GLOSSARY OF TERMS
The method for calculating the TER (the minimum energy performance
requirement for new dwellings). A SAP rating is produced, on a scale of 1-100.
This is then presented on a SAP certificate.
NB. It is not possible to directly compare the ratings calculated by SAP 2001 with ratings
produced from SAP 2005. The scale of SAP 2001 used a different rating of 1–120.
Also the CO2 output was scored differently.
The method for calculating the TER for non-domestic buildings/
commercial buildings.
Target carbon dioxide Emission Rate – this is the energy performance target
that must be achieved to comply with the requirements of the Approved
Document. It is expressed in terms of kg/m2/yr. The TER is calculated
using the SAP software.
Dwelling Emission Rate – this is the CO2 emission rate for the proposed
dwelling. It is expressed in terms of kg/m2/yr.
In practice two DER calculations may be needed - the first at the design stage,
based on plans and specifications used in the submission to the Building
Control. The final calculation of the DER should be based on the dwelling as
constructed, including any changes made and including the results of the air
permeability test.
The objective of the European Union Energy Performance Building Directive
(EPBD) is to “promote the improvement of energy performance of buildings
within the Community taking into account outdoor climatic and local
conditions, as well as indoor climate requirements and cost effectiveness.”
The fuel factor is used when calculated the TER. The fuel factor takes into
account the higher carbon emissions of fuels other than mains gas and is
applied where the main form of heating for the proposed dwelling is not mains
gas. The fuel factor has the effect of reducing the penalty of using fuels other
than mains gas for the proposed dwelling.
The ‘notional dwelling’ is the benchmark against which the 20% energy saving
is assessed. The reference values to be used in the notional dwelling are set
out in Appendix R1 of SAP 2005.
This is a measure of the amount of heat that passes through a square metre of material which is one metre thick with a temperature difference of one degree (Kelvin).
This is a measure of the insulating qualities of a material. The lower this figure is the better the insulation value.
This is a measure of the ability of a material to prevent the passage of heat. Thermal resistance (R) of a material with a thickness (d) in Metres and Thermal Conductivity (I).
R=d/I | 
