Dry Rot and Damp Treatment
Woodworm rarely travels alone. Find the damp first, because it feeds beetle and rot alike.
- Learn dry rot from wet rot
- See how damp is found and fixed
- Ask for a survey that checks both
Damp lets woodworm and rot take hold
Wood-boring beetles and fungi both prefer timber that stays damp. If you find one, check for the other. Treating the insects while a leak continues rarely works, because new damp wood invites them back.
Timber that stays above roughly 20% moisture content is at risk of decay. Dry wood is much safer. For that reason, a good survey includes a moisture reading as well as a look for holes.
Dry rot and wet rot are not the same
Dry rot
Dry rot (Serpula lacrymans) can spread through masonry and across timber. It leaves cracked, cube-like wood, a musty smell and rusty spore dust. It is the more serious of the two.
Wet rot
Wet rot needs a constant source of water, so it stays near the leak. It leaves dark, soft wood that cracks along the grain. It is usually easier to contain.
Find the damp, treat the decay, stop the return
- 1
Find the moisture
A surveyor uses a meter and checks gutters, roofs, pipes and ground levels. They trace the source, not only the symptom.
- 2
Stop the water
Repair the leak, clear the drain or improve the ventilation. Without this, nothing else lasts.
- 3
Remove and treat
Cut out badly decayed wood and treat the sound wood nearby. Specialists also treat masonry where dry rot has spread.
- 4
Treat the beetle
If beetle is present, use the right treatment method for the timber. Then keep the area dry and ventilated.
Where to read next
Our guide to woodworm vs dry rot shows how to tell the two apart. The page on woodworm vs wet rot does the same for wet rot. If you are unsure what you have, request a survey, because it checks for both.
Dry rot and damp: your questions
Can woodworm and dry rot occur together?
Yes, because both like damp timber. A survey checks for both. Treat the cause of the damp first.
How do I spot dry rot?
Look for cracked, cube-like wood, grey strands, a mushroom smell and rusty dust. Read woodworm vs dry rot.
Does fixing damp kill woodworm?
It stops new attacks and may let a colony fade, but active beetle may still need treatment. A surveyor will say which.
Who should treat rot?
Choose a specialist with experience of rot and damp. Ask for a written scope. See costs for price context.
Damp, rot or woodworm?
Send your postcode and what you have seen, because one survey can check all three. A local specialist will call you.