Window frames would need a complete redesign - in proposed changes to the building code

Suggestions include having climate zones - which would mean new houses in Queenstown would have to triple glaze windows, but warmer areas would only need double glazing.

Window and Glass Association technical manager Robert Campion says most of our joinery isn't built for the added weight and load on hardware.

He says our windows systems aren't designed for triple glazing, and they're looking at double glazing alternatives.