Wood worm on upstairs Joist

[markwm]

Been doing some work in an upstairs bedroom, removed some floor boards to run some cable and spotted a pile of what looked like sawdust near the end joist.

On close inspection, the top of the joist where I had removed the floor board crumbled away. I removed all the loose material with a chisel and hoover and the pics show what's left.

Obviously it's wood worm, it just appears to be mainly in this location. The joist end that sits in the (exterior) wall is fine. The joist is adjacent to next door so there's no chance of that wall being wet. The joists are dry as a bone.

I took a picture down the length of the joist and whilst there are more holes there's nothing anywhere near as bad as the section underneath the floorboard I lifted.

pic looking down the length of the joist...

holes on the underside of the floorboard, there's also holes in the top of this floorboard.

Luckily the joist is a 9" so it's still solid enough IMO. Is it worth taking up all the floor boards along the length of this joist and treating it? or should I just treat the area's where there's holes? I have some cuprinol 5 star in the garage.

My question though is, how do I know the woodworn has gone? this may have been here years, I don't know but am sure there's no leaks that are causing the joist to get wet.

 

[joinerjohn]

Trouble with woodworm is, once you notice the holes, the beetles have matured and gone. The larval stage of common furniture beetle (which seems to be the culprit) lasts around 3 -4 yrs, but there again , your timbers could have been infested years ago when your house was first built.
Attacks are usually (but not always) confined to the timber near where the end grain is exposed, but can spread over the years as adult beetles will lay eggs in flight holes.

 

[gregers]

take a looksie in your attic and check the timbers there.
if so lay a pieice of white paper under said holes and bang rafter/timbers to see if any frass comes out (very fine dust)if lots then it could be fairly fresh and then you will have to decide about having youe place sprayed for woodworm?

 

[Blagard]

lay a pieice of white paper under said holes and bang rafter/timbers to see if any frass comes out (very fine dust)if lots then it could be fairly fresh and then you will have to decide about having youe place sprayed for woodworm?

You will get fine dust out of any woodwormed timber in this sort of situation. A lot if the infestation was moderate to heavy.

Personally I would suggest that as the OP has some Cuprinol kicking around, coat what you can see and reach but don't worry about it.

These days with fitted carpets the woodworm beetle has a hard time getting at timber. Plus the transfer of the larva from house to house in old infested furniture is really a thing of the past.

By all means inspect all visible timbers and if you find woodworm extensively then consider a professional treatment.

Since it is also possible the house has been treated already, it can be worth checking if guarantees of the treatment were filed with the property deeds, as this happens sometimes if a mortgage inspection required the work.