Static reference chart

Target humidity chart UK

Relative humidity changes with temperature, weather and household activity. This chart gives a practical target range for homes dealing with condensation, musty smells, mould risk or indoor laundry.

Quick takeaway

Aim for roughly 40–60% RH

Brief spikes after showers or cooking are normal. The problem is humidity that stays high for hours, especially near cold windows, wardrobes and external walls.

Track it for 7 days

30–40%Dry

40–60%Target

60–65%Watch

65%+Risk if persistent

ReadingWhat it suggestsWhat to do

30–40%Often dryAvoid over-drying; check comfort, skin/eyes and ventilation.

40–60%Normal target zoneGood practical aim for many UK/Irish homes.

60–65%Watch zoneImprove ventilation, reduce moisture sources and monitor trends.

65–70%Mould-risk zone if persistentUse checklist, check cold surfaces and consider dehumidification.

70%+High humidityAct quickly; look for leaks, wet laundry, poor extraction or damp sources.

How to measure properly

Use a hygrometer: do not rely on how the room feels.
Measure for several days: one reading after a shower or cooking session can mislead.
Check cold spots: wardrobes, window reveals and external walls may be worse than the centre of the room.
Track after laundry: indoor drying can keep humidity high long after clothes feel nearly dry.

If readings stay high

Use the checklist to reduce avoidable moisture first. If humidity still sits above the target range, compare dehumidifier size and running cost before buying.

Check size chart Choose a hygrometer