identifying rot

[DanDIY]

I have got a rotten floor, but I am unsure if the rot is dry rot or a wet rot. I have used the http://www.buildingpreservation.com website which I found through searching through previous threads.

The damage is mainly limited to one ground floor room with a cellar underneath. The cause of the moisture was a blocked gutter and the overflowing water coming in through the cellar skylight, so I think we have this sorted.

About 6 or 7 joists have rotted clean through, so the floor will need replacing. This seems simple enough. The thing that has me concerned is that there are some isolated bits of rotten skirting board in another room. I cant see an obvious source of moisture here - its an internal wall and there is no plumbing, so I was concerned that this could be the result of a strand of dry rot. I haven't seen any evidence of these strand structures in my rot, so I am fairly certain that I am safe, but would like a second opinion.

I have taken some pictures:

Top view of the floor boards

One of the floorboards pulled up and fliped over

under the floor

This is the rotten skirting board in the other room

As far as I can see I have a cuboidal brown rot, which could be dry rot.

Any suggestions....

 

[gregers]

looks like dry rot to me.
google is your friend.

investigate the other rot you have found as dry rot can jump,or it could wel be another out break.

 

[AronSearle]

Looks like dry rot, though can't be sure from your pictures.

Dry rot does need moisture to progress, but it can transport moisture from wet areas to dry areas through brickwork, it doesn't just transport to sound dry timber unless it is adjacent. So unless the skirting is on the other side of the wall, I would consider it a coincidence, maybe old existing decay?

 

[maltaron]

It certainly looks like dry rot. Check for black cotton like strands on the brickwork. When you replace the floor either get the walls treated as dry rot can pass thro' walls, and behind plaster. We allways used to burn the brickwork with a blowlamp to kill the strands then spray everything in site with a nasty substance (of which I cannot remember what) which required us to wear protective clothing, masks and gloves. ( and that was before the elf & safety guys existed)