Grade II listed building on track for Enerphit after airtightness retrofit

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Central Lodge had already undergone significant renovation as part of a wider Enerphit retrofit led by Lancashire Heritage Ltd, with Progress in Practice advising on the project. Aeroseal UK was brought in to address residual air leakage using its AeroBarrier system, which disperses an airborne sealant to fill gaps in the building envelope.

The process reduced airtightness from 3.05 air changes per hour at 50 pascals to 0.87, comfortably below the Enerphit limit of 1.0. The seal took three hours and twenty minutes, with the reduction in leakage shown in real time.

The challenge on a listed building is to improve performance without damaging heritage fabric. AeroBarrier works by pressurising the building and releasing a fine aerosol that is carried to leakage points, sealing gaps without the need for intrusive manual work.

“One of the big challenges with airtightness on retrofit is sequencing,” said Hannah Dixon, architect and director at Progress in Practice. “Using AeroBarrier on this project allowed us to de-risk the airtightness much earlier than would otherwise have been possible. This then unlocked progress with subsequent trades and packages, shortening the programme and saving cost.”

“This project demonstrates what is possible within historic buildings,” said Lancashire Heritage Ltd. “Aeroseal UK’s contribution has been invaluable.”

Central Lodge sits on the fringe of Birkenhead Park, which opened in 1847 and is thought to be the world’s first publicly funded municipal park.