What is a SAP Calculation?
The method of assessing if a dwelling meets the requirements of Part L1A/B of the building regulations 2013. SAP is the energy model used to calculate the overall energy efficiency and the fabric efficiency of a dwelling.
A SAP calculation is required
For all new residential Dwellings, conversions and for some extensions usually one which have large amounts of glazing. Building Control or your approved inspector will usually require the SAP calculation prior to start of works.
The things assessed by the SAP Calculation
- If the buildings thermal elements meets the minimum U value requirements.
- The predicted CO2 emissions of the building. (DER / TER)
- The Fabric Efficiency – How well the dwelling retains the heat generated (DFEE)
- The dwellings services meet minimum requirements
Info we require to complete your SAP calculations
- Any planning conditions with regard Energy
- Building Drawings including plans, sections and elevations
- Site plan
- Architectural construction details – build up of walls, floors, roofs etc
- Details of heating plant, hot water lighting and ventilation
- Thermal bridging details (contact us for more info)
- Air Leakage Tests result (again contact us for assistance)
- Details of any renewables that are planned for the development
To make life a little easier download our checklist of SAP Calculation requirements.
Tips on ensuring your dwelling gets a SAP Calculations Pass.
- Contact us as early as you can, there is nothing worse than building the dwelling, only to find that it does not pass the SAP Calculations compliance test – we can help to ensure you pass.
- Don’t be fooled into thinking meeting minimum U values will get you a Pass. Insulate as well as possible
- Build for a good Air leakage test – keep things airtight.
- Specify thermally efficient windows and doors – aim for a glazing U value of 1.2w/m2k
- Thermal bridging, thermal bridging and thermal bridging – you will not pass unless this has been addressed – Check out more detail here or call / email us.
- Consider renewables – though not always required, this can be a convenient solution to gaining compliance to you SAP Calculations or Part L compliance