For your own peace of mind and to satisfy Building Control these should be undertaken before you start work on site.
If you don’t have your SAP calculated professionally, you could easily add £1,000's to your construction costs through unnecessary renewables and costly heating systems.
The 
Energy Performance Certificate (EPC) gives home owners, tenants and buyers information on the energy efficiency of their property.
The Code for Sustainable Homes was launched as part of a package of measures towards zero carbon development, including an overarching consultation: Building A Greener Future on the shift to zero carbon.
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