Replacing Rotten Roof Timbers

First remove the rotten wood and then replace it with new rafters.

Replacing rotten roof timbers.

If wet rot occurs in structural timbers such as roof trusses floor joists expert advice should be sought as the implication for structural integrity must be established. Wood beams are used to support a bearing load from a roof or second floor. When you come across rotted wood in your old house projects instead of replacing the damaged wood you also can repair it with specialty epoxy penetrants also called consolidants and fillers to make repairs. A new piece of timber is cut a to replace the damaged piece and the joists plates are positioned ether side of the joists with the end of the joist plate right up against the edge of the timber so it is the joist plate that site on the bearer a.

When repair is no longer an option the roof rafters must be replaced. Inspect and assess the damaged section of timber and determine where it needs to be cut to prop the timber along it s length using suitably sturdy props such as acro props once supported cut off the damaged end leaving only solid un damaged timber now. These plates are a quick and neat solution for joist ends that aren t going to be seen. This project requires two parts.

If you were able to keep the removed section in one piece measure it. Use a polyester filler to rebuild rotted or damaged wood. The length also reduces the fulcrum effect so there shouldn t be any great stresses applied to the existing timber. In other areas the rotten timbers should be removed and replaced.

If not climb the roof and measure the opening so you can cut the replacement piece to be a perfect fit. Not only is this faster but the fixed wood is stronger than the original. Replace the roof decking select plywood or oriented strand board that is the same thickness as the wood you are replacing. The joist plate is bolted to the timber making the joint b as strong as the original joist.

You can mold and shape it to match the original wood profile. A combination of replacing rotten or failed timber with new timber and strengthening with resin bonded steel or carbon fibre rods can be adopted to good effect in many situations. Some companies will even supply pre shaped repair pieces with the rods already bonded in place ready to fix to the prepared end of a failed timber. They can span as much as 20 feet and many times they can be doubled as decorative pieces.

If the damaged area is fairly small it can be cut away and a new piece of timber joined to that remaining. The basics of the process are as follows. Wood rotting from the inside out compromises the structural integrity of the rafter.