Joining Timber Floor Joists

1 ft 0 3048 m.

Joining timber floor joists.

Sheet materials mdf hardboard chipboard osb plywood door blanks. The nail specification used is dependent on the thickness of the joists being used. The following table gives details of allowable spans and spacing between joists for the most common timber sizes used in floor construction. All the figures are based on normal domestic floor loadings where the floor construction is typically 18 25mm floor boards sheets with up to 12 5mm thick plasterboard and skim underneath.

Splitting the wood does no good. When the sagging joists are level apply a generous bead of construction adhesive to the existing joist. Sawn carcassing timber cls studwork timber carcassing timber batten fencing timber joists. Live load is weight of furniture wind snow and more.

Use your common sense when deciding how many fasteners are needed. Dead load weight of structure and fixed loads 10 lbs ft 2. True floor joist span calculations can only be made by a structural engineer or contractor. 1 psf lb f ft 2 47 88 n m 2.

Pictured at left is a diagram of some recommend prescriptive repair techniques for floor joists. Mouldings planed timber planed timber mouldings skirting cladding wood flooring window boards. But it s usually best to run the sister joist over the entire span. Maximum floor joist span for no.

This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. In this case the framer used 9 8d nails on each side of splice which is adequate in this case. Compare click to add item 3 1 2 x 14 i joist 90 series to the compare list add to list click to add item 3 1 2 x 14 i joist 90 series to your list sku 1066950. Bolting two timber joist together for additional strength and cutting treaded rod.

In this case the framer just needed a longer rafter. Driving 16d common nails in old hard wood is difficult. If you are doubling up floor joists creating trimmers or trimming joists around stairs and chimneys they all need connecting properly so that they can act as a single unit.