a much more comfortable temperature next winter.
I expect he doesn't want to artificially heat it as it would take another couple of years to work out if it could have reached and maintained that temperature itself...but if he designed your house you could pump some rads in there to begin with.
Also I can't really see that you would need to have it artificially hot in the summer... the sun energy is still warming the floor and walls even if you do have the big sliders wide open.
However I did think the same as mentioned earlier, why not a side door from a boot room for winter use so you are not letting heat out of those tall windows in the main room, and if you leave the door open for a bit it's only cooling a small area.
The duet at the end completely caught me off guard, how random 😆. And brilliant.
Would totally have missed that if not for this post, thanks! 🙂
I’d be more concerned about the compaction of the expanded polystyrene under the weight of the soil in 10/20 years
When the bridge to Foulness Island was rebuilt the new one was apparently built on polystyrene foundations and it's a big enough bridge to drive a Challenger ARRV on it's transporter over it. It must have been there for well over 35 years now
Thing is, the house is still warming up. Now it’s finished and has people living in it, and with another full summer, it could be a much more comfortable temperature next winter.
I expect he doesn’t want to artificially heat it as it would take another couple of years to work out if it could have reached and maintained that temperature itself…but if he designed your house you could pump some rads in there to begin with.
Having now watched this show to the end I'm no more convinced by the design. Yes, if you build underground you can use earth as an insulator and benefit from the residual warmth in in over winter. But it's not a design that's applicable to many sites - it needs a big site (single storey plus the insulated perimeter) and the correct aspect to benefit from the solar gain. Completely unviable in a built up area.
Plus he'd installed a full, complex, underfloor heating system with pumps, room thermostats and a mass of manifolds. Moving heat through the floors makes some sense but could have done it without most of that kit and just had it all as a single zone.
The key thing being that all that effort to save you heat input doesn't stop you needing a heat source - you still need hot water.
Our house is very well insulated, with gas heating. Bulb give me an annual statement with quarterly use. taking the Jun-September use with no heating our hot water is at least 40% of our gas consumption for the year. And we likely use more hot water in winter than summer. Plus theres only 2 of us so for a family of 4 that ratio would skew even more towards water heating.
The gas we used for heating cost us £220 for the year.