DIYbanter - View Single Post - Woodworm - sorry, long post

Invisible Man[_2_]

wrote:
On 19 Jul, 23:18, Invisible Man wrote:
Ctimescale.

Thanks again. Is there anywhere more appropriate I could post this?

Dear ? (can't see who you are!)
Comments are as follows

Bought 40 year old house a couple of years back.

Comment
A house that young may well have active woodworm as it will not have
had time to die out naturally from lack of subtstrate (sapwood) and
natural predators

Kitchen floor now uneven under vinyl covering. A few months before
bought it there was a major escape of water when occupiers were in
Spain. Ply & hardboard flooring now found to be warped.

Comment
Not really pertinent to viability or not of a CFB attack

Having moved bits under fitted kitchen, rolled back vinyl and levered
up
part of floor found evidence of woodworm. Hole size and shape suggest
common furniture beetle.

Comment
Check the frass. (Faecal pellets). If they are gritty and the holes
are normal 1 to 1.5 mm size - chances are you are right
If it is hard wood and the frass is like talcum powder you are wrong
and there is not a long-term problem

Stuck some tissue across some of the holed areas to see if
infestation
is still active.

Comment
Uncommonly bright idea - well done. You are a jump ahead of 99% of the
population. Wait until September for the end of the flight season.
Ideally wait for 3 years to be sure of no further activity.

Since found some holes under under stairs cupboard and cloakroom -
all
on the same side of house. Before discovering this I had lifted one
or
2 boards in lounge and diner and saw no evidence. These latter 2
rooms
are immaculately decorated, furnished and newly carpeted and I would
rather not disturb them.

Comment
If you end up having to treat them - they could be treated with a
fogging machine to avoid taking up the floor or by a variety of other
non-destructive methods of which I could advise at the time

If infestation is active presumably enough boards will have to be
taken
up to allow spraying of all the joists etc.?

Comment
It depends on just how active it is. I would (as a professional) be
obliged to do a COSHH assessment. You can get away with much less in
the "must do" department. Just follow the advice on the can! If there
is minimal activity - a few holes- then partial treatment folllowed by
monitoring is reasonable (look at the advice on the Codes of Practice
for treatment from the HSE)

Some sites suggest getting moisture content below 12 percent would
cause
the outbreak to die out.

Comment
I disagree. I have seen active woodworm in furniture at a much lower
mc than this and I suspect such sites are the result of reading books
written by so called "academic" experts who operate from a lab (if
they have done any work at all!) and have not done much field work.
The discussion is pointless as you will never get the mc that low all
year in a structural GF building timber.

Doesn't seem damp under the floor but I would
have to hire or buy a meter to find out. Air bricks are all clear.
House
is in Essex where it is relatively dry.

Comment
Not pertinent- mc reduction will only reduce the rate of attack not
total control

Anyone got any advice?

Comment
Carry on monitoring
Let me know if it is soft or hard wood
and a rough idea of the % of sap v heart
The number of holes per 100 mm square
whether or not it is confined, scattered or generally spread about

Work will be a little delayed whilst we find the money to:
Get the woodworm treated if necessary.

Chris George
Many thanks for this Chris.
It is difficult to get the floor up and the vinyl suffers more damage
each time. I will wait until September when I will check if there is any
evidence of new flight holes.
The tissue idea I found suggested in a couple of places on the web
amongst heaps of dubious other ideas.
The holes are in joists which I assume are softwood. There are dozens
rather than a handful. To my inexpert eye does not look enough to be a
structural problem at the moment.

Thanks again.