BC Energy Step Code: Building Envelope Performance Update
BC Energy Step Code: Building Envelope Performance Update
The BC Energy Step Code has updated the Thermal Energy Demand Intensity (TEDI) requirements AND added a new compliance option for thermal envelope performance. TEDI is a measure of the annual heating energy required to keep a building warm, which indirectly describes how well the building envelope retains heat.
The former approach listed a single TEDI value for each Climate Zone, meaning buildings in the coldest part of a Climate Zone would need to be designed to meet the same requirements as the warmest parts.
The new approach determines the required TEDI value based on the local Heating Degree Days of the project site. This gives a greater allowance for the modelled annual heating energy of buildings in the cold parts of a Climate Zone.
Although this relaxes the building envelope requirements, it is a favourable change because it means more towns and projects will be aiming to adopt the BC Energy Step Code, which has greater thermal requirements than the BC Building Code.
If builders do not wish to follow the new TEDI approach, they can follow the newly introduced alternate path for building envelope performance. This new approach mirrors the recently proposed change to the National Building Code of Canada, where compliance with a Step is demonstrated by modelling your proposed building and showing that it consumes a percentage better than a minimum code-built building.
- Step 2 = 5% better than Code
- Step 3 = 10% better than Code
- Step 4 = 20% better than Code
- Step 5 = 50% better than Code
Again, this will increase the adoptability of the BC Energy Step Code and drive the industry towards more energy efficient buildings.