Going to spend the rest of my life de-nailing!

[JobandKnock]

The old dry rot myth.

Cut off its water supply and dry it out and it's dead as a dodo.

Ah yes, the old myth that if you cut off its' water supply, it's dead as a dodo.

It often doesn't die when you cut off its' water supply, it can become distressed, in which case it will generate a fruiting body. It as likely to become inert - until the next time there is enough water to reactivate it. It can survive in that state for decades.

Because it can live in lime plaster and lime mortar it can spread a long way from a fruiting body, which is why on infected walls we generally replace any unseen timber to masonry connections (e.g joists pocketed into brickwork) with resin anchored steels which in turn carry new timbers. The worst places for dry rot are where timbers such as beams are pocketed into damp outside walls and on the top floors of buildings where roofs and gutters have been inadequately maintained , leading to a supply of water. Once dry rot has damaged timber beyond a certain point, robbng its' strength, the only resolution is to cut out the affected timbers and replace them

 

[Adam W.]

Ah yes, the old myth that if you cut off its' water supply, it's dead as a dodo.

In fact it often doesn't die when you cut off its' water supply, it can become distressed, in which case it will generate a fruiting body, but often it id as likely to become inert - until the next time there is enough water to reactivate it. It can survive in that state for decades.

Because it can live in lime plaster and lime mortar it can spread a long way from a fruiting body, which is why on infected walls we generally replace any unseen timber to masonry connections (e.g joists pocketed into brickwork) with resin anchored steels which in turn carry new timbers. The worst places for dry rot are where timbers such as beams are pocketed into damp outside walls and on the top floors of buildings where roofs and gutters have been inadequately maintained. Of course once dry rot has damaged timber beyond s certsin point Rob ing its' strength, resolution is to cut it out and replace

It's a fungus, once the moisture content falls below 22% it dies and like most things, once it's dead, it's dead. (mummies and zombies excluded)

For example, if you buy a bag of dried shitake mushrooms and put them in water, they don't suddenly spring back to life.

Edit.

Oh, and Vampires, they're tricky to kill.

 

[Jacob]

We had dry rot here. Underfloor vents had been blocked, damp proofing had been badly installed, underfloor rubbish had not been cleared away. Fixed it by fixing those 3 things and added another vent "periscope" as it was partially underground (a split level basement). I played safe by applying Boron solution on new timbers - just brushed on no great problem.
I've left various access points where you can pop in a mirror and shine a torch to see how the underfloor is getting on - seems fine so far, 20 years on, perhaps took 2 to 3 years for things to dry out thoroughly

 

[Adam W.]

Mind it doesn't suddenly spring back to life.....WooOOOOoooOOOO!

 

[Jacob]

Mind it doesn't suddenly spring back to life.....WooOOOOoooOOOO!

Well it did briefly spread over new timber which was a bit of a scare, so I had to lift boards and apply Boron solution to the underside of the boards and more to the floor joists. It didn't come back.
Come to think I might go and have a look - this is the perfect weather for it warm, damp, light wind.
Dry rot is alarming because it can spread so quickly and visibly - the under floor space covered in spooky fine white webbing with shiny drops of moisture glittering in the torch light.
All the floor joists stood on bricks at about 2ft intervals, these on a hardcore rubble sub floor which was slightly damp, so I also put a patch of black plastic DPM on each brick. The sub floor also dried as air circulated through the unblocked vents. These things can take a long time to dry out.
Trip down memory lane - I've just remembered the huge fruiting body about 3ft across on a vertical wall behind match board panelling! It really does make its presence seen! Burnt the wood, applied heat to the wall, no prob.
Part of the drama of dry rot is that it flourishes in dark unventilated places where nobody goes - hence grows steadily unseen for a long time. Can be a shock when it's finally revealed.

 

[OldWood]

Is there someone here with qualifications that can clear up these dry rot opinions please.

I've always been brought up with the guidance that dry rot is a fungus and as such it will produce fruiting bodies - the fruit being spores, like any fungus, which are really very difficult to get rid of totally, and if given adequate moisture and warmth will develop into the fungus and the associated mycellia.

So I am with JobandKnock and not Adam W on this, but can't back up my opinion.
Rob

 

[Jacob]

.... if given adequate moisture and warmth will develop into the fungus and the associated mycellia.

Spores are with us all the time - there is something rotting nearby, everywhere.
If the moisture and warmth are taken away the thing can't survive. Nor can anything else.
I was a bit hasty putting boards back in my basement and should have given it longer to dry out.
Time is the issue - chemical treatments speed things up but you still have to remedy the cause; damp and lack of ventilation.

 

[Adam W.]

Is there someone here with qualifications that can clear up these dry rot opinions please.

I've always been brought up with the guidance that dry rot is a fungus and as such it will produce fruiting bodies - the fruit being spores, like any fungus, which are really very difficult to get rid of totally, and if given adequate moisture and warmth will develop into the fungus and the associated mycellia.

So I am with JobandKnock and not Adam W on this, but can't back up my opinion.
Rob

Yes, me. I was taught by Dr. Brian Ridout

Dry rot, Serpula lacrymans spreads by mycelium which is a collection of hyphae and reproduces by spores produced by the fruiting body, which is the bracket looking part, as Jacob described.

Hyphae/mycelium come first and do the damage, when the thing matures or thinks it's going to die it produces the fruiting body and the spores. Once it's dead, it won't spring back into life. But given the correct environment, the spores will germinate and produce new hyphae and the cycle starts over again.

That's about it.

 

[Jacob]

This is what it looks like when it really gets going. My fruiting body was like the pics - like a 2 to 3ft pancake stuck to the wall about half inch thick. dry rot fruiting body pictures - Google Search

 

[Sgian Dubh]

Hyphae/mycelium come first and do the damage, when the thing matures or thinks it's going to die it produces the fruiting body and the spores. Once it's dead, it won't spring back into life. But given the correct environment, the spores will germinate and produce new hyphae and the cycle starts over again.

It seems to me that's what JobandKnock might have observed, i.e., new active growth initiated by rewetting and some spores from the now dead source of the earlier/original fungal infestation. And having observed this 'renewed growth' then perhaps mistaken it as reactivation of the original infestation. Just a speculative thought on my part implying no criticism of anyone here that's already made a contribution on this Serpula lacrymans diversion in the thread. Slainte.

 

[kinverkid]

Same kit as mine! More or less. I use a rare earth magnet instead of metal detector.
I'd add scrub plane as useful addition - doesn't matter if they hit a nail they only are for rough cutting and very easy to sharpen

I do have a wooden block plane modified as a scrub plane for that reason. I use it to take paint, varnishes and in-grained dirt before putting it though a thicknesser. My earth magnet is the thing with a bit of string on, works a little like a diviner. Every time I look at that photo I see I've missed something off. Like the bolt croppers for snipping long nails.

 

[Adam W.]

It seems to me that's what JobandKnock might have observed, i.e., new active growth initiated by rewetting and some spores from the now dead source of the earlier/original fungal infestation. And having observed this 'renewed growth' then perhaps mistaken it as reactivation of the original infestation. Just a speculative thought on my part implying no criticism of anyone here that's already made a contribution on this Serpula lacrymans diversion in the thread. Slainte.

Going by what Ridout says, it requires a very specific set of conditions for the spores to germinate and produce new hyphae.