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

"To dramatically improve the sustainability of the built environment by radically
transforming the way it is planned, designed, constructed, maintained and
operated" (UK-GBC, 2007).
The UK-GBC, along with organisations such as the Energy Saving Trust and
the Carbon Trust, offer hope that environmental impacts of buildings will be
reduced with regard to energy efficiency, although the current regulatory
framework does not recognise the extent that passive heating and cooling can
contribute towards lowering emissions from buildings. This is despite solar
irradiation falling on a typical 80M2 UK building footprint being in the region of
88 MWh per year (Energie-Atlas GmbH, 2007), over four times the average,
measured energy usage of existing buildings in south west England, at 21.5
MWh per year (Chambers et al, 2005). An obstacle to the take up of low energy,
passive solar design is the lack of reliable thermal data on building materials.
The upgrading of existing buildings and the thermal modelling of all new
buildings, under current regulations, requires heat loss calculations for the
building envelope. These are based on the thermal conductivity of the materials
used, as in standard U value calculations. The following two sections consider
the thermal data sources and measurement methods currently relied upon in
building design. The chapter concludes with a rationale for adopting the thermal
probe technique.
Data sources for the thermal properties of building materials
There are three distinct areas from which building designers can currently
obtain thermal data for building materials. These are:
o
Published values
Commissioned measurements
18