Repairing split wood siding boards: a handy how to

Poor nailing often results in split boards. If you're faced with split wood siding boards, avoid further damage and repair them yourself. Here's a handy how to and five extra tips.

• Chisel
• Exterior PVA woodworking adhesive
• Tape (if required)
• Wood block, screw and wedge (if required)
• Exterior-grade putty (if required)

• To repair a split you'll need to glue the two segments of the board back together.
• Lever the split open with your chisel and squeeze in some exterior PVA woodworking adhesive.

• Hold the split closed while your adhesive dries.
• Duct tape may be strong enough to hold it closed.
• If it's not, screw a block to the bottom of the board and drive a wedge between it and the bottom edge of the glued board.

1. To avoid splits, fix boards with a single nail at each stud and always drill pilot holes.
2. To stop splits when nailing wood siding, blunt the sharp end of the nail with a hammer. This won't work at the ends of boards so always drill pilot holes first.
3. The part of a board most likely to rot or decay is the end grain. As it dries, this part of the board acts like a sponge, soaking up moisture. When replacing boards, always be sure to give the end grains an extra generous coat of primer or oil stain before fixing them in place. Do this and your walls will last much longer.
4. If a nail doesn't hold securely when hammered, it could be because the wood behind the weatherboard is rotten or insects have damaged it. Whatever it is, correct the underlying problem before repairing the cladding.
5. Fix warped boards to the studs with long screws to flatten them out. Drill and countersink pilot holes to avoid splitting the boards. Use exterior-grade putty to conceal the screw heads.

Follow this handy how to and you'll be better able to repair your split boards yourself.