The heart of winter will often bring out gaps in hardwood floors. Even floors that are professionally installed by the best flooring companies are going to see some gapping. This issue can vary from climate to climate in it’s severity and consistency. In this article we will address why gaps in hardwood floors show up and how they can be dealt with before and after hardwood floor installation. The reason for gaps comes down to few different issues: (1.) the type of wood you use, (2.) the species of wood you use, (3.) the size of wood planks that are being installed and (4.) the amount of relative humidity (RH) in your home.
I. Different Types of Flooring
While engineered flooring is designed and is expected to be more stable than solid wood, sometimes this doesn’t matter. Several manufacturers require that their engineered floors only be installed in a certain Relative Humidity range. If your home’s RH range is outside of their specified range, their warranties can be void. Therefore, engineered flooring may be an option just be sure to check the manufactures warranty prior to installation.
With real hardwood floors the chance for fluctuations within the floor are greater than engineered flooring. Wood is porous and will expand and contract more depending on the amount of moisture in the air. Just like expensive, high-end guitars must be kept in environments where the RH is ideal, real wood floors need the right environment.
II. Choosing The Right Species of Wood
There are various species of wood that are more stable than others. For example, a plank of hickory wood will shrink more than a red oak plank because red oak has a smaller dimensional change coefficient. This simply means that red oak a lower tendency to shrink and expand compared to hickory. Woods with a smaller dimensional change coefficient (oaks & cherry woods) are less likely to contract and expand than others. The way the real wood is cut also has an affect on the moisture change. Woods that are quarter sawn shrink roughly half as much as wood that is flat sawn. Therefore, hardwood floors that are quarter sawn are going to see less gapping than flat sawn wood floors.
III. Gaps in Hardwood Floors Are Worse in Larger Planks
The size of the wood planks in your home also make a difference in the amount gapping in your hardwood floors. Narrower boards such at 2¼ inch-wide planks will expand and contract 50% less than a 5 inch-wide plank in the same species of wood. Therefore, you can expect the gaps in 5 inch-wide floors to have gaps that are twice big as the gaps associated with 2¼ inch-wide planks. Larger planks mean more ability to retain or lose moisture.
IV. The Amount of Moisture in Your Home
Another factor affecting gaps in hardwood floors is the amount of moisture in your home. Addressing Relative Humidity (RH) in your home can have a significant impact in keeping your floors in top shape, if it is done well. The drying out of the wood during winter is what ultimately causes the wood to shrink. During the summer months, humidity is usually at a year round high which allows plenty of moisture to help the wood. The trick is to have just enough RH during the winter months without putting too much moisture in your home. This is done with humidifiers that can be purchased at Lowes, Home Depot or other retail stores.
To avoid gaps in your hardwood floors, be sure to choose the right kind of wood, the right species of wood, the right size of wood and to make sure you have the right amount of moisture (RH) in your home. You can probably never completely avoid gaps in your hardwoods floors, but with proper selection and maintenance, you can have the beautiful hardwood floors that your home deserves.