Woodworm in West Midlands Period Homes: Active or Old? A Survey Guide

Open up a loft hatch or pull back a rug in almost any Victorian or pre-war West Midlands property and you'll find them — those neat little 1–2 mm round holes peppering the joists and floorboards. The instinctive reaction is to panic and reach for the phone, but the truth is more nuanced: most of those holes are decades old and the beetles are long gone.

Knowing whether you have active woodworm or historic damage decides whether you spend £400 on a survey-led spot treatment or £3,000 on a full timber spray. Here's how a competent surveyor — and you — can tell.

What 'woodworm' actually is

Woodworm isn't a worm at all — it's the larval stage of several wood-boring beetles. The larvae hatch from eggs laid in cracks in timber, tunnel through the wood for 2–5 years eating cellulose, then pupate and chew their way out as adult beetles. That exit is the hole you see.

So a hole only tells you a beetle once left. The real question is: when?

The four species you'll meet in the West Midlands

Treatment, urgency and price depend heavily on species. A surveyor should identify which one before quoting.

Common furniture beetle (Anobium punctatum): 1.5–2 mm round holes, by far the most common. Prefers damp sapwood. Usually a slow problem.
Deathwatch beetle (Xestobium rufovillosum): 3 mm holes, typically in old oak and softwood with some decay. Mainly a structural concern in churches and historic timber-framed buildings — fairly common in rural Worcestershire, Staffordshire and Shropshire.
House longhorn (Hylotrupes bajulus): oval 6–10 mm holes in softwood roof timbers. Rare but serious — has been found in pockets of the Midlands and triggers full structural treatment.
Powderpost beetle (Lyctus brunneus): 1–2 mm holes specifically in the sapwood of hardwoods like oak and ash. Often comes in with new flooring or imported timber.

Active vs historic — how to tell

This is the single most important diagnosis, and you can do a lot of it yourself with a torch.

Holes look pale, fresh and clean inside — likely active. Dark, dusty, weathered holes that match the surrounding wood colour — likely historic.
Fine, pale powdery 'frass' (bore dust) on or below the timber, not just sitting in old cobwebs — almost certainly active.
Live or dead adult beetles found on windowsills or in light fittings between May and September — strong evidence of an active emergence.
Tape test: cover suspect holes with masking tape, leave for a few weeks during summer. Fresh holes appearing in the tape = active.

What drives an infestation

Wood-boring beetles need moisture. Common furniture beetle thrives at timber moisture content above 12% — which in the West Midlands you'll get in unventilated cellars, under suspended ground floors with blocked airbricks, in lofts with condensation issues, and around any leak.

Fix the damp and you'll often kill the infestation without ever spraying a thing. This is why a good surveyor opens with a damp meter, not a quote.

Treatment options and rough West Midlands pricing

Realistic 2026 prices for a typical 3-bed period property:

Survey and written report: £150–£300, often deducted from any subsequent treatment.
Spot treatment of a single affected area (e.g. one section of floor joists): £350–£700.
Whole-roof timber spray with permethrin-based treatment: £900–£2,200 depending on access and m².
Structural repair or splicing in new timber where load-bearing beams are weakened: priced separately — get a structural engineer's opinion first.
Heat treatment of furniture or movable items: £200–£500 per chamber load.

When you genuinely need a professional

DIY woodworm sprays are widely sold but rarely the right answer for anything beyond a single piece of furniture. Call a surveyor if you have:

Fresh frass appearing on shelves, beams or under floorboards.
Holes larger than 3 mm (suggesting deathwatch or longhorn).
Visible weakening, sagging or springiness in joists.
An upcoming house sale or mortgage application — lenders increasingly ask for a recent timber report on older properties.
Damp issues you can't resolve yourself.

Frequently asked questions

I've just bought a Victorian house with lots of woodworm holes — should I worry?

Not yet. Most of those holes are likely historic. Get a CSRT- or PCA-qualified surveyor in for an independent inspection (not a free quote from a treatment company) — they'll tell you what's active and what isn't.

Are modern woodworm treatments safe for pets and children?

Yes, once dry. Permethrin-based treatments are low-toxicity to mammals when used as directed. You'll typically need to vacate treated rooms for a few hours and ventilate well.

Will treatment damage exposed oak beams?

Modern micro-emulsion treatments are clear and don't significantly alter the appearance of bare oak. If beams are waxed or oiled, that finish may need stripping back first — discuss with your surveyor.