The timber necessary to provide nailing for the outer sheeting is assembled and then diagonal bracing is introduced in such a way as to give connected triangulation to both head and jamb framing. Timber-frame domestic buildings vary from those of traditional brick construction mainly in the walls and partitions. In all timber constructions, protection against damp either from wind and rain, capillary action or condensation is a necessity; great care must be taken in detailing and following up to ensure that this takes place. The set out of the foundation work for timber frame construction is less complex than for traditional brick buildings. All the timber work must then be protected using metal or other suitable flashings extending above the floor and turned out to the edge of the foundation wall. A mastic sealant may be applied in strip form or with a gun to isolate the timber finally from the brickwork.