Why has my new building gone grey?

Almost certainly nothing is wrong. Untreated and lightly treated timber turns silver-grey in sunlight. It's UV bleaching the surface of the wood, and it's cosmetic — not rot, not a fault, and not a sign the building is failing.

It can start within a few months, and it's usually uneven at first, which is what makes people worry.

How to tell it's fine

Silvering is surface-level and uniform in texture. Press it — it should be firm. Rot is soft, often darker, smells musty, and appears in specific places: the bottom of panels, around fixings, where water collects, where timber touches the ground.

If it's grey but hard, it's weathering. If it's soft or crumbling, that's different and worth a photo to us.

If you don't like the look

• Clean it. A stiff brush and a proprietary timber cleaner lifts most of the greying.
• Then treat it. A coat of preservative or a UV-protective finish restores the colour and slows it happening again.
• Repeat as needed. Anything facing south will go first and go fastest.

If you don't mind it

Plenty of people like the weathered look and leave it. That's a perfectly reasonable choice — but don't confuse "I like the grey" with "I don't need to treat it."

If your building is dip-treated or untreated, the preservative still needs renewing on schedule whatever colour you want it to be. The colour is cosmetic; the preservative is structural.

Pressure-treated timber will also silver over time. That's just the surface — the protection is inside the wood and is unaffected.

Send us a photo if you're unsure. We'd much rather tell you it's fine than have you worry about it.