Ashrae 90.1 isn't a guideline? Its a set of massively prescriptive and defined rules for assessing buildings against benchmark buildings.

We have a similar document to some extent in the UK. The national calculation methodology document that accompanies the iSBEM energy calculation tool available from the BRE outlines how to model in accordance with UK regulations or at least it does to some extent.

Ok whilst writing this I've altered my opinions and so both are probably worth adding to list as they do have some useful information on how to define zones, etc rather than just being code style documents.

Kind regards

Paul

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Dr Paul Carey