standby electricity costs

Pincher

elantan wrote: »

We live in a poorly insulated ( that's a whole other thread ... But we've tried to feal with it honest ) detached bungalow with a half basement ( if you know what I mean )

I am in a semi-detached bungalow, and the insulation was truly appalling. It was totally refurbished twenty years ago, a few years before we bought it, but there was hardly ANY INSULATION. I have been doing major renovations in the last three years, and here are some thoughts.

It's not enough to do the work, but you have to show that you have done the work. I have buried acres of Kingspan in the roof, on the sides around the 1st floor living space, even the floor for underfloor heating reasons. We took down the internal plaster on some of the solid walls, and replaced them with thermal plaster. I spoke to an energy inspector, and he said he can't give me credit for any insulation that he cannot physically see. If I have photographs of the insulation before we sealed them in, or a certified insulation company's invoice, then he can give me a better rating on the Energy Performance Certificate.

If you haven't opened up the loft, laying loft insulation down is a piece of cake, and you can show that to an inspector any time. It's also where the heat escapes mostly in a house. With solid walls, the least disruptive approach is external thermal plaster, but you are looking at £15,000, approximately. You need to use a recognised company that can issue a certificate for the EPC inspector.

Internally, the window shelf is a limiting factor. Don't waste time trying to keep the window shelf, rip it out and get a deeper one. Yes, you will have to redo the coving too. The skirting board you can trim to fit.

On the budget end, there are plasterboards with polystyrene bonded to it, about 50mm thick. Screw it to the external wall, fit the new deeper window shelf, wall paper, job done. As polystyrene is not breathable, you will need to ventilate to get the moisture out, or use a dehumidifier. MVHR (Mechanical Ventilation eith Heat Recovery) is worth considering, every room in the ground floor is accessible from the loft. Note that the 50mm does not bring you maximum insulation recommended, but it gives good value for money and effort.

A better option is 40mm thick of internal thermal plaster. Because you remove the old plaster, about 20mm thick, it means you only lose 20mm in the length of the room. The thermal plaster is breathable, like normal plaster.

Forget about thermal paint and wallpaper. They are better than regular paint and paper, of course, but ultimately pointless.