Alternative weather files

Different or newer weather files can be used instead of those referenced in the manual, as long as they achieve the aim of the credit. Weather files based on climate projections with higher temperatures than those specified in the relevant criteria, set a more robust standard for overheating and so they are acceptable. The alternative weather files need to include same variables as the specified weather files e.g. dry bulb & wet bulb temperature, wind speed & direction, solar altitude & azimuth, cloud cover etc. for each hour of the year. It is the role of the assessor or design team to verify this and ensure that meeting the BREEAM criteria does not become easier by using the alternative weather file.