Need for an accurate understanding of the heating demand in order to correctly specify the energy system. Incorrect understanding can lead to wasteful or inadequate system specification.

Suggested actions

Before Implementation

Undertake in situ measurements and tests to establish whole building performance. e.g. air pressure test, room condition monitoring, U-value measurement etc. Undertake whole building energy numerical modelling (i.e. IES, Energy Plus etc.) using measured in situ data within model in order to make a thorough assessment of all contributory factors to energy performance and building heat demand. Improve fabric thermal performance and airtightness before installation of any low temperature heating system.

During implementation

Match the design heat demand to the proposed heating system rating. Avoid oversizing of heating system to maximise efficiency and coefficient of performance of system.

After implementation

Monitor 'as improved' results and building performance in operation and feedback results to add to knowledge of actual performance of buildings in use.