Solid wood flooring, as the name suggests is made from a 100% natural product, wood. Like all natural materials, wood responds to changes in temperature and humidity in the atmosphere around it. Wood typically responds to these atmospheric changes by expanding and contracting. When there is excess moisture in the air, wood will draw up some of that moisture and expand and then when the humidity levels are reduced, the wood will then release the moisture held in its structure and contract. Although this is a natural process and at average levels should not pose any problem to the wood, when the levels become extreme, problems can occur.
In a natural setting, for example in a forest, humidity and temperatures change according to the season as well as the weather on any given day. Once wood is brought into the home, although it is protected from the vagaries of nature, it is then subjected to the fluctuations in temperature and moisture that we choose to throw at it throughout our day to day lives.
During winter months, wooden floors which are installed in centrally heated homes are likely to lose moisture and contract. This contraction is caused by the dryness of the air, encouraging the wood to naturally lose its inherent moisture. The contraction which occurs in the wood during these winter months is highly likely to cause gaps to appear in the floor, which, if not properly insulated may give rise to draughts.
Of course the opposite becomes true as the weather starts to improve and the heating is switched off. The switching off of the central heating in the home and the rise in natural temperatures which signify the coming of summer means more moisture in the air, some of which will be absorbed by the floor causing slight expansion of the boards. Under normal circumstances, this will result in the closing of the gaps which appeared during the drier winter months.
This natural process of expansion and contraction is unlikely to pose any sort of damage or distortion to your solid wood floor. In fact, moisture levels of anywhere between 45 and 60% should not have any detrimental affect on the stability or look of your floor. That said, humidity which is significantly above this level could, if left unattended, cause the wood to rise in the middle of each plank as well as giving rise to inherent gaps. This distortion may prove temporary and in the industry is termed ‘cupping’. Wood which remains cupped after humidity levels have dropped again may need to be sanded to regain its level appearance.
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FAQ
1. How does humidity affect solid wood flooring?
Solid wood flooring responds to changes in temperature and humidity by expanding and contracting. Excess moisture in the air causes the wood to absorb some of that moisture and expand. When humidity levels are reduced, the wood releases the moisture and contracts.
2. What happens to wood flooring during winter months in a centrally heated home?
During winter months, wooden floors in centrally heated homes are likely to lose moisture and contract. This contraction is caused by the dryness of the air, encouraging the wood to naturally lose its inherent moisture. This contraction may cause gaps to appear in the floor.
3. What changes can be observed in wood flooring as weather conditions improve and heating is switched off?
As the weather improves and central heating is switched off, the rise in natural temperatures means there’s more moisture in the air. Some of this moisture will be absorbed by the floor, causing slight expansion of the boards. This usually results in the closing of the gaps which appeared during the drier winter months.
4. What is the acceptable range of humidity for solid wood flooring?
The acceptable range of humidity for solid wood flooring is anywhere between 45% and 60%. Humidity levels within this range should not have any detrimental effect on the stability or look of the floor.
5. What happens if humidity levels are significantly above the acceptable range for solid wood flooring?
If humidity levels are significantly above the acceptable range, it could cause the wood to rise in the middle of each plank and create inherent gaps. This distortion, termed ‘cupping’ in the industry, may be temporary. If the wood remains cupped after humidity levels drop again, the floor may need to be sanded to regain its level appearance.