Hi, I'm thinking of insulation my loft, there is already some insulation between the joists. The joists are about 4 inches deep, if I'm gonna lay 270mm or about 10inches of insulations on top of the existing, then do I build the joists up to 10 inches or can I (as someone suggested) simply lat the new insulation in the other direction that the joists run in on top of the joists.
Thanks
Graham
Thanks
Graham