Wood borer treatment in Wilderness

Tiny round holes in a pine ceiling, a little cone of powder on the floor below, and a beetle on the windowsill in spring. Here's what that means in a Wilderness house, and what to do.

Wood borer in a Wilderness home is treated once we've confirmed it's active. Exposed, unsealed timber such as roof trusses, battens, pine ceilings, floor joists and the undersides of floorboards is sprayed with a registered product that soaks into the surface, killing larvae close to it and beetles as they chew their way out. Sealed or varnished timber and furniture are injected through the holes instead, and badly infested furniture can be fumigated away from the house. Old holes with no fresh dust don't need treatment at all.

We inspect and treat houses, holiday cottages, guest houses and lodges in Wilderness and on the hills around it.

Why it turns up here

Wood-boring beetles lay their eggs in cracks and old exit holes in timber. The larvae then spend a year or several tunnelling inside the wood before they pupate and chew out as adults. Two things help them along in Wilderness: a damp, mild climate, which suits several of the species, and houses with a lot of exposed softwood. Pine tongue-and-groove ceilings, timber floors, exposed rafters in older holiday cottages and furniture that has moved from house to house over the years are all on the menu.

Which beetle?

• Common furniture beetle. Small round holes, about the size of a pinhead or a little larger, in furniture, floorboards, ceilings and stairs. It favours older, slightly damp timber
• European house borer. Bigger, oval exit holes, found in pine rafters and battens. This is the serious one, because the larvae can spend years inside rafters and battens weakening them
• Powderpost beetles. Very fine, flour-like dust from hardwood items like mouldings, picture frames, flooring and furniture

A clear photo of the holes with a coin next to them, sent by WhatsApp, helps us narrow it down before we come. Our wood borer beetles profile has more detail on each.

Is it still active?

Old holes are common in older houses and mean nothing on their own. Active borer shows as:

• Fresh, pale powder under the holes, which comes back after you vacuum it up
• Holes with clean, light edges rather than dark, dirty ones
• Small brown beetles collecting at the windows in spring and early summer

If you're not sure, vacuum the area, put a sheet of dark paper underneath and look again in two weeks. New powder on the paper means something is still working.

How we treat

1. Inspection We go through the roof space, ceilings, floors, stairs, built-in joinery and any furniture you're worried about, to find the beetle, the extent and whether it's active.
2. Spraying Bare, unsealed timber in the roof, under floors and on exposed beams is sprayed.
3. Injection Holes and galleries in sealed or varnished timber, and in furniture, are injected.
4. Fumigation Heavily infested furniture is fumigated away from the living space, where gas is the only practical way to reach every larva.

For spraying and injecting, you don't need to move out; just keep people out of the room or roof space being treated until it's dry. Products are odourless and don't stain, though on a good finish we test a hidden spot first.

Guest houses and furnished rentals

Antique wardrobes, old chests and second-hand beds give a guest house its character, and sometimes its borer. A piece with active borer can seed nearby timber, so treat it before it spreads to the floors or ceilings. If you buy furniture at auction or from a sale, check it for fresh dust before it comes into the house.

Selling or buying

Wood borer is the main reason for the beetle certificate on a Western Cape property sale. If you're selling and you've seen fresh dust, have the timber treated before the inspection, so it doesn't delay transfer. If you're buying an older Wilderness cottage, the certificate tells you about active beetles; a separate check of the roof timbers' condition can tell you about old damage too.

Ceilings you're about to paint

If you're about to repaint or seal a pine ceiling, check for active borer first. Once a varnish or paint goes on, a spray can no longer soak in, and the only option left is injecting hole by hole. It's far quicker to treat bare timber, let it dry, and then seal it. The same goes for floors due to be sanded: treat after sanding and before the new finish goes on.

Damp makes it worse

A leaking roof, poor ventilation under a timber floor or a bathroom with no extractor keeps the wood damp, and damp timber is more attractive to several borer species. Fixing the leak and getting air moving under the floor protects the timber long after the treatment.

What it costs

The quote follows the amount of timber, which beetle it is, how easy the timber is to get to, whether we're spraying, injecting or fumigating, and how many pieces of furniture are involved. One chest of drawers is quick; a whole pine ceiling and roof space takes longer. We inspect first.

The full process is on wood borer treatment, and our other Wilderness services are on pest control in Wilderness. Phone 044 012 5011, or send a photo and your details.