BB101 or TM52

[evnov]

Hello

Im new to this forum but seek some clarity. I have done a few searches and read up a number of topics on this forum but havent really come to a conclusion as of yet (hence this post)

For a while now i have been modelling schools on IES and running the overheating assessment against TM52. I have recently had a request from the client to run the building to comply with BB101 instead.

I was under the impression BB101 was under revision and previous version was superceeded by TM52 ?

apologies if this is a novice question but i am a little stumped.