AECB CarbonLite Retrofit standard
An achievable retrofit standard between baseline UK practice and full EnerPHit, with a library of monitored projects behind it.
Source
Summarised from Association for Environment Conscious Building, a Tier 2 source on Your Home Climate. We did not run this project; the figures below are reported by them. Click through to verify any of them at the original publication.
https://aecb.net/carbonlite/The problem
EnerPHit is the gold standard and out of reach for most owners. Building Regulations are the minimum. The gap in between, where most useful work happens, lacked a coherent standard until AECB published CarbonLite.
What they did
CarbonLite Retrofit defines achievable targets for fabric performance, airtightness and primary energy. The standard is supported by a network of trained professionals and a library of completed projects that demonstrate what each target feels like in a real UK home.
What the source reports
- CarbonLite Silver airtightness target≤ 3.0 ach @ n50measured
- CarbonLite Gold airtightness target≤ 1.5 ach @ n50measured
Measured means monitored data from the site. Reported is the publisher's stated figure. Modelled is a target or design figure rather than an outcome.
What we take from it
- An intermediate standard is more useful than a perfect one most homes will never reach.
- Airtightness targets are the most reliable single proxy for how a retrofit will actually perform.
What the source does not tell us
- Standards do not deliver projects. The presence of a trained designer and a competent installer still matters more than the certificate above the door.