Loft boarding and loft ladders

Modern insulation is deeper than the joists it sits between, usually 270mm against joists of 100mm. Boarding straight onto the joists crushes the insulation to a third of its depth, which costs you heat and can cause condensation in the roof space. Raised boarding solves it: a system of legs or a timber counter-batten lifts the deck clear, the insulation keeps its full depth, and there is a ventilation gap above it.

A typical job is a deck of tongue-and-groove boards over raised supports, a walkway from the hatch, and a light. Most lofts also need the hatch enlarged, because a 562mm opening is too small for most things people want to store. Weight matters: a domestic ceiling joist is sized to hold up plasterboard, not boxes, so a carpenter should tell you what the deck will carry and where the load-bearing runs are.