Once the concrete block upstands have set, a damp proof course (DPC) is laid between the upstand and timber frame work (150x50mm) to eliminate the chance of damp rising into the building. The framework is fixed together, with double joists around the perimeter with joist hangers supporting the spanning timbers. Once the floor has been insulated, and walls errected. 22mm moisture resistant tongue and groove chipboard sub flooring is laid. It is all finished with an engineered oak floor when the internal decoration is complete.