How to apply woodworm treatment?

[bebeboeuf]

We had a leak that saturated some floorboards. We have cut out the worst of them but have noticed the odd woodwork beetle over the last few weeks.

Carpet will be going back down in 3 weeks so I thought I would apply some woodworm treatment which is in liquid form to the surrounding timbers and joists.

Has anyone done this and can give tips?

I have. I like to use a wood preserver on the joists of the bathroom and kitchen, because water spillages and leaks are possible, and dampness encourages both worm and decay, and also in any area where there are signs of previous damage.

I use a spirit-based preservative such as Cuprinol Clear, because I find it soaks in better than the water treatments. There are cheaper own-brands, but read the list of ingredients on the safety label to check that they are equivalent.

Because these treatments are poisonous, you must wear disposable overalls, or something that will withstand a maximum wash, and cover exposed skin, hair and especially eyes. use plastic gloves, not rubber, which is broken down by some solvents. I use blue nitrile disposables. Remove any clothes that are wetted with the fluid, and wash the skin thoroughly. Do not wear soiled clothes the next day, unless they have been laundered and line-dried.

i use a large soft brush, with bristles long enough to winkle into crevices and joints. The instructions usually say apply two or more coats, applying each after the previous has soaked in, but not dried. If you are using a coloured fluid, shake or stir the can thoroughly as pigments tend to sink to the bottom. Colours help you to see any missed or thin patches.

Have the maximum possible ventilation while working, and while it dries. It will smell for a couple of days, and then when you put the radiators on next winter, the heat will drive out a bit more. I recently used a Wickes product which has a pine-like smell, not unpleasant. Leave the floor open so it can dry, don't cover it up.

There will be some spills and splashes. On a ground floor it doesn't matter, but if there is a ceiling below it may mark the plaster. I fold newspaper to lie between the joists. Have some kitchen roll to mop up spills.

Before starting treatment, sweep up and vacuum all dirt and dust. There is no point in applying the chemical to layers of dirt, and they will obstruct the fluid getting to the timber. It is also easier to see old damage on clean wood, and any new damage will be more noticeable. This will also remove any dead beetles or husks.

Professionals use a sprayer, and lift something like one floorboard in five so the spray can reach the joists. Using a brush really only works if you have taken the floor up, or if you're in an unfloored loft.

Thanks so much Pigletjohn.
This is the stuff I’ve bought

Do I need to do the top of the floorboards too even though they are varnished?

Il be able to lift most of the boards as they were all stripped out and screwed back down so ready enough to get up before the skirting goes back on

it doesn't soak into painted or varnished surfaces.

This seems to be he worst affected floorboard where exit holes appear the most.

Strangely this is the furthest away from the point the floorboard were wettest

p.s.

clean any rubbish that shoddy builders hid under the floor. This often includes rags, scrap wood, shavings and sawdust, which will encourage pests and insects.

very clean-looking holes, they must be fairly new.

The leak was nearly 6 months ago now and insurance have said everything is dry enough.
We had dryers and dehumidifiers in.

It’s a Victorian subfloor area and to me it’s not perfectly dry yet as the ground underneath doesn’t feel dusty enough to be

Could they be spreading? Am I best getting a specialist in?

check that your airbricks are not obstructed by cobwebs, dust, extensions, paving or flowerbeds. The subfloor space should be cold and draughty.

The lifecycle of woodworm can take years from eggs to emergence. If you treat the timbers, and ventilate the subfloor void, I wouldn't worry yet.

Modern, centrally-heated houses don't have enough humidity for the beetle to survive, I'm told that's why worm is less common now than it was fifty or a hundred years ago. If you are fond of old antique furniture, or have a wood-burner and bring in logs, you may be bringing in more infestation.

Parts of Surrey have a particular problem with the Long-Horned Beetle, and any suspicion of that must be professionally treated.

Woodworm like a bit of damp and a bit of warmth. So they tend to be in bathroom floors, and in lofts close to the hatch where warm air gets in, and near leaky radiators where the wood is a bit damp.

You can drip woodwom killer down those holes, then fill or stain them, so that any new holes are easily recognised. A live infestation also leaves "frass" (beetle droppings) where they are active.

If you want to test the timber for damage, poke it hard with a flat-ended screwdriver. Don't use anything pointed, because any round holes will be mistaken for wormholes by the next person who looks.

If you find any timber that is weakened or riddled, it has to be cut out and replaced with new.

We aren’t in Surrey and last time I saw a live beetle I checked against online photos and it is definitely a common furniture beetle

The under floor void in winter feels very cold and drafty.
Right now not so much but it’s a warm day

We have air bricks - 1 at front, clear, 2 alone the side, I cleared those ones recently and the one at the rear has been covered with an extension (although still there, it vents into the extension rather than outdoors)

There was a slow leak under the floor before we moved in a few years ago so based on the life cycle these flight holes could be from beetles that had been laid years before the current leak maybe.