Thursday, 27 May 2010
Why do you need a SAP Calculation?
With Governmental and Public focus on C02 emissions, Designers and Developers need to consider the impact that their designs are having on the environment like never before. Part L1a of the Building Regulations requires that SAP calculations are carried out on all new build developments to prove that they are not contributing excessively to carbon emissions. Each dwelling must demonstrate that it meets the Target Emission Rate as stipulated within the SAP calculation.
There are 2 stages for the SAP Calculations. The Design Stage is completed and submitted at the same time as your building control application to your Building Control Body or Approved Inspector. If there are changes to the specification after the Design SAP has been completed then the Building Control Officer or Approved Inspector may request that an amended Design SAP is submitted.
The As-Built Stage is calculated when the premises is complete. From the calculation a 'pass' Certificate will be produced for submission to the Building Control Officer or Approved Inspector.
Approved Document Part L1A
Part L1A is to do with Conservation of Fuel and Power in new dwellings and is just one part of the Building Regulations in England and Wales. Since the government announced that it intends to reduce the UK's carbon emissions by 60% by the year 2050 there has been a concerted effort to look at ways of reducing emissions from within the built environment. 50% of the UK's carbon emissions can be attributed to the built environment so it stands to reason that the biggest cut backs can be made in this area. Part L1a contains the legislation that aims to make this happen.
There are five criteria which must be met to achieve compliance. One of these criteria is that the Dwelling Emission Rate should be equal to or less than the Target Emission Rate. This is achieved using the government approved calculation methodology, which in this case is the SAP calculation. Other factors that are covered by Part L1a include air permeability rates, restricting U values and limiting solar gains in summer.
EPC (Energy Performance Certificate)
The Energy Performance Certificate is now a mandatory requirement for all new homes completed after 6th April 2008. The certificate sets out the dwellings sap & energy efficiency ratings and also has a list of recommended upgrades in order of cost effectiveness. The certificate is required for the sale of the property.