Retrofit Assessment Vs EPCs

CityTiger

We moved into our property around a year ago. It's a rural property (circa 1850s) with solar panels and a solar boost water heating and an external boiler running on oil. It's about 50% solid walls and 50% cavity walls.

Last year we used around 2,300 litres of oil. At today's prices that's approaching £2,300 a year, plus electricity bills on top (approx £900 for past 12 months - but obviously that will rise significantly over the next 12 months).

We found that despite spending that much on oil, we were still cold in the property at times (perhaps as much our reluctance to put the heating on for too long as it was to do with the house itself, though two upper rooms did feel particularly cold despite good loft insulation).

As a result we want to look into the best options for improving our energy efficiency. The EPC of the property suggested internal or external wall insulation at a cost of £4,000-£14,000 for an expected saving of around £298 per year. However, that was based on assumptions about there being cavity wall insulation but no solid wall insulation. I assume the savings are also based on early 2021 energy prices too.

From what I understand, it may not be viable for us to have external wall insulation as there is very little overhang on our roof to accommodate the extra wall thickness, plus one of our walls forms the boundary to the neighbouring property, so I assume any addition to the thickness of the wall would technically encroach the boundary.

That then would leave us with the very disruptive option of internal insulation (I believe 6 rooms would need it). I'm not against this but it does obviously come with big disadvantages.

There was nothing on the EPC about installing a heat pump, though that does interest us a lot, partially because it has added benefits such as being able to remove the big oil tank taking up space in our garden!

Trying to work out our next best steps for finding out our best route forward. I'm trying to contact Retrofit assessors but so far haven't had any luck in finding one that covers our area and is willing to do take on the job. One outside of our area did recommend having a good EPC person round to redo the EPC with our plans in mind, but I'm concerned whether we might just end up paying for it just to give us virtually the same as what we already have.

The other option, I guess is to get quotes for both a heat pump and internal insulation and see if we can figure out the best route from there. It's highly unlikely we can afford to get both done but we want to be sure we invest in something that will make us feel a difference proportionate to our expenditure.

Any suggestions or advice greatly appreciated.

Reed_Richards

EPCs have a blind spot about heat pumps; you will never find them recommended and as things stand at present they will reduce your EPC score (this should change soon).  However with a heat pump, properly installed but running radiators, you might reasonably aspire to get about 3 kWh of heat per kWh of electricity used.  If you do the maths that will not offer you a huge saving over running your oil boiler, provided that it can achieve modern levels of efficiency.  

JohnRV8

... The EPC of the property suggested internal or external wall insulation at a cost of £4,000-£14,000 for an expected saving of around £298 per year. .... I assume the savings are also based on early 2021 energy prices too.

Don't assume its based on 2021 figures, my new 2022 EPC is no different from my 2012 EPC showing 4.3p/kWh for gas whereas its now 7.3p/kWh. Somewhere on your EPC it should say the kWh of oil saved by adding insulation.