God is in the Details

Great write up!

As discussed here too, for our house today vs with the planned EnerPHit, the difference is over £3000 reduction if done after renovation. (double that for GSHP). This trick feels "dodgy" but a few installers have indicated it's part of the intended model to encourage ppl to improve insulation and feel good about it as they're 'beating the system'.

 

Some gotchas:

- you need to first do the minimal improvements (if any) required by the current EPC, even if that is "throw away work" (e.g. installing loft insulation prior to converting loft...)

- doing afore mentioned temporary improvements will require a new EPC to be done, and the RHI likely reduced based on that improvement

- the payments will stop while house is unoccupied while renovating (and I assume those payments "lost")

- if unoccupied for >6 months the ASHP will need to be metered and payments reduced (as based on actual improved usage rather than old-EPC guesstimates)

- if the heating system gets "changed" in the renovation, ofgem need notified and potentially affects the payments (not clear what constitutes a "change" here. Moving pipes? changing rads to UFH? etc..)

 

To get around the "unoccupancy" and "changes" snags, my <redacted to protect the innocent>  had the great idea of getting the poor-performing (but no work required) EPC issued just before the renovation, but don't install the ASHP yet. Instead, do the full renovation, install ASHP, apply for RHI but use the EPC from before the works. An EPC is valid for 2 years, and nothing in the RHI seems to require it reflects the "current state" of the home, just done at some point in the last 2 years.

 

If we do go down the ASHP route (purely for Co2 reduction, not economic, reasons) and happen to be using a MSC installer anyway (e.g. they also do our PV) then we might as well do this. Just requires us to get that extra loft insulation put in now, and respin the EPC.

 

 

Edited to remove the penultimate paragraph. Not sure if it's been recently updated, but the RHI guide does specifically state the EPC needs to be a true representation of the state of the house when the ASHP is commissioned:  

"Your EPC must include a heat demand figure and must be less than 24 months old at the date of application. Your EPC needs to accurately reflect information about your house, so if you have undertaken construction work on your property you may need to get a new EPC to ensure it reflects your circumstances."

In our case, the renovation includes changing the floor area so a fairly clear case that it would need a new EPC issued.

Just comes back to the fact this whole incentive is broken: someone spending money to fundamentally decrease the energy used in their (non-renewable heated) property should get just as much (or more!) subsidy as someone switching energy source in a crap building.

 

 

Edited October 24, 2019 by joth

Thanks.

 

Good comments.