We have built an extension and had the base built for us ~ the usual layers of hardcore, sand, DPC, rigid insulation, more DPC and poured concrete. Because we want a 'traditional' timber floor, we allowed for joists and floorboards.
At last inspection BCO said we needed air-bricks to ventilate under the floor. I pointed out that the floor was insulated and waterproofed etc (which he had forgotten) so he then said we had to insulate between the joists so there was no gap under the floor. This means a hefty extra expense and more insulation than the floor really needs. Why not a space under the floorboards?
If it is to do with internal moisture 'collecting' and condensing in the space, would a VCL under the floorboards suffice?
I don't usually question a BCO, but his response was a bit vague as if he wasn't quite sure. I do appreciate it's not the standard way to do a floor ~ being a mix of two types of construction!
Any guidance gratefully received!
