A healthy humidity level in the home is usually between 40 and 60 percent relative humidity, with 45 to 55 percent being a comfortable average. Below that, the air quickly becomes dry; above that, condensation, mold, and dust mites have a better chance of thriving. Measuring with a hygrometer is the only way to be certain.
What is relative humidity?
Relative humidity (RH) indicates the amount of water vapor the air contains compared to the maximum it can hold at that temperature. Warm air can hold more moisture than cold air. This is why RH rises when a room cools down and falls when you heat it. The aforementioned range of 40 to 60 percent is a general guideline and not a legal standard; some sources mention slightly different limits.
What happens when humidity is too low?
If the RH drops below approximately 30 to 35 percent for an extended period, often in winter, many people notice dry skin and lips, irritated eyes or a dry throat, and more static electricity. Wooden furniture and floors may shrink or creak. Symptoms vary from person to person; if you continue to suffer, speak to your doctor.
What happens when humidity is too high?
If the RH is structurally above 60 to 65 percent, condensation forms on cool surfaces. Mold and dust mites thrive in damp conditions, which increases the risk of musty odors and damp patches. In people sensitive to dust mites, high humidity can worsen symptoms, but an appliance is no substitute for medical advice. You can read more about condensation in Can a dehumidifier prevent condensation on windows?.
How do you measure humidity?
Use a hygrometer, often combined with a thermometer. Do not place it in the sun, next to a heater, or near an open window. Do not look at a single moment but at the trend over a few days, for example, in the morning and evening. Measure in the room where you suspect the problem, such as the bedroom, bathroom, or basement.
How can you make adjustments?
| Situation | What helps |
|---|---|
| RH below 40 percent | Lower the heating, dry laundry indoors, plants, a humidifier |
| RH between 40 and 60 percent | Nothing; keep ventilating |
| RH above 60 percent | Ventilate more, use a lid on the pan, dehumidifier |
| Damp patches and mold | Trace the cause, clean, limit moisture |
Ventilation remains the foundation: short and intensive airing removes moisture. If that is not enough, for example in a basement or a room without a window, a dehumidifier can help. Read Does a dehumidifier help against mold? and What humidity level do you set on a dehumidifier?. Dynter does not sell humidifiers; for those, you should look for a device intended for that purpose.
Quick answer: a healthy humidity in the home is between 40 and 60 percent. Below 30 to 35 percent it becomes too dry, above 60 to 65 percent the risk of condensation and mold increases.
Highlighted: the AirPure DH251 dehumidifier
The Dynter DH251 is a dehumidifier for rooms with too much moisture.
Dehumidification: up to 900 ml per day
Water tank: 3800 ml, with safety sensor that switches off when the tank is full
Suitable for: rooms up to 55 m²
Energy consumption: 80 W
Extras: timer function from 1 to 24 hours, night mode that turns off the display
The product page does not mention an adjustable target humidity. Therefore, use a separate hygrometer to determine how long the device should run.
View the Dynter DH251 or the collection of dehumidifiers. You can read exactly what a humidistat does in What is a humidistat and how do you use it?.
Frequently asked questions
What is the ideal humidity in the bedroom?
40 to 60 percent is a good guideline there too. Measure at night and in the morning to see if condensation is forming.
Is 70 percent humidity too high?
If it is structural, yes: it increases the chance of condensation and mold. Ventilate and consider a dehumidifier.
Is 30 percent humidity too low?
That is on the low side and can cause dry skin and a dry throat, especially in winter.
How do I prevent condensation on windows?
Ventilate, keep the humidity low, and avoid cold spots as much as possible.
Do I need a hygrometer?
It is the easiest way to measure what is going on. Guessing does not work well.