If you use the Acceptable Solution to comply with Clause H1, then opaque joinery, other than doors, should be treated as either a window or a wall.
All parts of the house's thermal envelope must limit heat loss consistently with the criteria specified in the Building Code or in the Acceptable Solution. Any reduction in the R-values specified for the walls, floors, roofs and windows will result in additional heat loss, and the house will not comply.
Insulation (R-values) can be traded between different parts of the building using the calculation method, the modelling method or the Building Performance Index (BPI). These methods allow louvres to be used in houses when a louvre does not meet the R-values specified for walls or windows in the schedule method.