Temp Posted January 21, 2021 Share Posted January 21, 2021 https://www.theconstructionindex.co.uk/news/view/future-homes-standard-sets-new-targets-for-green-building "The Ministry of Housing has set out new energy efficiency standards that all new-build houses will be expected to meet." "...all new homes will have to have low carbon heating and be ‘zero carbon ready’ by 2025" "New homes are expected to produce 75-80% lower carbon emissions compared to current levels by 2025" "While there is nothing about upgrading the existing housing stock, the standard does set down energy requirements for extensions or building improvement/renovation works." Draft Future Homes Standard specification Floor U-value (W/m2.K) 0.11 External wall U-value (W/m2.K) 0.15 Roof U-value (W/m2.K) 0.11 Window U-value (W/m2.K) 0.8 Door U-value (W/m2.K) 1.0 Air permeability (m3/(h.m2) 5.0 Heating appliance Low-carbon heating (e.g. Heat pump) Heat Emitter type Low temperature heating Ventilation System type Natural (with extract fans) PV None Wastewater heat recovery No y value (W/m2.K) 0.05 Link to comment Share on other sites More sharing options...
tonyshouse Posted January 21, 2021 Share Posted January 21, 2021 I did respond to the consultation saying ENERGY USE REDUCTION - ENERGY DEMAND REDUCTION should be the number one priority Floor U-value (W/m2.K) 0.1 External wall U-value (W/m2.K) 0.1 Roof U-value (W/m2.K) 0.1 Window U-value (W/m2.K) 0.7 Door U-value (W/m2.K) 1.0 Air permeability (m3/(h.m2) 1 ventilation Heat recovery no more dormer windows unless U =0.1 for walls and roof same for extensions The elephant in the room seems invisible, action on the existing stock is needed (some use it leverage poorer standards for new build) 1 Link to comment Share on other sites More sharing options...
Ferdinand Posted January 21, 2021 Share Posted January 21, 2021 Agree with Tony's last comment - I have been whinging about this for some years in various places. ? My estimates are that theoretically "reasonably" well insulated homes are recent (what do we say - post 2000? or post 2010) only accumulate at about 1% of the stock per year (250k a year, 25 million stock, ish), and that each of these represents perhaps 20-50% (guestimate based on about 3 bands of EPC grading representing a halving of C02 emissions very roughly) of the emissions of an older one. I think a move from an E/F to a C is a halving of emissions roughly. There are various profiles you can do about how far various grades of stock are insulated and how much to get numbers. On this one we need to follow, Scotland and begin to think about applying the "rental EPC ratchet" (rentals likely required to be EPC C by 2030 unless a spanner is put in the works of the ratchet) to all Owner Occupied housing. That has worked in that in England rental housing is now better on the EPC scale than OO (English Housnig Survey 2 years ago) - albeit by not vey much. I think this will happen because it is the easiest way imo to hit the medium term extra C02-reduction target. And GHG is beginning to address the issue. Ferdinand Link to comment Share on other sites More sharing options...
Moonshine Posted January 21, 2021 Share Posted January 21, 2021 6 hours ago, Temp said: Floor U-value (W/m2.K) 0.11 External wall U-value (W/m2.K) 0.15 Roof U-value (W/m2.K) 0.11 Now is the time to build stocks in thermal insulation companies! I wonder if anyone has an idea of what the constructions would be to achieve these. Link to comment Share on other sites More sharing options...
Ferdinand Posted January 21, 2021 Share Posted January 21, 2021 22 minutes ago, Moonshine said: Now is the time to build stocks in thermal insulation companies! I wonder if anyone has an idea of what the constructions would be to achieve these. er .... but perhaps not Kingspan or St Gobain ?. I think 0.15 is roughly what many of us build to. eg 0.15 is Brick Outer, 120mm Celotex or 225mm EPS, and Lightweight Block Inner. So not that demanding in BH context. There's a comparison table which I will post. I have not got my head around what standards will apply to extension. Will this be the same? The thicker of the two versions of Durisol, without extra internal insulation, is about 0.15 . 1 Link to comment Share on other sites More sharing options...
Moonshine Posted January 21, 2021 Share Posted January 21, 2021 Just now, Ferdinand said: er .... but perhaps not Kingspan or St Gobain ?. true (i was about to put a comment on Grenfell but didn't) Link to comment Share on other sites More sharing options...
the_r_sole Posted January 21, 2021 Share Posted January 21, 2021 The biggest problem I can see with it is the cost of construction will massively increase to achieve those uvalues so they'll reduce the number of houses being delivered and drive up the price of new houses... in turn you'll get further away from targets because old stock will be preferred and they have given zero incentive for improving the performance of them. They haven't had the push back from their chums in the house building industry yet either so it might not make it into any formal legislation Link to comment Share on other sites More sharing options...
SteamyTea Posted January 21, 2021 Share Posted January 21, 2021 (edited) 3 minutes ago, the_r_sole said: The biggest problem I can see with it is the cost of construction will massively increase to achieve those uvalues The same argument that the automotive industry has been using for decades, but they seem to manage to produce cars to a higher standard for, in real terms, less money. The biggest problem the house construction industry has is the people they employ on site. Edited January 21, 2021 by SteamyTea 1 Link to comment Share on other sites More sharing options...
the_r_sole Posted January 21, 2021 Share Posted January 21, 2021 Just now, SteamyTea said: The same argument that the automotive industry has been using for decades, but they seem to manage to produce cars to a higher standard for, in real terms, less money. The biggest problem the house construction industry has is the people they employ. The cost of insulation isn't coming down any time soon and there isn't really an alternative way to insulate a building or redesign a building to use less insulation as they are specifying individual building elements - the way it should be approached is to require a better analysis of the whole building for it's whole life - but that's no where near as easy as saying "bang more insulation in there" Link to comment Share on other sites More sharing options...
Ferdinand Posted January 21, 2021 Share Posted January 21, 2021 This is the comparison table with past and future regs @the_r_sole. Plus doc attached. Where do you think the extra cost is? Column 3 is the interim measures to come in soon. Column 4 is the FHS, which in connection with a decarbonised power supply is the route to Zero Carbon. I'm not really sure that I see huge extra cost in the interim, though some certainly, and I think that is by design. The big changes are the low temp heating (wonder if big rads count?), and the interesting tactical thing of Wastewater HR and is that compulsory PV (would affect estate layout?), which go away again (later put them back for a route to carbon positive?), and the gas boiler ban. To me the fabric changes are not *that* ambitious. I think that including the impact of zero carbon energy supply is probably correct, as that is likely to happen first given where we are at present. There's a contrast between the huge majority of responses demanding more, more, more, and the smaller number of people living in older houses who have not taken action themselves. I think the air permeability is not ambitious enough, and perhaps also a couple of others. 2021-Government_response_to_Future_Homes_Standard_consultation.pdf 1 Link to comment Share on other sites More sharing options...
Moonshine Posted January 21, 2021 Share Posted January 21, 2021 9 minutes ago, Ferdinand said: Where do you think the extra cost is? i have just had a look at warm roof build up, using www.uvalue-calculator.co.uk as below For U value of 0.11 you would need 180mm of 0.022 W/mK PIR, for U value of 0.13 (current Part L) you would need 155mm of 0.022 W/mK PIR For a quick comparison Recticel Eurothane GP 25mm is £11.30 a sheet (£3.92 / m2). Over a 100m2 flat roof its an extra £400 in materials Link to comment Share on other sites More sharing options...
Mr Punter Posted January 21, 2021 Share Posted January 21, 2021 Over half our housing stock is flats. A quarter is terraced houses. Most of it is existing. How the hell will the heat pumps work out? Link to comment Share on other sites More sharing options...
Iceverge Posted January 21, 2021 Share Posted January 21, 2021 2 minutes ago, Mr Punter said: Over half our housing stock is flats. A quarter is terraced houses. Most of it is existing. How the hell will the heat pumps work out? 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted January 21, 2021 Share Posted January 21, 2021 2 minutes ago, Mr Punter said: Over half our housing stock is flats. A quarter is terraced houses. Most of it is existing. How the hell will the heat pumps work out? Flats could have A2A heat pumps, or community heating. Terraced places may have enough room outside for a monoblock, but could have a split system. Both flats and terraced have relatively low energy usage by definition (less exterior wall area), so a smaller problem to solve. Link to comment Share on other sites More sharing options...
ProDave Posted January 21, 2021 Share Posted January 21, 2021 For me the disappointing thing in the wish list is the air test number. I see SO MANY houses, even recent ones where you unscrew a socket from the wall and a howling icy cold gale comes out of the hole. It is my gut feeling that the best "bang for your buck" improvement would be force the builders to sort out the air tightness and install mvhr. The air tightness is not so much of a cost issue but an attention to detail issue. 3 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted January 21, 2021 Share Posted January 21, 2021 1 hour ago, the_r_sole said: redesign a building to use less insulation There is, surface area to floor area is one metric, terraced housing is another. Orientation and wind shielding are others. I think forum members are biased in what they build. Is anyone here building a semi? Link to comment Share on other sites More sharing options...
MikeGrahamT21 Posted January 21, 2021 Share Posted January 21, 2021 District heating is a good option, but to be honest so is the gas grid...I know theres been a lot of negativity about gas, and natural gas does need to reduce, but as we use ever more hydrogen in the network, and also synthesis gas generated as a by product from waste etc, the gas grid will become far more efficient and low carbon than electric will be for a long time Link to comment Share on other sites More sharing options...
ProDave Posted January 21, 2021 Share Posted January 21, 2021 4 minutes ago, Iceverge said: Hello, yes Flat 1205, 12th floor, can you come and service my air source heat pump please? 1 Link to comment Share on other sites More sharing options...
Ferdinand Posted January 21, 2021 Share Posted January 21, 2021 5 minutes ago, Mr Punter said: Over half our housing stock is flats. A quarter is terraced houses. Most of it is existing. How the hell will the heat pumps work out? Recognise the issue, however afaik the actual % of flats in UK is more like 20-25% (6 million from 30 million ish). https://files.bregroup.com/bretrust/The-Housing-Stock-of-the-United-Kingdom_Report_BRE-Trust.pdf Fig 2.4. 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted January 21, 2021 Share Posted January 21, 2021 3 minutes ago, Ferdinand said: Recognise the issue, however afaik the actual % of flats in UK is more like 20-25% (6 million from 30 million ish). I wonder how many are converted houses? Not all flats are high rise. They are probably diminishing in number. 1 Link to comment Share on other sites More sharing options...
the_r_sole Posted January 21, 2021 Share Posted January 21, 2021 (edited) 1 hour ago, Ferdinand said: This is the comparison table with past and future regs @the_r_sole. Plus doc attached. Where do you think the extra cost is? I'm not really talking about the type of houses that people on here are building as most use the regs uvalues as the backstop, most housing providers use them as a target - a 5% increase on the cost of construction will more than double by the time it gets to buyers... rigid insulation prices have been increasing a lot over the last couple of years, the last note I had from a supplier here was there was a 17% increase between december and january, so requiring more insulation compounds price increases. Doors going from 1.4 to 1.0 in the short term is going to knock a lot of suppliers out as will the windows to 0.8 - I recently had an english window supplier tell me they were unable to produce whole window uvalue calcs!! Most of the houses we do already have heat pump heating and UFH but it's certainly not the norm on the developer led housing - if you've ever done a development appraisal for anywhere outside of the south of england you can appreciate the economics that even adding small costs can make projects unfundable... All these things have incremental costs associated with them, but it adds up very quickly over the entire construction. There should be a set target for new dwellings, even with something as blunt as SAP, which would allow the whole design, siting and construction to be accounted for rather than specifying individual elements for improvement. And just to be clear - I'm very much a fan of low energy/fabric first approaches! Edited January 21, 2021 by the_r_sole 1 Link to comment Share on other sites More sharing options...
Ferdinand Posted January 21, 2021 Share Posted January 21, 2021 One other elephant in this room is that even if implemented now there would be at least 5 years (more likely 8-9 ) before it made it into a significant proportion of houses being built. The housing estate I obtained Outline PP for in 2012/13 on family land has started to be built in summer 2020 ... and it's not a very big one by developer standards. 1 1 Link to comment Share on other sites More sharing options...
Iceverge Posted January 21, 2021 Share Posted January 21, 2021 No mention of form factor. You can build a super low energy demand house to current insulation levels if you keep the design compact. The window target is also some low hanging fruit. A neighbour priced upgrading to triple glazing on his 250m2 new build. €800 inc vat. 1 Link to comment Share on other sites More sharing options...
tonyshouse Posted January 21, 2021 Share Posted January 21, 2021 Why did this thread go dormant? Link to comment Share on other sites More sharing options...
Ferdinand Posted January 22, 2021 Share Posted January 22, 2021 We were missing you. x Link to comment Share on other sites More sharing options...
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