Replacing downstairs flooring - Noggins

[smeagol]

Hi all,

I'm about to replace the flooring in the dining room. Original floorboards have been lifted so many times the T&G is cut away from most of the boards. Also several boards have been replaced with ordinary planed timber. So floor is uneven and there is also a fair bit of bounce. Joists are 3.5" x 1.75" on 16" centres and it looks as though they are supported on sleeper walls, I've only taken 1 board up at the moment to check what needs doing. Subfloor is concrete and there appear to be some supports from concrete to joist in some places. house was treated for woodworm about 15 years ago, looks like just holes bored into flooring and treatment sprayed in.

The plan is to replace the flooring with 18mm P4 chipboard and add noggins and extra vertical supports to joists.

the questions:

Does that plan seem sound?

For the noggins and vertical supports can I use sawn treated softwood, I'm planning to get all the supplies from Wickes and can't see any structural timber.

Should I treat the joists for woodworm as I've got the floor up?

Thanks

 

[noseall]

wouldn't touch chipboard with a barge pole.

 

[masona]

Should I treat the joists for woodworm as I've got the floor up?

I wouldn't as long it's well ventilated via air-brick vents.

Where the floor joists resting on the wall plate, poke a small screwdriver to check for rot, very common in old properties, I don't know how old your property is though.

 

[smeagol]

smeagol wrote:
Should I treat the joists for woodworm as I've got the floor up?

I wouldn't as long it's well ventilated via air-brick vents.

OK you've got me curious now. Why does ventilation prevent woodworm? There are plenty of airbricks around the house, it's a semi built just after WW2, where the term Gerrybuilt came from I believe. From what I can see so far it's nice and dry under there so I'm presuming there is adequate ventilation.

 

[masona]

Read it here about chemical treatment, it's known to make people ill from Oilman link but it's not working yet, try again later. David P made a good post.