What do termites eat, and what does that mean for your house?
Termites eat anything built from plant fibre. The useful question is not what they like but what in your house they can reach.
The short answer: cellulose
Termites eat cellulose, the fibre that makes up the walls of plant cells. Timber is the obvious source. Paper, cardboard, books, fabric made from plant fibre, dead leaves, roots and mulch all contain it too.
They cannot digest it alone. Microbes living in a termite's gut do the breaking down, which is why the insect can live on a diet that would starve most animals.
What they go for inside a house
Termites do not pick the tastiest board. They follow moisture, warmth and shelter, and they eat what they meet along the way. Still, some timber is easier to eat than others.
- Softwood and sapwood have little natural durability and go first.
- Springwood, the softer growth band in each ring, is often eaten before the harder band, which is why damaged timber can look layered.
- Damp or decayed timber is easier to enter, and a leak can make a sound board attractive.
- Paper and cardboard stored against a wall or on a slab are a common secondary target.
What they can tunnel through but cannot eat
People are often told termites eat plaster, insulation or plastic. They do not. They tunnel through or over soft materials to reach timber, and they build mud tubes across surfaces they cannot chew. That is why a house can show damage in a place with no food in sight.
| Material | Do termites eat it? | What they do with it |
|---|---|---|
| Softwood framing | Yes | Hollow it from the inside, leaving a thin skin |
| Hardwood heartwood | Slowly, and species vary | Often avoided, but the sapwood next to it is not |
| Paper, cardboard, books | Yes | Eat through stored items touching walls or floors |
| Plasterboard paper face | The paper, yes | Strip it, leaving the gypsum core |
| Concrete, brick, steel | No | Tube over them or enter through gaps |
Why this changes where you look
Because they eat cellulose wherever they find it, damage is often not where the termites came in. They can enter at a slab edge and eat a door frame two rooms away. How termites get into a house lists the routes they use.
It also means the contents of your house are food. Stored boxes, timber offcuts and firewood against a wall give a colony a reason to stay near the building. Moving them is a sensible habit, and what attracts termites covers the rest.
Does timber type protect you?
Only partly. A durable species or a treated board slows the damage in that board, and it does not make the house safe. Termite resistant timber explains what the ratings really cover and why sapwood is the catch.
Whatever the timber, resistant is never a substitute for a management system and regular inspection.
If you see them eating
If you find termites feeding on something, do not poke at the timber or spray it. Spraying drives the colony away from that spot and back into the structure, out of sight. Take a photo, leave the area alone and book a licensed timber pest inspection.
Leave identifying the species to the inspector too. It is done with soldiers under magnification, not from a photo, and the answer changes what treatment is used.
Frequently asked questions
Do termites eat only wood?
No. They eat any plant fibre made of cellulose, including paper, cardboard, fabric from plant fibre and leaf litter. Timber matters most because it is what holds a house up.
Do termites eat concrete, brick or steel?
No. They cannot eat these materials. They build mud tubes over them or find gaps and cracks to reach the timber behind.
Do termites prefer new or old timber?
Species and moisture matter more than age. Sound, dry heartwood of a durable species is eaten slowly, while damp softwood and sapwood go first, whether the board is new or old.
Sources
What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.
- Standards Australia. Australian Standards (AS 3660 termite management, AS 4349.3 timber pest inspection)
- Queensland Building and Construction Commission. Protect against termites — termite management systems and inspections