Environmental Engineering Reference
In-Depth Information
or after October 2008 [2]. They are a result of EU Directive 2002/91/EC relating
to the energy performance of buildings [3], as transposed into British law by the
Housing Act 2004 and The Energy Performance of Buildings (Certificates and
Inspections) (England and Wales) Regulations 2007 [4].
6.3.2.2.2 Procedure
The energy survey needed to produce an EPC is performed by an inspec-
tor who visits the property and examines key items such as loft insulation,
domestic boiler, hot water tank, radiators, windows for double glazing and
so on. He or she then inputs the observations into a software programme that
actually performs the calculation of energy efficiency. The programme gives
a single number for the rating of energy efficiency and a recommended value
of the potential for improvement. There are similar figures for environmen-
tal impact. A table of estimated energy bills per annum (and the potential
for improvement) is also presented but without any reference to householder
bills. The householder will have to pay for the survey, which costs around
£60 for a four-bedroom house.
6.3.2.2.3 Domestic EPCs
The calculation of the energy ratings on the EPC is based on the RDSAPv3
procedure, which is a simplified version of the SAP2005. SAP is short for
standard assessment procedure and RDSAP for reduced data SAP; both are
derived from the UK Building Research Establishment's Domestic Energy
Model (BREDEM), which was originally developed in the 1980s and also
underlies the National Home Energy Rating (NHER) rating. EPCs have to be
produced as part of a home information pack by home inspectors or domestic
energy assessors who are registered under an approved certification scheme.
6.3.2.2.3.1 Property Details
The certificate contains the following property
details [5]:
1. Property address
2. Property type (for example, detached house)
3. Date of inspection
4. Certificate date and serial number
5. Total floor area
The
total floor area
is the area contained within the external walls of the
property. The figure includes internal walls, stairwells, and the like, but it
excludes garages, porches, areas less than 1.5 m high, balconies and any
similar area that is not an internal part of the dwelling [6].
6.3.2.2.3.2 The A to G Scale
EPCs present the energy efficiency of dwellings
on a scale of A to G. The most efficient homes—those which should have
