PAS 2035 is the UK's standard for home energy retrofits. If you're considering improvements or applying for grants, here's what the standard involves and why it matters.
PAS 2035 is the publicly available specification that sets the standard for domestic retrofit work in the UK. It was introduced in 2019 to improve the quality of energy efficiency work following concerns about poorly designed retrofits causing damp, condensation, and structural problems.
PAS 2035 defines several key roles: the Retrofit Assessor, who surveys the property and produces the Improvement Measures Report; the Retrofit Coordinator, who manages the improvement process; and the installer, who carries out the physical work. At Carn Energy, our ABBE-accredited assessors are qualified to carry out the Retrofit Assessment stage.
The assessment covers the building fabric (walls, roof, floor, windows, and doors), the existing heating and hot water systems, ventilation, and occupant wellbeing considerations. The output is an Improvement Measures Report that prioritises improvements and ensures they work together safely as a system, rather than individual measures that could cause problems in combination.
PAS 2035 emphasises a 'fabric first' approach , improving insulation and draught-proofing before upgrading heating systems. Adding a heat pump to a poorly insulated home, for example, would be inefficient and potentially costly. The Retrofit Assessment ensures improvements are planned in the right sequence.
You need a Retrofit Assessment when accessing government grant schemes such as ECO4 or the Great British Insulation Scheme, or when undertaking a coordinated programme of improvements rather than isolated measures.
ABBE-accredited, TrustMark-registered PAS 2035 Retrofit Assessments across Lambeth, Wandsworth, and Southwark.
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ABBE-accredited EPC assessments across Lambeth, Wandsworth, and Southwark.
