Cut in roof membrane and a void below.

[Palomino_G210]

Hi:

I just discovered a cut, 1/2" to 3/4 " long, in my rubber roof and there is a void a little bigger than a large egg, rotted or soft wood I imagine, below the cut. Probably been there for a while. It is near the edge and at the intersection of a longitudinal beam and a cross beam. What is the best way to repair it?? Do I open the hole up large enough to replace the wood? Do I just seal the hole and live with the void? Undo the edge and lift the roof membrane, if that is possible, to get at the problem.

Please let me know what your thoughts and experience is in this situation.

[pgandw]

Rot is actually a fungus that feeds off of wood fibers. The best treatment (from work on boats) is removal and replacement of any soft or rotted wood. There are chemical treatments (Git Rot used to be one) that claim to penetrate the wood, kill the fungus, and strengthen the remaining fibers - I have never used the stuff.

Any source of moisture into encapsulated wood is a setup for rot. Wood must breathe (it will do so through paint) or must be totally sealed.

If the beams are affected in the slightest, the affected area (plus a little) should be removed, and new wood sistered on to replace the lost strength of the removed wood.

I would prime all the reachable wood with a wood preservative to prevent any remaining spores from starting over. Then of course, make sure the roof is fully sealed with no leaks.

Not really any different from repairing a leaking house roof where the rafters and/or sheathing have softened from the leak.

Fred W