Whether you live in the desert or receive hundreds of rainy, foggy days per year, it is a good idea to monitor humidity levels in your home. Excess humidity can make your home a breeding ground for mould and cause damage to wood and appliances. Humidity that closely matches the humidity outside on a daily basis may indicate poor home insulation. Fortunately, it is easy to test for relative humidity at home. In order to monitor the humidity, simply purchase a hygrometer and walk around your house with it.
Walk through your home and consider the best approach to monitoring humidity. If you think you may have a humidity problem, you should test the humidity in each room regularly. If you are merely curious, you may choose to monitor the humidity only once and in only one room.
Purchase a hygrometer that suits your needs. Digital handheld hygrometers can be carried from room to room and they record a humidity reading almost instantly. Decorative hygrometers can be hung on walls and are suitable for long-term humidity measurement.
Write down the relative humidity in each room of your house. Average the totals to find the average humidity for your entire house.
Call the National Weather Service or check current weather conditions to find the most up-to-date relative humidity outside of your house.
Compare the readings from your hygrometer to the relative humidity outside. According to USA Today, indoor relative humidity should ideally be between 30% and 50%.
Keep in mind that outdoor humidity levels can vary drastically from day to day. Read the instructions carefully on your hygrometer. It may need to be calibrated annually.