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@mike-patrick I can't help but feel you might do well to find another assessor. It seems there's too much room for interpretation and so a change of assessor might well elicit someone who can effectively get your EPC to say what you want. Not great, but we didn't make up the rules, eh?
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; sumus solum profundum variat"
@mike-patrick - click on 'document'
@ronin92 - clearly whoever is in charge at the BRE and tasked with preparing the SAP methodology for heat pump efficiency has a pathological hatred of them. Perhaps they were employed by one of the big ASHP manufacturers before being sacked for incompetence.
There appears to an outbreak of incompetence these days, in fact it is reaching pandemic level. 🙄Â
Â
i refurbished a property in 2015 with major works that included
- new insulated roof (under building regs)
- cavity insulation in the extension
- internal insulation on solid walls behind plasterboardÂ
- new windows & doors
- panel heaters with timers & thermostats
Unfortunately did not get epc at the time (as no need) when I got it done last year it came up with laughable E
lots of wrong assumptions they were unwilling to change
to cut a long story short after a battle it was finally revised to take account of most of the changes. BUT
Internal insulation was disregarded as Thermawrap type has no category in EPC despite usefulness.
Finally only additional change i made was installed a "High Heat Retention" storage heater at ridiculous cost £600+ even though it remains extremely doubtful it will save any money and tenant has no intention to use it.
Upshot was a C ratingÂ
The system is unfit for purpose
Â
Â
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
Posted by: @tim441i refurbished a property in 2015 with major works that included
- new insulated roof (under building regs)
- cavity insulation in the extension
- internal insulation on solid walls behind plasterboardÂ
- new windows & doors
- panel heaters with timers & thermostatsUnfortunately did not get epc at the time (as no need) when I got it done last year it came up with laughable E
lots of wrong assumptions they were unwilling to change
to cut a long story short after a battle it was finally revised to take account of most of the changes. BUT
Internal insulation was disregarded as Thermawrap type has no category in EPC despite usefulness.
Finally only additional change i made was installed a "High Heat Retention" storage heater at ridiculous cost £600+ even though it remains extremely doubtful it will save any money and tenant has no intention to use it.Upshot was a C ratingÂ
The system is unfit for purpose
Â
Â
I presume it was an electric 'storage heater'?
How much do assessors get paid? Is it 'peanuts' by any chance?
Â
@derek-m yes, HHR storage heaters are electric. The ones acceptable for EPC purposes are a very narrow list - not all.
The manufacturers have to apply to be on the list and many have not bothered. No doubt in part because of cost & bureaucracy.
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
As a postscript I'd add that after completing renovations my EPC rating was initially E with the first assessor. He would not recognise the internal wall insulation we'd put in, because he could not personally check for its presence, even though I had plenty of photos of the installation work. I refused to pay for the inspection and went to another assessor. In a fortunate co-incidence he proved to be the assessor who had last seen the property before we bought and refurbished it (with a G rating). He did accept my evidence and we ended up with our current D rating. I see no way of improving on this until the EPC rating system is changed so it no longer penalises ASHPs.
Â
Mike
Grant Aerona HPID10 10kWh ASHP
@mike-patrick agreed. The system is not fit for purpose. As properties change hands the historical info on works completed is not going to be available to assessors or new owners in many cases.
somehow assessors will need to have a better way of accepting the evidence in a sensible way (tricky balance so the system is not abused?).
But also changes to accept ASHP and that panel heaters that have thermostats & timers are not evil! And case by case ways of refurbishment is not one size fits all.
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
Posted by: @tim441@mike-patrick agreed. The system is not fit for purpose. As properties change hands the historical info on works completed is not going to be available to assessors or new owners in many cases.
somehow assessors will need to have a better way of accepting the evidence in a sensible way (tricky balance so the system is not abused?).
But also changes to accept ASHP and that panel heaters that have thermostats & timers are not evil! And case by case ways of refurbishment is not one size fits all.
I suppose the simplest way to assess energy efficiency could be by annual energy consumption per square meter.
Â
@derek-m I like that idea as it's one number that everyone can understand. Hides a lot behind it but a useful heuristic.
Last year for mine (total energy use as ASHP not separately metered) was £70 per year per sq.m. Without others to compare I've no idea whether this is good, bad or typical. The only comparison I know of is my aged relative's house (80's built and well insulated). She uses almost 3x my annual kWh (28,000 KWh of gas and electricity). She can afford it but I've told her to use the coal-effect gas fire less and get a new thermostat for the hall as the existing one seems not to work.
Mike
Grant Aerona HPID10 10kWh ASHP
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