About Heat Loss Calculator
Building a free, transparent, web-native thermal calculation platform for homeowners, installers, HVAC engineers, and energy assessors.
Our Core Philosophy
Heating design should never rely on opaque black-box tools or crude, outdated rules of thumb (such as arbitrary Watt-per-square-metre guesses). In an era where heat pumps and low-carbon heating systems require precise flow temperatures and emitter sizing, transparent calculations are vital.
Our platform exposes the actual U-values, design temperature differentials, and air exchange rates behind every single calculation, empowering users to verify and adjust every parameter.
Calculation Methodologies & Standards
Our tools implement standard physical steady-state conduction and volumetric ventilation calculations informed by:
- BS EN 12831: Energy performance of buildings — Method for calculation of the design heat load.
- CIBSE Guide A: Environmental design & Heating load data (Chartered Institution of Building Services Engineers).
- ACCA Manual J: Residential load calculation principles from the Air Conditioning Contractors of America.
- ASHRAE Fundamentals: Climatic design conditions and thermal properties of materials.
Technical Team & Review Policy
The platform is developed and maintained by building services engineers, certified energy assessors, and software engineers. All calculation engines and thermal reference tables are continuously reviewed against evolving building regulations and meteorological datasets.