QUESTION:

What engine/algorithm does ECOTECT use to do thermal analysis, heating and cooling loads etc. ?

ANSWER:

ECOTECT uses the CIBSE Admittance method for it's thermal calculations. This is a internationally regarded method used by engineers (CIBSE = The Chartered Institute of Building Services Engineers) and designers. However, as with all simulation methods, there can be variation. For this ECOTECT will quite easily export to other thermal packages such as EnergyPlus and ESP-r. This allows you to consider a design using several methods including ECOTECT’s own internal calcs via the admittance method.

There is more detailed information on the CIBSE Admittance Method and its implementation in ECOTECT in the ECOTECT help file.

Or for even further reference and details on formulae etc. please refer to CIBSE Guide A which details their Admittance Method in full cibse.org.