Evidence centre
We separate measured results from models, supplier statements and proposals. Where evidence is not ready, the calculator receives no credit.
Build your home planThe current public tool is a screening model using stated energy use, tariff and performance assumptions. It does not include installation cost, finance, maintenance, degradation or replacement unless clearly added to a future project case.
Heat-pump performance is a whole-system design assumption that must be checked against room heat losses, emitters, hot water and controls. Heat Saviour compatibility depends on version and hydraulic design. VorteXtract is a wet-heating gas-removal product, not a ventilation device; the base model assigns no saving uplift.
PassivGlas analysis must use installed whole-window Uw values. Ventilation proposals must disclose airflow, fan power, noise, controls and commissioning; no heat-recovery benefit is modelled without tested product data.
Gateway Pro can add time-stamped monitoring after installation. Measured use remains distinct from weather-adjusted estimates, and consent and data minimisation apply throughout.
The developing Home Energy Model calculates a standardised home across 17,520 half-hour periods. It can improve assessment detail, but it is still a model. Breathe keeps that assessment track separate from consented, measured operation in the real building.
Applicable domestic retrofit may require a PAS 2035 process and Retrofit Coordinator. TrustMark, funding schemes and Building Regulations can add installer, evidence, energy and ventilation requirements. The exact route depends on the property, work, nation, funding and date, so it is checked before design. An EPC or grant threshold is a minimum, not a complete building strategy.
Evidence in context
Our retrofit evolution case study separates published test-house outcomes, Breathe’s strategic interpretation and modelled planning figures.
Read the case study
People before products
