Design Stage SAP Calculations

Building Regulations dictate that a Design Stage SAP Calculation and Predicted EPC must be submitted to Building Control for new dwellings, before work can commence. Therefore a Design Stage SAP Calculation is a crucial first step in the building planning process. 

What is a Design Stage SAP Calculation? 

Using design plans, our consultants can conduct a SAP calculation on your proposed building in order to produce a predicted EPC. There is some degree of flexibility during the design stage,  as plans can be changed by architects to create a more energy efficient property, if the initial specification doesn't show compliance.

Moreover, as a result of the Design Stage SAP Calculation, Target Efficiency/Emission Rates are established based on a notional dwelling of the same size/dimensions:

The Target Emission Rate (TER) is the minimum annual CO2 emissions allowed by that dwelling and must not be exceeded by the actual CO2 emission rates, which is the Dwelling Emission Rate (DER), established based on the design of the property.

Target Fabric Energy Efficiency (TFEE) rates introduced in 2014 also accompany the TER, and is essentially the minimum energy performance required, expressed as kwh/m2 per year. As with TER, The TFEE must not be exceeded by the Dwelling Fabric Energy Efficiency Rate (DFEE) in order to comply.

What we can do

Once our energy consultants receive the relevant plans and drawings, they will use this information to provide a summary of elements such as heat loss from floors and roofs, as well as U-Values (the rate at which heat is lost from the building). All of this data is then entered into the SAP Calculation to produce the SAP Rating and predicted EPC.

Our consultants are able to model different variations of the proposed design if it does not meet compliance. They will then advise you on the relevant changes to be made. This could range from the type of boiler to be used, number of windows and roof insulation. 

Once a finalised version of the design is agreed upon, and the proposed building meets compliance, our consultants will produce a report that can be submitted to the Building Control Officer or Verifier (Scotland). 

Next Stage

Once the construction of the property is complete, an As-Built SAP Calculation must be completed to ensure that the property still complies with Building Regulations/Standards.