What are retrofit options for someone with 90-100m² ‘hard to treat’ home, concerned about rising gas prices and the planet? Installing a heat pump is single largest measure for lowering the carbon footprint, but how soon to fit one on retrofit journey? #retrofit #heatpumps 1/
Doing nothing on fabric or gas means bills will escalate
and there is a serious risk that such a home will have lower resale value in the future. By starting to think about retrofit, home owners might do things they have put off for years, like clearing the loft. /2
Getting off gas early prioritises planet, without bills needing to rise.
Install ASHP early alongside
Limited fabric measures, such as loft insulation to modern std; seals / brushes for doors / sash windows for drafts (and cavity wall insulation added if applicable) 3/
Further pragmatic fabric measures lower heat demand and bills
Install slightly cheaper ASHP alongside
Pragmatic window measures and for one or two rooms, additional measures for cold walls or floors where possible and might add localised MVHR
4/
More fabric measures reduce bills, but can delay getting off gas
Install ASHP late after
Extensive and often disruptive retrofit measures to many rooms, including Double or triple glazed new windows throughout and Insulation for some floors and walls & extensive MVHR. 5/
Further fabric measures very difficult to justify
Install ASHP very late
Extensive/disruptive project such as (often inapplicable to older houses)
Removing problematic fabric & replacing with energy efficient materials for walls, floors and windows. External cladding etc. 6/
For those wanting to get off gas and do pragmatic retrofit, so the bills stay about the same, then options B or C are best. Striving for deep retrofit will take years for most householders and is not without risks because fabric skills very difficult to scale-up 7/
I would argue, scaling up a heat pump industry is far easier than a PAS2035/PAS2030 compliant fabric industry.
Too often the fabric measures are discussed without the practicalities associated with disruption, and cost. 7/7
On the 'without bills needing to rise' (after fitting ASHP) - this may surprise many who have succumbed to the many myths around heat pumps (and esp. ASHPs) - here is the explanation of why …
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