dry rot and the fixing there of. EDIT could be wet rot!!

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mickthetree

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Evening all

Just been to view a house that we would like to buy. In an area we like, nice size garden for the little one (and any others that come along) and potential space to expand at a later date.......and possibly a nice size workshop, ahem.

The house is approx 1900ish

On inspection the are some areas of concern including some areas of plaster coming off on the wall below the chimney stack, which doesnt concern me too much as once the leak is fixed it can be replaced.

The one area I dont know a lot about is dry rot. There is clear evidence of this in the downstairs, to the point that there is a hole in the floor showing a beam that is rotten through. Some of the floor boards are rotten, but most seem sound.

I dont have a problem with the idea of replacing the beams or floor, but does dry rot have to be cured in some way? Or is it a manifestation of a bigger issue? such as the house may require a damp course adding? Does it typically mean ripping out all of the wood and getting rid? There are no air bricks in the wall.

I'm going to have a google round now and see what else I can find on dry rot, but thought I'd ask the combined brain here for their thoughts.

Many thanks in advance.

Paul
 
Fixed up a mates house years ago and the timbers had dry rot and wood worm. We replaced all the affected floor joists with new ones - "wrapping" ends and sprayed the dung out of everything with a Boron solution. Nothing heard of since.

Dry rot is a fungus - so wonder what airbricks will do for it. On the subject of airbricks - ours is a 1918 house, and I've heard it from a few folk (professionals) that I should not put any in & if there are any - remove them.

HIH

Dibs.

p.s. These are the folk we used for the Boron stuff - http://www.boron.org.uk/
 
Dibs-h":1nzsbb8w said:
....
Dry rot is a fungus - so wonder what airbricks will do for it. On the subject of airbricks - ours is a 1918 house, and I've heard it from a few folk (professionals) that I should not put any in & if there are any - remove them.
....
Couldn't be wronger.
It's damp air and lack of ventilation which causes dry rot. Air bricks (and other drying measures) may be the cure.
Wet rot is caused by direct wetting; rain ingress, leaky pipes etc. and so is easy to fix.
Main thing is not to panic, even though dry rot in full steam looks very scary like a horror film and if not dealt with is very destructive.
If it's your own house you can take some simple measures and monitor them, but if it's for a client most go for serious overkill, they don't want to be called back!
 
Jacob":1w4u96pm said:
Dibs-h":1w4u96pm said:
....
Dry rot is a fungus - so wonder what airbricks will do for it. On the subject of airbricks - ours is a 1918 house, and I've heard it from a few folk (professionals) that I should not put any in & if there are any - remove them.
....
Couldn't be wronger.
It's damp air and lack of ventilation which causes dry rot. Air bricks (and other drying measures) may be the cure. Wet rot is caused by direct wetting; rain ingress, leaky pipes etc.
Main thing is not to panic, even though dry rot in full steam looks very scary like a horror film and if not dealt with is very destructive.
If it's your own house you can take some simple measures and monitor them, but if it's for a client most go for serious overkill, they don't want to be called back!

Jacob

Our 1918 house was built without airbricks and with the exception of the front lounge all the timbers in the house are original. I know 1918 sounds antique but there are a lot of houses older than that and still in good nick and I don't think all of them have airbricks.

Dibs
 
Cheers guys.

There was a fine mesh of what looked like roots on top of the floor boards (which was under lino which was under carpet!).

I noticed that the ground level under the floor joists seemed quite high. This could probably do with reducing as well as adding air bricks.

Having said that, I think the ground level was possibly as high as the floorboards so air bricks would be underground.
 
Dibs-h":11ktlexf said:
....
Our 1918 house was built without airbricks and with the exception of the front lounge all the timbers in the house are original. I know 1918 sounds antique but there are a lot of houses older than that and still in good nick and I don't think all of them have airbricks.

Dibs
That's OK then if you haven't got a dry rot prob, but if you have got dry rot then ventilation is most of the answer, or if you have air bricks and block them up you might get it later.
mickthetree":11ktlexf said:
..
There was a fine mesh of what looked like roots on top of the floor boards (which was under lino which was under carpet!).....
That's dry rot - but if it looks dry it's probably dead but there will be spores about which a damp spell could trigger off..
Taking the lino off might be all you need to do. It's bad news on suspended ground floors as you can get condensation on the underside, with little chance of drying out.
Opening and ventilating the under floor space will help too.
 
Mick, In wood dry rot breaks the timber, such as skirtings, up into square (ish) blocks that become dry and crumbly, in a void, such as beneath floors it looks exactly like very dense cobwebs.
If you have white threads in brownish stains it's wet rot.

Roy.
 
cheers guys I feel like I'm getting more of a handle on this.

Seen a good youtube vid which shows exactly what you mention Roy.

As long as we can get a mortgage on the place with it having the problems then I can do most of the work myself.

Some suggest that good ventilation and prevention of water getting in (leaks etc) are much more important than getting an injected dpm / dpc

We'll see what the expert has to say.
 
Dry rot and wet rot are both wood-decaying fungal infections. Their names are typically misleading as both require the wood to have an elevated moisture content that is around ~20% (in-service wood is between ~9-14%).

Wet rot gets it's name by virtue of the wood generally feeling wet (but not saturated) because of an elevated source of moisture in the vicinity - typically caused by an overflowing or leaking gutter/drain etc. Remove the source of moisture and the decay is halted once the wood dries back down (the fungus cannot decay the wood any further without a water source but the damage may have been done!)

Dry rot, like wet rot, also requires a similarly high moisture content to initiate decay. Unlike wet rot though it has the ability to transport the water it requires from great distances (tens of metres in extreme infestations) through the fungal strands (mycelium) to the active site of decay. The mycelia can coalesce into quite thick strands in a large infestation. Because of the lack of an obvious warning sign (leaking gutter etc) there is often no sign of a problem with dry rot until the wood starts crumbling beneath your feet!. As the name suggests the wood is generally dry to the touch but where the mycelium are actively decaying the wood there will be a localised high moisture content. Because of it's ability to find water and re-initiate an infestation dry rot is a more insidious problem than wet rot and you have to generally remove the entire infestation and the infested wood before treating the surrounding area. Seek professional help if you are concerned that it may be dry rot

BTW, wet and dry rots are collectively known as brown rots which typically manifest in the wood as a brown discolouration and a series of cube-like cracks. The first stage of decay is for the fungus to break down the wood into smaller chunks first and they can cause serious degradation to the structure of the wood without it being obvious - a very simple analogy would be to imagine chipboard having all the internal glue bonds removed. What is left may have the appearance of a sound product but it has been drastically degraded from within. This is why it is good practice to remove any brown rotted wood from any structural situation even though the decay may seem minimal. Wood-decaying fungi like stagnant air to get started so a good airflow is also beneficial in keeping them in check!



Brian
 
Jacob":u8tfhtv0 said:
Opening and ventilating the under floor space will help too.

We have cast iron grates at just above ground level ventilating the underfloor crawl space under the ground floor - these look to be original.

I suppose when I was referring to air bricks - I meant those higher up say at 1st floor level.

Cheers

Dibs
 
Neither problem will automatically prevent you getting finance Mick, what has happened with me is that the loan company retains part of the agreed finance till the problem is dealt with.
If one company says no, try another!
It is a usfull means of arguing the price down! (hammer)

Roy.
 
Thanks again all

Essentially, if they wont lend us the full amount we wont be able to buy it, which is the worry. Still, if its meant to be......

I would love to go back and have another look now I feel I have a handle on it more. We will get an expert to take a look over it. It needs remedying sooner rather than later no matter what happens.

Brian, I really appreciate your explaination. This makes what I have read online much clearer.

I'm sure there must be an underlying issue which caused it in the first place. I couldnt identify it when I was there though.

I would hope that taking out all of the wood regardless of condition would not be necessary.

Amazing stuff, fungus!
 
Essentially, if they wont lend us the full amount we wont be able to buy it, which is the worry. Still, if its meant to be..

That depends on the amount, I borrowed the difference from my bank. My solicitor handled it all.
On another occasion they paid the full amount and i was given a deadline by which time the work had to be completed and pass inspection, which is why I said try more than one lone company if you hit problems, it pays to shop around.
Remember this Mick, if you're having difficulties so will any other would be purchaser so it may pay to talk to a loan company about this sort of problem and ask what their policy might be.

Roy.
 
My partner and I bought an Edwardian terrace house in the early 1980s. It was our first property and we had a full structural survey done which highlighted some minor problems which we were quite happy to fix ourselves. After living there for under a year, we had to take up a floorboard in the lounge for some reason and discovered a nasty fungus smell under the floor, some red spores a fruting body and typical threads of dry rot all over the wall and some of the joist ends :-( The underfloor cavity seemed dry and it appeared there was no direct damp ingress there, but there was a fair amount of rubble and rubbish lurking under there which we removed. We ripped up the floor, removed and replaced any timber with threads/spores on and treated the whole underfloor area, brickwork and floorboards with some really nasty expensive chemical spray stuff. Replacement & exiosting sound joists had there ends wrapped in DPC material before refitting. We also retrofitted more and better airbricks in the external walls to increase underfloor ventilation.

This cured the problem for us - and we later discovered the source of the infection was the next door house which *did* have a serious damp & dry rot problem (caused by leaking bay window flat roof & rising damp which was fixed by the new owner when the house changed hands) and our infestation had come through the party wall intent on munching on our floor in under a year (it had not been evident when the structural survey was done). The dry rot threads can carry their own moisture with them from a damp place to a dry place to extend an infestation. When researching the matter I read reports of it climbing up inside brickwork to infect timbers on the first floor if left untreated - which I found quite scary at the time :-(
 
The worst case of dry rot I have seen was from 'next door' as well. The cellar looked like something from a horror movie with 'curtains' of dry rot strands everywhere.
When pointed out to the neighbour he simply shrugged his shoulders and ignored it!

Roy.
 
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