What sort of running costs do you have and what are the maintenance costs. Please exclude any solar panel subsidy from the calcs. What sort of property and insulation etc. Real world info helps people make informed pragmatic choices. Any investment has to be done open eyed and informed so your info and that of others would be helpful in this regard
It costs me £200 a year for a service but once our if warranty it is hardly worth it.
How are you achieving the insulation on your solid walls ?
Downstairs is a foot thick so don't need it. Upstairs is partly double brick with no cavity. Used internal insulated plasterboard where necessary. A large section is cladding with insulation.
I can’t comment on living with an ASHP, but am going through the process of getting one.
That 750 sounds very low, is there some other factor ? The insulation details for all these installations would I believe prove helpful
Based on using Octopus cosy, 120sq metre property, small part modern extension, rest as above, EPC E.
I agree with Penninetrader that does sound extremely low for a house of that size. I am surprised your getting 400% out of a house with a EPC of E.
My electricity use is approx 5500kwh
That sounds pretty good, I suppose the devil is in the detail, average Temps and the hours heated plus hot water consumption etc. What surprises me is the low D rating for a quite well insulated property with PV and a heat pump.
It will be interesting to see how it goes in the real world
Yes the D rating was a surprise to me but I think the assessor was a bit of a w****r as he seems to have forgotten the floor insulation and the PV was added later.
For some reason, when doing an EPC for an existing property, floor insulation does not appear to affect the score. In any case, it is usually very difficult for an assessor to find sufficient evidence that the insulation is present.
With an ASHP, the hot water temperature for showering, washing and bathing is very controllable and although it needs to use an immersion element to top up the temperature, the temperature is usually set to between 50 and 55C; it does not have to be at the same temperature as the radiators or underfloor pipework. It can be set to boost that to 60C+ for about half an hour every four to six weeks to kill off Legionella bacteria.
This was what it looked like when he did his assessment and you can see the insulation at the edges!
Prattling off the top of my head, the underfloor is the key imo due to the low flow temp required to feel comfortable, insulation as for any system is high on the list, balanced heat throughout creates pressure outwards, that contributes to less air movement and again a feeling of comfort, a pretty airtight home, not ridiculously so. The foregoing leaves an unhealthy house of stale air so in combination a simple heat exchanger to import fresh air will do the job and also not unduly affect the pressurising. All of this would make any form of heating more efficient. IMO, the ASHP should be the last on that shopping list unless you can afford to do it all. Insulation and a wooly jumper costs nothing further after purchase, yes ok you have to wash the wooly jumper.
In that regard the assessment becomes an absolute nonsense, floor insulation is as important as roof insulation in regards heat loss, A photo record of the floor installation and any related work should suffice.Most of this EPC rating work seems to be quite the sham
That looks a very neat job, very tidy masking off for the screed.
