Insulating and electrifying our house

Our house will stop burning gas by the end of 2024.

Year	Gas consumption (kWh)
2021	5,157
2022	3,180
2023*	2,865	↑ 25%

*2023 consumption from 1st January to 17th October 2023. Comparison is for the same period in 2022.

Roadmap

In November 2022 we had a Retrofit Assessment from People Powered Retrofit. This gave us a great roadmap to a fossil-fuel-free house. It also alerted us to big problems with our ventilation and air quality.

We’ve chosen to improve these areas:

• Ventilation - in progress
• Loft - autumn 2023
• Windows - autumn/winter 2023
• Walls - autumn/winter 2023
• Heat pump - spring 2024

Progress so far:

• Installed rooftop solar panels.
• Replaced front door.
• Insulated downstairs toilet.
• Electrified our hot water heating.
• Had a full home assessment by the excellent People Powered Retrofit.
• Replaced gas hobs with induction.
• Found and eliminated wasteful electricity usage.
• Sealed up various holes to improve airtightness

Next up, roughly:

• Replace loft hatch with air-tight model.
• Install mechanical ventilation to balance air-tightness efforts.
• Replace knackered uPVC windows with triple glazing with insulated reveals, cills & heads.
• Re-do loft boarding and install 350-400mm² mineral wool insulation.
• Replace roof soffits including wind diverters.
• Replace hot water tank with unvented type.
• Install ~4kW heat pump.

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Resources

• Centre for Alternative Technology (CAT) Free Information Service

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Progress log and notes

August 2023

• signed contract with People Powered Retrofit to make a Home Retrofit Plan
• sent window dimensions and layouts to Ecospheric for initial price
• cleared a load of wood from loft in prep for replacing boarding
• measured joists, trusses, loft hatch etc and modelled in Sketchup
• ordered air tight loft hatch (AT15) with U value 0.15 W/m²K
• received new loft hatch. measured and double checked dimensions.
• destroyed removed architrave from loft hatch
• Ordered 6mm thick timber to reduce the width of the loft hatch between joists. The new airtight loft hatch needs a very precise hole to mate with its foam seals.

September 2023

• Emailed:
  • Scandinavian Timber, - Very fast and conscientous reply.
  • West Port, - honest reply, they can’t achieve 0.9W / m²K
  • A&H Windows
• Installed timber strips into loft hatch, flush with ceiling plaster.
• Installed loft hatch into position. The ceiling needs fixing but the position and seal look good.
• Drew dMEV design onto floorplan
• Finished draft ventilation design, sent to People Powered Retrofit
• Ordered ventilation fans, acoustic ventilators, CO₂ sensors
• Emailed Retrofit Windows in Shrewsbury (suggested by Ecospheric as they offer supply and install)
• Pestered People Powered Retrofit to start the Home Retrofit Plan