by A thesis submitted to the University of Plymouth in ... - PEARL home

Energy Performance of Buildings Directive, which came into being in 2002, has
a stated purpose 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".
This has led, at the national level, to revisions of Approved Document Part L to
the Building Regulations. Compliance had previously been possible through an
elemental method whereby a whole building was considered sufficiently energy
efficient if each element, such as floor, wall, roof, etc. met minimum standards
of insulation. This has been abandoned in favour of a Standard Assessment
Procedure (SAP) to calculate a building's overall environmental impact in terms
of energy use and carbon emissions. Dedicated software programmes have
been developed to carry out the calculations, such as the Simplified Building
Energy Model from the BRE for non-dwellings, or numerous private sector
software packages recommended by the BRE for dwellings.
SAP 2006 recognises that volumetric heat capacity of materials, commonly
referred to as their thermal mass, can play a part in reducing overheating in
buildings, and hence saving on cooling energy. However, it does not yet provide
a calculation methodology or suggestions for dedicated passive solar designs
whereby solar or other passive gains are stored in thermal mass for later
release (Todd S, 2006).
A reliable and economical method of measuring volumetric heat capacity, and
thermal diffusivity, could further the attainability of passive solar, low or zero
carbon design and allow hard data to be used in modelling building designs.
Once such savings can be accurately and reliably quantified and measured,
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