Exterior wall insulation improvement u 0.8 to 0.3 - Insulation job in Kingston Upon Thames, Surrey

  • Location
    Kingston Upon Thames
  • Trade
    Insulation
  • Posted
    3213 days ago by damonhd
  • Tradesmen
    4 interested

Job description

Hi,

We've done a lot of obvious things to our 1968 timber-frame end-of-terrace 3-bed house to more-or-less double heating efficiency over the last year or two and shrink our home carbon footprint considerably (maybe from 6tCO2/y to 2t/y):

http://www.earth.org.uk/towards-a-LZC-home.html#todo

and:

http://www.earth.org.uk/saving-electricity.html#meter

But what I *believe* we need to do next is improve the exterior walls from an estimated U-value of 0.8W/m^2/K (in part from the SAP tables and guessed plasterboard / small void / brick outer leaf) to better than current building regs, ie maybe 0.3 or less.

I *think* that this would be possible with a foil-based insulant insert in the void and a lining of something like Spacetherm aerogel inside without losing too much space. I think that would also allow enough air circulation to avoid rot in the structure.

What I'm *sure* I need is (a) grown-up advice and (b) a sensible localish contractor to do any install (I'm certainly not handy enough to attempt it myself). I thought I'd got both but everything went very quiet. B^>

I'm trying to cut 2MWh/y off hard-winter space-heating demand, from ~6MWh/y.

At some point I hope to save ~2MWh/y in gas DHW with solar thermal (in addition to our existing solar PV), and would expect to have to pay ~£4k for that. I'm prepared to pay pro-rata a similar amount for space-heating savings from insulation if needed, ie up to ~£2k/MWh/y saved for a job well done.

Rgds

Damon Hart-Davis