Wet timbers

[nowtaboutnowt]

Hi
I was in my loft finishing some plaster boarding when I noticed a nail on the ridge board (the big piece of wood that runs the length of the roof at its highest point I think) was rusty and on closer inspection I found the ridge board to be 85% saturated (got a gadget). The wood that is wet sits on the chimney stack/breast and is only wet for about 12inches then is dry again.
I will be getting onto the roof to locate the leak on hopefully seal it.

The question I have is, if I stop the water penetration would it be ok to leave the timber to dry out or would that wet bit need replacing for fear of rot?
Also I don't know how long this has been letting in water

Cheers

 

[JohnD]

there is a considerable risk that it will have rotted and insects will be eating the rotten wood (woodlice don't eat sound wood).

Poke it thoroughly with a flat-ended screwdriver to see (the reason for a flat one is that it doesn't leave a round hole that will look like insect damage next time you inspect it).

Some photos may help with ideas on how best to repair it.

 

[nowtaboutnowt]

Cheers John

Will do some poking.... And photos might not show much as it is tucked up above the stack, but I'll try tonight and see if they show anything.

Are you also saying that those pesky woodlice eat from the inside out?

The other thing that bothers me is that even with all this Amazonian rain we've been having lately all the other timbers and felt are dry around the offending timber and like I said earlier only 12 inches or so in length is damp, could the timber soak up moisture from the brick if this was getting wet from the rains?

 

[JohnD]

woodlice don't tunnel, they just slurp at the rotten wood (they have practically no teeth so can't damage anything sound). It's always a bad sign to find them in your house (they need water to lay their eggs in).

Badly rotted wood sometimes has all sorts or insects crawling about in it, including millipedes and beetles (I presume some of them eat the smaller insects) and these can be deep inside if there is a cavity. Damp can get inside through knots and shakes in the timber, and I suppose small insects can crawl in the same way. I recently found wet rot in some construction timber I'd treated and used for fence rails, rainwater had penetrated through knots and bypassed the preservative and water-repellent stain on the surface

Bricks will absorb quite a bit of rain and let it evaporate in dry weather, I don't know how wet they have to be to make timber wet. You usually find this under floors, where the damp has been fairly continuous and it never dries out.

 

[nowtaboutnowt]

My initial thought on replacing if it turns out to be soft and deteriorating(please fell free to correct me) would be to accro the ridge board, cut away the damp bit and replace with similar timber by strapping to remaining board. Or am I too ambitious....!
Will the roof fall in?
How many accros?
All expert advice warmly welcomed.

 

[JohnD]

picture! picture!

 

[nowtaboutnowt]

Will do when I get home tonight.

Cheers