What is Relative Humidity?
The amount of water vapour present in air expressed as a percentage of the amount needed for saturation at the same temperature.
How does Relative Humidity affect Hardwood Flooring?
Wood is a Hygroscopic material, meaning that it always contains water. Wood is constantly exchanging water vapour with the ambient air around it and always seeking to be in balance with its surroundings. When humidity is high, wood will swell and when humidity levels are low, wood will shrink.
An easy way to picture this is think of ordinary dish sponge. When the sponge is wet and saturated it will be heavy and swell. When it is dry it will reduce in size. Because this constant change between swelling and shrinking will damage the wood, it is imperative to keep wood in a stable and controlled environment.
Common Problems with floors when relative humidity is not in the optimal range
Buckling, Cupping, Crowning, Gapping, Checking and Squeaking/Crackling noisy floors. Below is a picture of checking within wood flooring.
Superior’s recommended Relative Humidity levels
How do different regions and seasons react to relative humidity?
Humidity will be different throughout various geographic regions, times of year, and weather conditions. For example, in Southern Ontario, where our headquarters are located, we experience high humidity in our summer season which will cause concerns such as cupping or a squeaking/crackling noisy floor. However, drier regions, such as Arizona will have a very low humidity level in the air and may experience checking or gapping.
Forced air systems can also cause your floor to dry out quicker after experiencing a period of time with higher humidity, which may also cause checking and gapping.
Be aware of the indoor humidity level in your home and maintain a constant and stable environment all year round to enhance the longevity of your flooring.
How Relative Humidity affects your family’s health.
Not only does Relative Humidity have an effect on your wood floor, but it can also be damaging to the overall health of everyone in your household. The below chart shows at which Relative Humidity levels you may experience bacteria, dust mites, allergies, etc.
The good news is that when you keep your home’s relative humidity levels in the optimum zone to ensure a healthy living environment for your family, you will also be keeping the conditions ideal for your floor to also enjoy a long and healthy life.