The best termite protection for a new building in Tanzania happens before the floor slab is cast: clear the plot of anthills, roots and timber, treat the soil under and around the foundations with a registered termiticide, use treated or naturally resistant timber, and leave no wooden formwork or pegs buried in the ground. Termites (mchwa) live in the soil and can climb through a hairline crack in the slab, so it is far cheaper to stop them at the start than to fight them once they reach your roof timbers and door frames.
Why are termites such a problem in Tanzania?
Subterranean termites are found in most of the country, and the warm climate keeps them active all year. They eat cellulose, which means timber, ceiling boards, paper, cardboard and even the paper facing on some gypsum boards. They work hidden inside the wood, so by the time you see damage, a roof truss or door frame may already be hollow.
Termites usually enter a house from below. They build mud tubes up foundation walls, through cracks in the slab, around pipes that pass through the floor, and along the gap where the floor meets the wall.
How do you protect a new building from termites?
- Clear the site properly. Dig out anthills completely, including the queen chamber, which can sit well below ground. Remove tree stumps and roots, and do not bury any wood or vegetation in the fill.
- Treat the soil. After the foundation trenches are dug and again after the hardcore is compacted, a trained applicator sprays a registered termiticide over the soil at the rate on the label. This creates a treated layer the termites will not cross. Treat along the outside of the foundation walls too.
- Protect the treated layer. Lay the damp-proof membrane over the treated hardcore straight away and do not dig through it again. Every new trench for a pipe breaks the barrier.
- Seal penetrations. Pipes and cables that pass through the slab should be well bedded in concrete with no gaps around them.
- Clean up formwork. Pull out every timber peg, stake and offcut before backfilling. A forgotten piece of wood under a slab is a termite feeding station.
- Use the right timber. Use pressure-treated timber for roof trusses, purlins and door frames, or naturally resistant hardwoods. Untreated softwood in a roof is an invitation.
Which chemicals are used for termite treatment?
Soil treatment products in Tanzania must be registered for use. In practice, contractors use registered pre-construction termiticides, mixed and applied by trained staff at the dose on the label. Ask your contractor which product is being used and ask to see the label. Avoid old, banned persistent chemicals that some sellers still offer cheaply; they are dangerous to people and to ground water, especially if you have a borehole on the plot.
| Method | When | How long it lasts | Notes |
|---|---|---|---|
| Pre-construction soil treatment | Before the slab | Many years, depending on product | The most effective and cheapest stage |
| Treated timber | During roofing and joinery | Life of the timber if kept dry | Cut ends need brushing with preservative |
| Physical barriers (mesh, graded stone) | Before the slab | Long life | Less common in Tanzania, specialist work |
| Post-construction treatment | After termites appear | Varies | Drilling the slab, injecting chemicals, baits |
| Bait stations | After construction | Ongoing monitoring | Useful as a check and for colonies near the house |
How much does termite treatment cost?
As an example, pre-construction soil treatment for a typical family house in 2026 costs somewhere around TSh 300,000 to 1,000,000, depending on the footprint and the product. Treating an existing house after termites have moved in is usually several times more expensive, and that is before repairing the damaged timber. Prices are rough examples only. The treatment is a small line in your bill of quantities, so check it is there.
What should I check after moving in?
- Walk around the outside of the house every few months and look for mud tubes on the walls and plinth.
- Keep firewood, timber and cardboard away from the walls.
- Do not let soil, flower beds or mulch build up against the walls above the plinth.
- Fix leaks quickly. Termites like damp timber.
- Check the roof space and door frames once a year, or add it to your home maintenance calendar.
Frequently asked questions
Do concrete houses still get termites?
Yes. Termites cannot eat concrete, but they come through cracks and gaps to reach timber roofs, door frames, ceilings, furniture and stored paper.
How long does termite soil treatment last?
It depends on the product and the soil, typically many years. It lasts longest when the treated layer is never disturbed after the slab is cast.
Is it safe to live in a house treated for termites?
Pre-construction treatment sits under the slab and away from living spaces. Use only registered products, applied by trained people at the label dose.
Are steel roof trusses better against termites?
Steel trusses are not eaten by termites, which is one reason they are popular. You still need to protect door frames, ceilings and other timber.
Build it right from the ground
Vika Construction includes site clearing and soil treatment in its foundation work. Talk to us about your new house.
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