Is this wet rot or dry rot ?

topcat105

I noticed rising damp in the corner of the living room (terraced house party wall).

It seems to be coming from under the stairs so I took off the wooden board which hides the underside of the stairs.

The 2 wooden "struts" either side are rotten from the base up.

Is this dry rot , wet rot , woodworm or something else.

Can I just replace the affected wood or do I need to get an expert in ?

TIA for any advice.

grumpy_codger

Looks like woodworm to me. In this case you need to treat the adjoining timber and the replacement.

WIAWSNB

Surely connected with the presence of the damp?

Obviously the first thing to address will be the source of damp itself. It's a very defined tide mark - could it be from a leak rather than ground-rising?

When did you notice it? Can you say when it wasn't there?

In essence, tho', the repair is to cut away all the rotted timber and any damaged brick/mortar, coupled with removing some of the solid timber beyond this tobesuretobesure, soaking everything in killer (dry,wet,worm), and replacing the missing bits, ensuring anything structural is restored.

Section62

https://forums.moneysavingexpert.com/discussion/6684463/is-this-wet-rot-or-dry-rot

I noticed rising damp in the corner of the living room (terraced house party wall).

How old is the house? Do the external walls have a DPC? Are the floors suspended or solid?

I'd say rot rather than worm, but that's only from what I can see in the pictures. Regardless, some of the wood looks untreated, so you'll want to treat it all with a wood preserver (including insecticide) while you've got access to the whole area.

Bigphil1474

From what I can remember - We had what we were advised were weevils in our old house cellar, attracted by the damp conditions. Looks a bit like wood worm but we got a damp company in to do a survey and they were clear it wasn't. We improved ventilation and the damp improved, weevils died off.

Agree with above - need to sort out the cause of the damp, then do the repairs. If it's the party wall, speak to the neighbours as they may have the same. When we had those works done, we also had the garden wall to one side cut back away from the house as it was causing some dampness on the party wall. Not as bad as yours looks though.

jimi_man

That doesn't look like woodworm at all. We have woodworm holes in our workbench (long since treated but the holes remain) and they are small dotted holes all over the wood. I'd say that's almost certainly caused by damp.

Looking at the first picture of the tide mark up the wall, that looks exactly like what we had in our last house two years ago. In our case it was caused by a leaking radiator pipe under the (concrete) floor which was traced very quickly by a leak detection guy, but obviously there can be many causes - bathrooms, faulty guttering, roof issues as water does tend to travel! I'd be looking at something like that first of all.

topcat105

Thanks for the replies.

The house is over 100 years old. It's a solid concrete floor.

I had a damp course done in 2008.

I noticed it not long after that wall was painted in the summer.

I've been in touch with a leak detection company so will see what they say.

Severn Trent have been replacing all the main pipes in my road so maybe that has something to do with it.

Thanks again everyone.

Section62

https://forums.moneysavingexpert.com/discussion/comment/82150413#Comment_82150413

Severn Trent have been replacing all the main pipes in my road so maybe that has something to do with it.

If that has resulted in the water pressure increasing it is possible it has caused or exacerbated a leak in a pipe in the walls or under the floor, but otherwise unlikely.

A solid concrete floor with no dpc under it can cause wood which is in contact with it to start rotting - in your case it does look like the rot has started from the bottom and is working upwards.

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/82150413#Comment_82150413

Which wall is that, exactly? (Plan?) How far along each wall does the damp show? And what, if anything, shows on your neighbour's side?

topcat105

So the leak/damp detection guy has looked at my photos and emailed me his thoughts....

The 2 pieces of wood either side of the understairs have wet rot and an old infestation of wood boring weevil.

The floor must have been raised at some point as they go 4 inches deep into the concrete. As was suggested the damp has been slowly creeping up from the base.

So all timber to be replaced and floor gaps filled.( I might just leave as it is as its hidden.)

Luckily it's not weight bearing just a frame to attach the outer board.

The tide mark on the wall could be a residual mark from masonry chemical biocide from when I had dry rot treatment at same time as DPC.

Sorry I didn't mention this before, I didn't think it was connected.

I've pencilled along the mark to see if it expands over the next few weeks. If not i can paint with stain cover and then repaint.

The wall has been beige for years and only recently green so now more noticeable.

Neighbour has no sign of damp on their side.

Fingers crossed ...

Albermarle

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