So this house...
Concrete roof tiles, on 2x2 battens, on foil, on 10mm (3/8) t&g pine sarking, on 10x2 rafters.
So basically no insulation.
The winters aren't cold and a 7kw inverter ac kept up, but in summer the tiles would send an ovenlike heat in to the upstairs living area. I shot the t&g...