Where all insulation material within the building elements external walls, ground floor, roof and building services has a Green Guide rating of A or A+ the Mat 03 Calculator would not need to be completed as the insulation index would always be 2 or greater.
Evidence would still be required as follows:
- Marked up plans/elevations and/or a copy of the specification confirming the location of insulation materials
- Manufacturers literature of the given product
- The Green Guide rating and element number/bespoke green guide rating for the assessed insulation specifications.
In this instance it would not be necessary to provide the volumes and thermal conductivities of each insulation type; however, you must be satisfied that all relevant insulation has been accounted for within the assessed building.