Buying a new house - heating options

Smiley_Dan

50mm is not anywhere near enough. Even with aircrete you're talking at best building regs standard. Try more like 200mm.

Furts

Smiley_Dan wrote: »

50mm is not anywhere near enough. Even with aircrete you're talking at best building regs standard. Try more like 200mm.

We cannot change what is already present, so the aim can only be to improve what is there. In the case of my home the build is 30 years old, and comprises 125mm aircrete, 50mm bead filled CWI, and facebrickwork which is well jointed and pointed, and sealed at the tops and everywhere else.

Hence the brickwork is acting like a jacket on the CWI.

All window and door openings are well sealed, all joist and floor areas are well sealed, so the end result is a warm house with low energy bills. Hence no need for 200mm!

Smiley_Dan

Depends what you want to achieve I suppose... and also a few other things wrt the house.

Going back to my original suggestion of no heating, you won't achieve that with U=0.3is (and then there's everything else to consider).

alarge

It was built circa 1950's so from what I have read it should have a 50mm(ish) cavity. The EPC certificate was done in 2014 (grade F).

Recommendations to get to a C grade would need an additional 270mm of roof insulation, CWI and floor insulation, hot water cylinder insulation. Solar PV and hot water as well as a wind turbine! It does mention that we could add external insulation as well as the CWI.

As a minimum I am looking to do the first three. Dare say the windows might need a good sealing. Would it be worth doing internal insulation? I have seen celotex backed plasterboard in varying thicknesses. Does seem like it may be expensive, would it take a while to pay back? I know it would reduced room sizes a little. Would the party wall have a cavity, I realise I would need consent from neighbours to do anything like that, so perhaps i could just internal insulation on that wall. Would also help sound proofing perhaps too.

macman

What's wrong with NSH's and an immersion heater running on E7? That should cost you little more than mains gas CH and DHW. Both oil and LPG will be more expensive to run, let alone the install cost, which you will never recover.

tonyh66

NSHs are a nightmare in the winter if you are out all day and come in there is very little stored heat in them. Had them in 2 houses and changed them both times.

Furts

macman wrote: »

What's wrong with NSH's and an immersion heater running on E7? That should cost you little more than mains gas CH and DHW. Both oil and LPG will be more expensive to run, let alone the install cost, which you will never recover.

I agree and my comments earlier mentionned E7 costing little more than gas.

Equally oil and lpg will not be cheap in perhaps a year or twos time.

Furts

tonyh66 wrote: »

NSHs are a nightmare in the winter if you are out all day and come in there is very little stored heat in them. Had them in 2 houses and changed them both times.

This runs counter to logic. Fabric first is the rule with insulation. If this is undertaken, and thinking of a typical cavity wall house, there will not be heat losses in the day, and there will not be the need for the boost in the evening.