Green Building Forum - Retrofit underfloor insulation - EPC

Retrofit underfloor insulation - EPC

Osprey — Thu, 11 May 2023 12:39:14 +0100

Has anybody managed to get DIY underfloor insulation (wooden, suspended floor) recognised for EPC purposes?

I cannot find any company even willing to quote for the work (except for spray foam). Even the company the local authority use for grant-funded insulation work will not do it, and suggest DIY is the way to go.

Retrofit underfloor insulation - EPC

WillInAberdeen — Thu, 11 May 2023 12:52:10 +0100

We had an EPC and the assessor would only credit insulation which he could see, measure and photograph; or else if there was a certificate he could photograph from an official body such as building control or FENSA. He had to send off the photos to his accreditation body.

He would only credit our DIY underfloor insulation if we lifted some floorboards, so that he could see/measure/photo the insulation thickness. However he only had 30minutes on site to do the whole house EPC so we didn't have time, if we'd known in advance we could have lifted boards ready for him. He would not accept photos or receipts I had kept from when I installed the wool. We were not that bothered anyway.

So the resulting EPC has a spurious recommendation to 'add underfloor insulation'.

To be fair the assessor gets paid peanuts, maybe you could do a deal with an assessor to spend longer on your house and do a better job.

Edit: DIY insulation under timber susp floors is messy but not too difficult and gives good improvement.

Retrofit underfloor insulation - EPC

Osprey — Thu, 11 May 2023 14:23:02 +0100

Thanks, Will. That's what I suspected: not really practical to wait on an assessor when DIY over a weekend. Maybe the LA will realise the problem and be a bit more lenient, if they want us to insulate.

I have already done one room (100mm PIR) and made a hatch which I can lift if needed. Still need to roll back a fitted carpet, which I would prefer not to do.

Retrofit underfloor insulation - EPC

Nick Parsons — Fri, 12 May 2023 12:20:35 +0100

Hi Osprey,

You say ''Maybe the LA will realise the problem and be a bit more lenient, if they want us to insulate''.

Except for compliance with Bldg Regs, where do the LA come into it? Is it a rented property? I am not sure when (other than with rented properties, though I don't even know who 'polices' EPC stipulations - I assume it's the LA) LA and EPCs 'interact', certainly for owner-occupiers.

Subject to what others have said re access/evidence, there is AFAIK no requirement that it has to be done by a contractor , I think. It just has to be able to be seen. 'How much of it?' is an open question. OTOH an EPC assessor did not 'see' insulation which I think any of us would have seen, or at least suspected and asked further Qs. It really is such a shame that the system was designed to be so cheap that it is almost bound to be 'unsatisfactory'. There is also a huge range of skills out there too. I can think of ones who I'd be quite happy to do an energy survey of my house, provided it was not within the tight constraints of RD SAP.

Retrofit underfloor insulation - EPC

Osprey — Thu, 15 Jun 2023 19:57:48 +0100

Posted By: Nick ParsonsHi Osprey,

You say ''Maybe the LA will realise the problem and be a bit more lenient, if they want us to insulate''.

Except for compliance with Bldg Regs, where do the LA come into it? Is it a rented property? I am not sure when (other than with rented properties, though I don't even know who 'polices' EPC stipulations - I assume it's the LA) LA and EPCs 'interact', certainly for owner-occupiers.

Subject to what others have said re access/evidence, there is AFAIK no requirement that it has to be done by a contractor , I think. It just has to be able to be seen. 'How much of it?' is an open question. OTOH an EPC assessor did not 'see' insulation which I think any of us would have seen, or at least suspected and asked further Qs. It really is such a shame that the system was designed to be so cheap that it is almost bound to be 'unsatisfactory'. There is also a huge range of skills out there too. I can think of ones who I'd be quite happy to do an energy survey of my house, provided it was not within the tight constraints of RD SAP.

Sorry, just sent your comment. LA (Bld Regs) will look at what your doing for UF insulation, and, if happy, issue a certificate saying OK. For Â£300. This can be given to EPC inspector as proof.

Reason to involve LA is to get higher EPC, which I think will have significant effect on future sale price..

Retrofit underfloor insulation - EPC

Nick Parsons — Fri, 16 Jun 2023 14:01:50 +0100

A completion cert does no harm, and I spend a lot of my working life trying to encourage people to comply with Bldg Regs. However I am not convinced (though happy for others to gainsay me) that in the case of an EPC a BC cert will (as you put it above) 'get (a) higher EPC'.

If what you mean is that you will have it all 'boxed up' and no longer accessible then yes, but if you can have an access hatch then all the EPC assessor (AIUI) has to do is be able to measure the depth of insulation and to photograph it. Then they tick the relevant 'box' in the s/ware. BC-approved or not, the answer should be the same, but BC-approved is always better in my view because (a) it's what you are supposed to do and (b) you can scare off potential future purchasers who are trying to drive down the asking price because they think you have done work without BC approval (at which point you whisk out the cert....)

Retrofit underfloor insulation - EPC

Osprey — Sun, 18 Jun 2023 16:54:09 +0100

Posted By: Nick ParsonsA completion cert does no harm, and I spend a lot of my working life trying to encourage people to comply with Bldg Regs. However I am not convinced (though happy for others to gainsay me) that in the case of an EPC a BC cert will (as you put it above) 'get (a) higher EPC'.

If what you mean is that you will have it all 'boxed up' and no longer accessible then yes, but if you can have an access hatch then all the EPC assessor (AIUI) has to do is be able to measure the depth of insulation and to photograph it. Then they tick the relevant 'box' in the s/ware. BC-approved or not, the answer should be the same, but BC-approved is always better in my view because (a) it's what you are supposed to do and (b) you can scare off potential future purchasers who are trying to drive down the asking price because they think you have done work without BC approval (at which point you whisk out the cert....)

I have read several posts on various sites where the EPC person would not accept photos or various other evidence of UF insulation. Even with an inspection hatch (hatches for multiple rooms) it is not trivial to lift fitted carpets or other flooring for them to look and measure.

So, BC route if possible. So far, BC seem to have been quite helpful and understanding of getting approval, on this sort of DIY project. Hopefully it will continue when I get down to it.

Retrofit underfloor insulation - EPC

Nick Parsons — Tue, 20 Jun 2023 16:51:42 +0100

With regard to the fee for signing off 'Renovation of a Thermal Element' it is worth pointing out that fees vary by area. Where I live it is Â£180, where other local-ish Authorities charge Â£250 and Osprey refers to Â£300.