Posted By: WillInAberdeenThe heat pump and PV and passivhaus people are angry because the "heat loss" metric doesn't reward renewable heat or passive gains, compared to fossil heat.

Do you have some links for those statements please? After a quick read of some of the consultation document those concerns appear to be misplaced, so I'd like to understand them more and perhaps comment to those who are angry unless I am convinced I have misunderstood the consultation.

Specifically as to 'the heat pump' people's stated concerns, the 'heat loss' metric doesn't say anything about the type of heating and so can't reward a particular type of heating or penalise one either. That reward will come out in the cost and/or the 'net-zero' compliant metrics, I think.

As to the PH people, I don't understand their concern at all, since the 'heat loss' is stated in terms of the heat supplied - "The energy required to be supplied by the heating system to achieve standardised internal conditions" - and this is affected by passive gains. (as long as it is calculated by some method such as PHPP which accounts for them, or is measured directly in the real house). Indeed it is very close to the primary metric used by PHPP, so I don't understand why they would be upset.

As I asked, do you have links, please? I'd rather read the original objections.

And no, I am not thinking about Building Standards regs.

It turns out that (like me) my professional contacts prefer not to have our work discussions posted on public sites. If you're in those circles then you know what people are saying; and if not then you won't have access to our links, though I can (and did) summarise for everyone.

Would also be good to keep on the substantive topic for at least the first few posts.

Here's a flavour of public discussion which is not always on point:

https://www.heraldscotland.com/news/23670366.gas-boilers-set-penalised-energy-efficiency-overhaul/

https://www.edinburghnews.scotsman.com/news/opinion/columnists/patrick-harvies-heat-pump-plans-are-nothing-more-than-hot-air-susan-dalgety-4235754


A more considered view is from the CCC who recommended that EPCs be based firstly on 'energy use' and then on 'fabric space heating', 'heating system type' and 'cost'. The first would recognise improvements such as heat pumps and PV that reduce energy use from public supplies, the second would reflect 'inspectable' insulation such as in lofts (although insulation buried in walls and floors is not inspectable for rdSAP).
https://www.theccc.org.uk/publication/letter-reform-of-domestic-epc-rating-metrics-to-patrick-harvie-msp/

For reasons unclear, the recent Scot gov proposal includes only the last three measures, so will not recognise heat pumps or PV as ways to meet the EPC C energy target. This is a change from recent policy, such as newbuild standards and retrofit grant schemes.

On this basis, BRE found that 65% of the housing stock are physically capable of meeting EPC C if they have inspectable wall, underfloor and roof insulation added, the rest will not (so will not be let-able and later not saleable).They didn't say how the insulation under slab floors is going to be inspected!

Virtually no homes will get to EPC B under rdSAP 2012, only newbuilds on their first 5-year EPC (for which full SAP can be used). So PHs will drop to EPC C after that time.
https://www.gov.scot/publications/bre-client-report-development-work-relating-potential-new-metric-scottish-energy-performance-certificates/

Worth also understanding the political context in Scotland where the SNP do not quite have a parliamentary majority and govern together with the Greens. The Greens have used this influence to launch very ambitious/idealistic reforms (DRS and others) which the SNP subsequently backed away from when the impracticalities became clear, blaming their junior partners and/or England. Maybe the same here.

ETA: the 'commonweal' proposal is to use last year's energy bills to award the EPC - the practical problems with this have been well discussed.

Hmm, unsupported opinions - the very stuff of rational debate. I do understand your colleagues' reluctance to stand up and be counted, it's all too common, but it doesn't help the uselessness of posting random opinions and ascribing them to whole groups of people.

I'm not sure what you think the 'substantive topic' is or what your opinion or goal is.

Having a proper fabric efficiency measure as a primary measure sounds sensible to me. Then having separate measures for heating system type and for renewable energy generation etc also sounds sensible.

There are lots of details that I could comment on but shan't at this stage. The biggest practical problem may be the need for twice as many EPC assessors if they shift to 5 year validity, as well as retraining them all to the new system.

Posted By: WillInAberdeenVirtually no homes will get to EPC B under rdSAP 2012, only newbuilds on their first 5-year EPC (for which full SAP can be used). So PHs will drop to EPC C after that time.

My PH got EPC C when assessed under SAP when it was built. (SAP *must* be used for a newbuild) So there's no question of it 'dropping' to C Typically higher rated houses seem to have a lot of renewables. I'm not sure there's much value in that.

I wonder what percentage of certain GBF users' posts have been "useless unsubstantiated opinions" this week. I could go through their posts and point out their lack of "evidence", starting with this thread. But that would be tiresome, and perhaps a little rude, so I shan't :-)

"EPC rating is likely to drop even though nothing has changed!" "What a barking system" - yes indeed. This proposal is still open for consultations, link in the OP.

Seems to me that an off-grid renewable-powered property with zero emissions and zero energy bills, should get EPC A, and other properties should get proportionately worse. But under this proposal, that property could get a poor EPC, based on its year of build in rdSAP.

Does this mean if reassessed, my EPC rating is likely to drop even though nothing has changed!

Already happens.

I built a block of 4 small flats in 2004 with the intention of renting , the first EPC came in at B’s all round , 10 years later they were all assessed as being very average C’s, with the varying news on energy efficiency and possible changes to the assessment i decided to lock in the C’s for 10 years in view of them all having had new gas boilers , uprated heating controls and ensured Led lights everywhere. So had the epc’s done again this year , 5 years early.
Now all good C’s not far from B’s but no practical/economic way to make the jump.

Hopefully in ten years there’ll be a coherent and stable set of rules and regs , along with a mature well supported industry revolving around what is eventually deemed the correct path to follow. Though it looks as though the proposals around energy efficiency standards in the rented sector have been kicked well into long and fast growing grass. If gas is to be less advantageous under any new assessment procedure huge swathes of the current private rented sector will be made unviable as a business or totally unaffordable to tenants if the work is to have any sensible payback period. Being unable or unwilling to meet any new standard must surely be grounds for gaining possession of a property to enable it to be sold, the mess the private rented sector is getting into as overall stock is being reduced has likely woken a few in the corridors of power to the consequences of endless meddling.
Fortunately scotland has decided to test the water first.

>>>> "81kWh/sqm per annum for space heating and 2,000kWh per annum for hot water. (GSHP for both)
apparently 2.5kW of PV would get me to an A (94)"

That sounds excellent to me, but the proposed Scottish system will not give credit for the GSHP or PV, or for renewable hot water.

The threshold for EPC C will be set at 71kWh/m² of space heating in rdSAP irrespective of the heat source (ref BRE link above), so Dominic's house would be downgraded from present EPC B, to a D or worse under the new system.


>>>>>"Is it likely that there will be exemptions for loads of properties...such as listed buildings,conservation areas"

No exemptions in these proposed regs, about how EPCs are allocated in Scotland.

There will be separate regs this winter for the "it must be EPC C to be rented or sold" bit. Presumably there will have to be exemptions as only 65% of housing can technically be upgraded to EPC C without giving credit for heat pumps or PV, and there will also be non-technical reasons such as LB/CA. The minister has been putting a positive spin, that this means "the majority" of properties can/will comply.

Seeing these figures here thought would present my figures.
In 2021 our 1st full year used 3266 kWh of propane gas
and about 4000kWh of logs difficult to quantify as do not know the weight.
Used 3099 kwh of electricity" the total load " but only 811 came from grid rest was solar.
Hot water do not have a clue as most came from solar thermal and some from the heating propane.
In total we used 10365 kWh House is 340 sqM so 30.5 kWh/sqM.
Costing distorted by the subsidies last year but we only "paid" for the propane and grid electricity, logs came of our land as fallen branches and we got a good price for our export of electricity which totalled 3324.6 kWh at variable rate. So with that and fuel payment worked out well we were net surplus £.
Where would be on the EPC scale goodness knows hope and it would be good, though it would be an academic point.

Posted By: ArtiglioTotal gas use 4331 M3
Total electricity use 25172 kwh

I presume that was over the 18 years. The gas converts to 139269 kWh I think. So a total of 9136 kWh/year and 277 kWh/m²/a which seems rather high with a decent EPC but maybe small properties use more proportionately?

AIUI the present EPC numbers include hot water, cooking and lighting, and losses due to boilers being less than 100% efficient. The proposed Scottish 71kWh/m² cutoff for an EPC C will exclude those and only include space heating output, so I think Artiglio's 83 kWh/m² flat would still qualify.

EPCs reward those properties with efficient shapes (such as flats with few external walls), unlike newbuild SAP calcs for Building Standards/Regs.

Posted By: ArtiglioI’ve another longterm tenant in a mid floor 2 bed flat, i’ve asked if they have any details on energy use i could look at, they said yes but will be amazed if they actually pass anything on,

Don't you keep tabs on the utility bills to see that they are paid. Over here debts run up to utility companies can and are attached to the property so a land lord can suddenly get a nasty surprise.

PIH, no here it’s down to the last account holder to close their account , the utility companies then charge the landlord for the void period and the landlord informs the utility of the new tenant, so long as that is done it’s all down to the tenant and forms part of the tenancy agreement. But these days of automation means that actually closing an account , opening a new one , closing that and opening another over the course of 2-3 weeks is beyond the suppliers most times and their systems go haywire. So I read the meters when a tenant leaves and they agree the figure and that’s what the account is closed on. Ignore the welcome letters addressed to the “occupier” then get new tenant to take over from the last tenants readings and i pay the new tenant the difference upto their move in read. Not how it should be done but by far the most efficient.
All gets complicated with prepayment meters especially if the previous tenant has run up a debt and walked away. That can get really difficult mainly because you just can’t talk to a human and all the data protection rules. In my pther block the number of debt collection letters that arrive is incredible and some refer to tenants that left 15 years ago. I’ve a tenant that left 2 years ago and obviosly owes money to hmrc, about 5 letters a week come for that person. I used to put “no longer at this address , return to sender” and stick them back in post, but it’s a pointless exercise that does nothing. Now they just get binned.
You always know when a departing tenant has left a trail of debt, they have terrible trouble remembering their new address, so i just ask them to put “ forwarding address declined” on the check out form and sign next to it. Then if any entity gets the hump i email a copy to them along with the date they left.
The tenant that has just left, took me for £1300, made no effort to clean anything , now has the gold medal for the filthiest toilet i’ve been left with ( a gallon of acid so far and its still a bubbling cauldron of filth), had left by the yime i arrived for the checkout and no forwarding address, so there’ll be a few outstanding bills for them. But being benefit dependant and no assets they can pretty much do as they wish , the evil wicked landlord would be expected to bear the loss by the courts so a waste of time and money chasing them. But it’s the last benefit tenant i’ll ever take on. The change in attitudes in the 25 years i’ve been renting is quite staggering.

https://think.ing.com/articles/review-of-the-energy-performance-of-buildings-directive-major-renovations-ahead

In the EU, it looks like all EPCs will be re-graded, so that they use the same scale in all member states.

The new scale will be from A for a zero-energy building, through to G for the worst 15% of buildings. There may be an A+ for buildings that export energy.

Unlike in Scotland, it will be based on Primary energy use rather than on fabric heat losses. So adding a heat pump should improve the EPC in the EU. There are drawbacks to measuring 'primary' rather than actual energy use or CO2 though.

There will be targets that housing has to improve to EPC E and then D by certain dates, and to add solar.

They will introduce a lifecycle GWP measure to discourage high-carbon construction materials.