PAS to Passivhaus: Comparing Retrofit Standards
Introduction
As the UK moves toward its 2050 net zero target, retrofitting existing homes is a national priority. However, energy-efficient building – especially retrofit – carries risks. Poorly executed upgrades can lead to mould, condensation, and structural damage, affecting occupant health, comfort, and long-term durability. To address these risks, PAS 2035 provides a structured, risk-managed approach. It includes ventilation checks, moisture control, and post-installation evaluation, supported by whole-dwelling assessments that consider building condition, occupant behaviour, and measure interaction.
PAS 2035 operates within a wider compliance ecosystem, interacting with Building Regulations, British Standards, and other technical guidance. Within this landscape, Passivhaus and its retrofit counterpart EnerPHit offer a gold standard for performance and comfort. Alongside these, standards such as RdSAP (used for EPC assessments) and the AECB’s Carbonlite New Build and Retrofit Standards offer alternative frameworks for improving building performance, each with varying levels of rigour and flexibility.
This quick guide explores:
• How Passivhaus standards from the Passivhaus Institute (PHI), including EnerPHit, align with and complement PAS 2035 in retrofit projects.
• The strengths and limitations of other standards such as RdSAP and AECB Carbonlite, offering a comparative view of retrofit compliance frameworks.
Download the PDF below to access this Advice Pack. Access the PAS to Passivhaus Comparing Retrofit Standards Table.
Readers that would like this document in a more accessible format should contact rise@turntown.co.uk.