Woodworm in furniture: the signs, how to tell it from termites, and how to treat it

It is most likely the dust left by woodworm, the common name for the larvae of several small beetles that live and feed inside timber. The female lays her eggs in open pores and cracks on unsealed wood. The larvae tunnel through it, turn into adult beetles and bore out, each leaving a small round hole and a little heap of powder beneath it. Most of the insect's life passes out of sight: the University of California's pest management programme (UC IPM) puts the life cycle of the common powderpost group at about three months to more than a year, depending on temperature, moisture and the quality of the wood.

The signs to look for:

• Small round holes of even size, mostly on unpainted parts such as the back of a cabinet, table legs and the underside of drawers.
• Fine powder in small piles directly below the holes. UC IPM describes the powder of the common powderpost group as feeling like flour or talc when rubbed between two fingers.
• Small brown dead beetles on window sills, around lamps or in drawers.
• In a badly affected spot, wood that feels crumbly and gives under firm pressure, with edges that break away.
• In a heavy infestation, sometimes a faint ticking in the wood at night. Wood also ticks as it moves with changes in temperature, so new holes and fresh powder are the more reliable sign.

Dry powder and round holes mean woodworm; mud and damp soil mean termites. The risk to the house and the treatment both differ, so settle this first. If you see both kinds of sign, or cannot tell, leave the traces as they are, do not sweep up the powder, and take close-up photos for a professional.

Woodworm turns up most in unfinished timber, new timber, plywood, rattan and bamboo, and old furniture that has stood for a long time in a storeroom. Timber that was not treated thoroughly when it was processed, or that is kept somewhere damp, is often affected too. Wardrobes and bookshelves are frequent cases, because the back and the inside are usually left unfinished and the piece is seldom moved.

UC IPM sorts the woodworm found in homes into a few groups, told apart by the size of the hole and the feel of the powder. It suggests trying the tip of a ballpoint pen in a hole to judge the size.

Old holes can be many years old with nothing left inside, so test before you treat. The check takes a few weeks:

• Vacuum up all the powder around the holes.
• Cover the existing holes with paper masking tape, or mark each one in pencil.
• Slide a sheet of dark paper under the piece.
• Look again after two to four weeks. Fresh powder on the paper, new holes or tape that has been pierced mean the woodworm is active.
• Old powder tends to be discoloured and clumped. Fresh powder is pale and loose, like wood that has just been sanded.

For a picture frame, a wooden box, a craft piece or a small stool, cold works without chemicals. UC IPM records that keeping a small wooden item in a freezer at 0°F (about −18°C) for 72 hours can kill the woodworm inside it.

• Seal the item in a thick plastic bag before it goes into the freezer, to limit condensation.
• Check the temperature with a thermometer. The freezer compartment of a household fridge is often not cold enough; a separate deep freezer is preferable.
• Afterwards, let the item return to room temperature inside the sealed bag before opening it, so that moisture does not settle on the wood.
• Do not heat wood at home with an oven, a powerful hair dryer or a heat lamp: the risks are fire, warping, cracking and a ruined finish.
• Keep the item apart from other wooden things until you have confirmed that the woodworm has stopped.

On a small item it is possible, with care. Woodworm and termite products are sold for brushing on, spraying or injecting into the holes. For door frames, floors and built-in wardrobes, let an eligible provider assess first, because treatment done wrongly can miss part of the infestation and spoil the finish. If you do use a product yourself:

• Choose one with a label in Vietnamese that states what it is for and its registration number, and read the instructions before you start.
• Penetrating products work only on bare wood. Existing paint or varnish stops them soaking in.
• Wear gloves, a mask and eye protection, and work in a well-ventilated place away from flames and heat.
• Do not use it on wood that touches food, such as chopping boards, trays and wooden bowls, or on children's wooden toys, unless the label allows it.
• Never mix products, and store them out of reach of children and pets.

Seal the wood and keep it dry. The female beetle needs open pores or cracks in bare wood to lay her eggs, and an adult that emerges from one piece can lay in unpainted wood nearby. UC IPM recommends paint or varnish to close the pores and cracks. A coating prevents new eggs; it does not kill larvae already deep inside.

• Once you have confirmed the woodworm has stopped, fill the holes with wax or wood filler, sand, and recoat the whole surface, including the back and the underside.
• Examine second-hand furniture, clearance timber, pallets and wooden crates before they come indoors, looking at the back, the underside and the legs. Keep anything doubtful apart for a few weeks.
• Some woodworm prefers damp wood. Repair leaks, and ventilate storerooms, the space under the stairs and built-in wardrobes that back onto a damp wall.
• Do not leave unpainted wooden items stacked against each other in a closed store for a long time.

Call when the timber is part of the house, when several pieces are affected, when the wood has lost strength or the piece is valuable, or when you cannot tell woodworm from termites. UC IPM advises replacing infested structural timber where that is possible.

The survey is free and answers three questions: woodworm or termites, which pieces have live woodworm, and how far the damage goes, including in the pieces standing nearby. Holes and powder are marked and photographed as a baseline for later checks. You then receive a written list of the items to be treated, the method for each, how long to stay out of the area and an all-inclusive price to approve. Most furniture is treated where it stands; a heavily infested piece may be treated separately, and floorboards are lifted only with your written agreement.

UpClean's own pest-control technicians apply the treatment with products that hold a valid registration number in Vietnam. An Up specialist, one of UpClean's identity-verified and trained staff, empties the cupboards, covers the floor, walls and neighbouring furniture, stays through the visit, vacuums up the powder, wipes the wood as the technicians direct and puts everything back. UpClean has declared its eligibility to provide pest-control services as required by regulation; the declaration and product information are available on request.

The Up Report that follows, by WhatsApp or Zalo, contains the photos of the marked holes, the points treated and the dates of the follow-up checks; the warranty terms for each method are set out in the written quote. To book, send close-up photos of the holes and powder to 0968 726 135 on WhatsApp or Zalo, between 7:00 AM and 8:00 PM on any day. Quotes, confirmations and the report can be in English. You are given the specialist's name and photo ahead of the visit, in case your building requires outside staff to be registered with management.

Woodworm treatment

How each kind of timber item is prepared, cost factors and areas covered.

Termites in Saigon houses

If what you found is mud tubes, hollow timber or shed wings.

Cockroaches, ants and geckos in Saigon apartments

Cockroaches or ants found at the same survey can go into the same written quote.

Book a survey

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