How to use a moisture meter to detect damp

Damp is one of the most common yet misunderstood problems in UK homes. It creeps in silently, damages walls, triggers health issues, and often goes unnoticed until it’s too late. That’s where moisture meters come in — an affordable, easy-to-use tool that gives you clarity over hidden moisture and helps prevent mould before it starts.

In this guide, we’ll explain what a moisture meter does, how to use one, and what the results mean for your home.

What is a moisture meter?

A moisture meter is a handheld device that measures the moisture content in building materials such as plaster, wood, concrete, or wallpaper. It gives you a reading as a percentage — the higher the number, the damper the material.

There are two main types:

1. Pin-type meters: These have two metal prongs that you insert into the surface to get a reading. Ideal for timber and plasterboard.
2. Pinless meters: These use sensors to scan the material’s surface without causing damage. Perfect for tiles, wallpaper, or where you want a non-invasive check.

Why use a moisture meter?

Here’s what a moisture meter can help you do:

• Diagnose damp issues early
• Pinpoint problem areas
• Monitor progress
• Avoid costly repairs

How to use a moisture meter (step-by-step)

1. Choose the right meter
2. Turn it on and calibrate
3. Test a ‘dry’ area first
4. Test suspect areas
5. Record your readings

What’s a normal moisture reading?

• Plaster: 0–15% (Safe)
• Wood: 6–15% (Safe)
• Walls >18%: Investigate
• Any reading >20%: Act fast

What if the reading is high?

Don’t panic — high moisture doesn’t always mean mould. But it is a warning.

- Investigate further
- Try again in dry vs. wet weather
- Ventilate & monitor
- Still high? Consult a mould expert or use our Mould Protocol

Recommended moisture meters (uk market)

1. Protimeter Mini
2. Dryzone Moisture Meter Detector
3. Trotec BM31

Final thoughts

A moisture meter is your first line of defence against invisible damp. Whether you’re renting, renovating, or just keeping your home healthy, it’s a smart investment.

Don’t wait for black mould to show up — check now, treat early, and breathe easier.