Round wire nails are the bread-and-butter fixing for sawn timber, but you can’t use these for plasterboard or exterior work, where a galvanized fixing is needed to prevent staining. Lost head nails should be used for visible second-fix work, such as installing an architrave, and nails with a spiral shank give the best grip for metal fixtures, such as joist hangers. There are also floorboard nails with a rectangular profile, called cut nails, which ensure the boards don’t pull away from the joists as the timber moves.