Checking for Termites and Wood Rot Before You Buy

Termites and wood rot work quietly. From outside, frames and floors can look whole while the inside has already been eaten hollow.

Many houses in Kalimantan are built of timber. Even masonry houses use wood for door and window frames, the roof structure, ceilings and cupboards. This guide is for anyone buying a resale house, especially a timber house or a raised house on stilts, who wants to check it before making an offer.

Know your termites and wood rot

The common pest in homes is the subterranean termite. These termites live in colonies in the soil and reach wood through earthen tunnels they build. They eat wood from the inside and leave a thin skin on the surface, so the damage often can’t be seen. In a masonry house they can get in through cracks in the floor or gaps around pipes, then climb to the frames and ceiling.

Two other culprits are worth knowing:

• Drywood termites, which live inside wood without needing soil contact. The sign is small sand-like pellets piling up under the wood.
• Powderpost beetles, which leave small holes and fine, flour-like dust.

Wood rot is caused by fungi growing in wood that stays damp. The wood turns soft, crumbly and discoloured. Subterranean termites like damp wood too, so rot and termites often turn up in the same places.

Signs you can see and hear

Bring a torch, a small screwdriver and your phone for photos. Ask the seller’s permission before you probe any wood with the screwdriver.

• Mud tubes, small earthen tunnels running up walls, foundations, posts or along cracks.
• A hollow sound when you tap wood with the screwdriver handle.
• Soft wood that the screwdriver tip pushes into easily.
• Discarded wings near lamps, windows or doorways. These come from laron, the flying termites that leave to start new colonies.
• Pellets or fine dust under frames, cupboards or stairs.
• Sagging floors, or boards that flex when you step on them.
• Bubbling paint or a rippled wood surface.
• Fresh patches of filler or new paint on one spot of a frame or floor. Ask what they are covering.
• Sticking doors and windows. The cause may be a frame eaten by termites, damp wood, or a building that has moved.

Where to look

Termites like dark, damp places that nobody touches. Visit in daylight and set aside time just for the ceiling space and the underfloor, because those two are the easiest to skip. Start with:

• Door and window frames, especially the bottom ends near the floor.
• The ceiling space and roof structure. If there is an access hatch, go up with a torch and look for mud tubes on the beams and for leak stains.
• Built-in cupboards and shelving against walls. Open them, empty them as far as you can, and look at the wall behind.
• Timber stairs, especially where the foot of the stairs meets the floor.
• Raised floors and the space underneath. Check the posts, joists and floorboards from below. Watch for wood touching the ground and for standing water under the house.
• Bathrooms and kitchens, around pipes and under sinks.
• The yard, including tree stumps, stacked timber and wooden fences close to the walls.

For the rest of the house, from the roof to the paperwork, use our resale house inspection checklist.

Ulin, other timber and moisture

Ulin, the Bornean ironwood, is very durable and termite resistant. A house with ulin posts and floors starts from a good place.

But not every part of a timber house is ulin. Walls, ceilings, cupboards or extensions may be made of other timber that termites attack more easily. Because ulin is expensive, replacement boards in an older house may not be ulin either. Ask what timber was used for each part, and when each part was built or replaced.

Under the house, galam timber piles (cerucuk) hold up well as long as they stay under water. Wood that goes through repeated wet and dry cycles rots faster.

Moisture is timber’s main enemy. It can come from a leaking roof, seeping pipes, soil touching wood, rain splashing at the foot of the walls, or an underfloor that is always flooded. Damp wood rots and draws termites. Raised houses and their materials are covered in Kalimantan’s raised houses.

Treatment options

If you find termites or rot, these are the options usually offered:

• Soil treatment. A termiticide is put into the soil around and under the building to form a barrier. In an existing house this may mean drilling through the floor and along the base of the walls.
• Baiting. Bait stations are set around the house. Termites carry the slow-acting bait back to the colony. It takes time and needs monitoring.
• Spot treatment, such as injecting wood attacked by drywood termites.
• Replacing damaged wood. Hollowed structural parts such as posts, joists and frames must be replaced once the source of damp is fixed. Use durable or treated timber.

Treatment for subterranean termites should cover the whole building, including the parts you can’t see, because the colony lives in the soil.

Choose a pest control service with a clear address. Ask for a written explanation of the method, the chemicals used, how long the guarantee lasts and when they will re-inspect. If the house uses a well, ask how they keep the chemicals out of the water.

Professional inspection and negotiating

Call in an inspector if damage reaches posts, beams or joists, if you find mud tubes in many places, or if you can’t get into the ceiling space or underfloor. For termites, ask a pest control service to inspect. For damaged structural timber, bring an experienced carpenter or a structural engineer.

Ask for a written report with photos and a repair estimate. That report gives you your firmest ground in negotiation. If the seller won’t allow an inspection, weigh that too.

Your options after that:

• Negotiate the price down by the estimated cost of treatment and repairs.
• Ask the seller to treat the house first before handover, with the guarantee transferred to you.
• Walk away, if the structural damage is too widespread.

Don’t accept a claim that the house “has been sprayed” without a receipt, a report and a guarantee.

Preventing it after you buy

• Keep wood off the ground. No boards, posts or timber stacks touching the soil.
• Clear the underfloor and yard of stumps, offcuts and cardboard.
• Fix leaks in the roof and pipes quickly.
• Keep the space under a raised house dry and airy.
• Inspect regularly, at least once a year before the rainy season, and whenever flying termites appear indoors.
• Use durable or treated timber for repairs.
• Keep receipts and guarantees for every treatment. They help when you sell the house later.

A fuller maintenance guide is in caring for a timber house.

If you are looking for a house, the homes Vorneo is marketing are on our property listings page.