Dry Rot

[Anonymous]

There is dry rot in the ground floor, and we propose to remove all the timbers and rebuild the floor. The walls are stone. Old Pine panelling covers much of the walls and meets the floor and we would very much like to save it. Barring one patch, which will be removed, it shows no sign of rot.
We would like to adopt a "wait and see" approach, to see if drying out the building helps. That said, is there any regime or product that might assist, or any tips from those who have experienced this. Thank you. Ross.

 

[Anonymous]

Why do you thnk its dry rot? May it just be a wet rot? Do you have substantial mycelium growing and penetrating masonry and large reddy coloured half rounded fruiting bodies shedding red dust?
Dry rot is far more difficult to control than wet rot and could need more extreme measures so an accurate diagnosis is necessary.

 

[Anonymous]

Jon

Thanks for the reply. What is showing is a cream/light beige colour growth. Is there any website or book which helps in identifying the difference between wet rot and dry rot?

 

[Anonymous]

If you look at the post a few days ago on chemical attack I left an Isbn number of a bre timber decay book. I think its out of print but your library should have it, I have put the link to the BRE Bookshop site.
However if the fruiting body is the colour you describe it is not dry rot, if its the mycelium it could be.



http://www.brebookshop.com/

 

[Anonymous]

Jon

Thanks for the post. I read what you said about the colour and that is helpful, but I didn't follow the reference to mycelium. Can you clarify. Thanks

 

[Anonymous]

Mycelium are frond like fingers of rot growth which carry moisture and nutrients around. You should find some pictures on the net somewhere. Fruiting bodies are where the fungus produces spores from and can vary greatly in size shape and colour. The colour of the effected wood can also give clues to the rot type especially taking into consideration the cracking pattern.
I hope you find some references to establish what you have.
Hopefully it is just wet rot and easier to control with a few simple measures, i.e. ventilation, correct use of lime mortar etc.

 

[Anonymous]

Jon

Thanks, noted. I have some pictures on the Internet that are helpful.

Ross

 

[Anonymous]

Any help?



http://images.google.co.uk/imgres?imgurl=http://www.healthy-homes.co.uk/Cuboidal%2520cracking%2520sign%2520of%2520dry%2520rot.jpg&imgrefurl=http://www.healthy-homes.co.uk/wetdryrot.html&h=151&w=250&sz=11&tbnid=MB6VbwD8aiTMqM:&tbnh=64&tbnw=106&hl=en&s

 

[Anonymous]

http://www.diydoctor.org.uk/projects/dry_rot.htm

 

[Anonymous]

David

Thanks for the links; much appreciated! I see that this link shows chemical treatments for timbers that might become affected. Does anyone have experience of them?

Thanks

 

[Anonymous]

Article on Graham Coleman's website describes the use of borates in teh control of Dry Rot. Technically, they're not necessary if you can dry out the timbers and monitor to ensure that they remain dry. But you have to weigh that up against the damage that dry rot can do if it starts to spread again.


http://www.buildingpreservation.com/Dry%20rot.htm

 

[Anonymous]

It wont start to spread again if it remains dry. Any idea what caused it Ross?

Remove only the decayed sections of timbers- you shouldn't need to take up an entire floor. I assume there's a focus to the outbreak.

Matt

 

[Anonymous]

Thanks for the post.

I have been reading up about the Danish experience where they hot-air blast the spores out of existence.

Ross

 

[Anonymous]

Matt

Thanks for the post. Blocked drainage outside is letting water in. That is being cured by renewing the drainage outside the building.

Inside, I'll take the advice and cut back what is rotted.

I mentioned in an earlier post that the Danes believe in hot-air blasting the spores out of existence.

Here is a link:

http://www.cordis.lu/itt/itt-en/01-2/innov02.htm

Ross

 

[Anonymous]

"I mentioned in an earlier post that the Danes believe in hot-air blasting the spores out of existence. "

Spores are produced by fruiting bodies (the sexual stage of the fungus). The chances of a dry rot spore germinating on a susceptible piece of timber are effcted a great deal more by the condition of the timber than the number of spores or the proximity to a fruiting body. The Danish method then is not just killing the spores, it's apparently killing the mycelium and any fruiting bodies too.

The thing is.....

.....turning the water off kills the fungus (all stages), so why bother with the heat treatment? If you haven't fixed the source of water ingress the timber will still be susceptible to attack and if you have, then the fungus will die anyway.

I'm sure it works quite well given the fact it's pretty easy to killing something that's already dying. It speed up teh drying process, I suppose.

It sounds like you've got the dry rot beaten, Ross. Don't mess around with any uneccessary work.

Matt Green

 

[Anonymous]

Thanks for the post. Will do