Coef Wall

An engineered collection of our empirical case studies, precise methodological breakdowns, and critical industry insights.

A ranked bar chart of building junctions ordered by their contribution to SAP transmission heat loss, with the longest, most conductive junctions at the top
Methodology

Which Junctions Actually Move Your SAP Score - Our Junction-Impact Review

Not every junction is worth calculating. Before you commission anything, we rank your details by how much each one adds to the dwelling's heat loss, so you spend on the handful of junctions that move the SAP result - and leave the rest on conservative defaults.

A 2D thermal model of a junction showing the internal surface temperature and the coldest point in the corner
Methodology

How We Assess Surface Condensation & Mould Risk

A guide to our standalone surface-temperature assessment - proving that a junction stays warm enough to avoid condensation and mould, when a building control body, warranty provider or insurer asks for evidence.

A 3D thermal model of a party wall meeting the ground floor, showing heat escaping through the foundation into the surrounding ground
Methodology

How We Calculate the P1 Junction (Party Wall to Ground Floor) in 3D

A guide to the SAP junction that can't be captured in a single section — why the party-wall-to-ground-floor junction (P1) needs two full 3D models, and how BR 497 turns them into the Ψ-value your assessment needs.

A 3D thermal model of a rainscreen bracket crossing the insulation layer, showing the heat path short-circuiting through the metal
Methodology

How We Calculate 3D U-values for Rainscreen & SFS Facades

A guide to our method for build-ups where metal brackets, rails and steel studs pierce the insulation — why a hand-calculated U-value overstates their performance, and how we model the repeating bridge in 3D to get the figure that counts.

A 3D thermal model of a building corner where two walls and a floor meet, showing the temperature gradient across the junction
Methodology

How We Calculate 3D Thermal Bridges

A guide to our method for the junctions a flat section can't capture — balcony connections, structural penetrations and three-way corners — and the standards behind every figure we report.

A 2D thermal model of a wall-to-floor junction showing the temperature gradient across the detail
Methodology

How We Calculate 2D Thermal Bridges

A guide to our method for assessing linear thermal bridges — the heat lost at junctions, the risk of condensation, and the standards behind every figure we report.