Hygrometers
A hygrometer is the cheapest way to stop guessing. If the number does not fall after you ventilate or run a dehumidifier, the method is not working. These pages cover what to buy and how to read it in a real UK room, not a laboratory.
Key buying considerations
Accuracy to a percentage point matters less than putting one in the room you actually live in.
Put it where you sleep or dry clothes
A meter in the hallway tells you about the hallway. Place it in the bedroom, the drying room, or the worst window.
Relative humidity is not a verdict on mould
Cold walls can still grow mould when the room average looks fine. Use the reading as a trend, not a moral score.
Two cheap meters beat one fancy one
Comparing a drying room with a bedroom is more useful than a single gadget with a smartphone app.
More in Damp & Condensation
Other damp & condensation hubs that sit next to this one.
- Moisture AbsorbersPassive damp traps for wardrobes, cupboards and unheated rooms.
- Window VacuumsWindow vacs for morning condensation on single and older glazing.