Swollen Doors & Humidity: Why It Happens & How to Fix It
Picture this: you’ve just finished remodeling your home. You have updated the appliances, wall finishes, baseboard, crown, casing, windows, doors, everything. Tons of money, tons of time, all to make your home more beautiful and more valuable. Now picture this: you’re drinking your morning coffee, and you notice that a piece of your brand-new baseboard is twisting and pulling away from the wall. Concerned, you check some of your other renovations. You are shocked to find the same things happening in all the rooms of your house, to your baseboard, crown molding, door casing, and your new hardwood doors! What is happening?!
To answer this question, we need to talk about wood. Wood is a natural resource that absorbs and releases water to be in balance with the environment around it. Because of this, wood tends to expand as it gains moisture, and shrink as it releases moisture. Any solid wood product will expand and contract over time, to keep in balance with the surrounding environment. The result is a swollen door that may cause you headaches. Finishing the wood and sealing the grain, via a stain and top coat, or priming and painting, does not make the wood impervious to these effects, it only minimizes the process.
Wood products in very humid areas, specifically doors, are especially susceptible to swelling, since there is more moisture in the air. The wood will absorb this extra moisture, causing it to swell. In these types of cases, swollen wood doors may become difficult to open, or not open at all. In the most extreme cases, there will be so much moisture that the glue that holds the product together will soften, and the door will push itself apart.
In very dry areas, the exact opposite is true. When the environment is dry, the wood will release its moisture, and shrink in size. This can cause the panels in a door to shrink, showing small amounts of unfinished wood. Additionally, doors that are in very dry environments will show gaps in the joints where the parts of the door have pulled themselves apart. This can also cause wood trim to twist, warp, and sometimes crack. During winter months in the colder parts of the world, doors and other woodworking will shrink due to the dry heat provided by home heating units. This type of contraction can also be caused by over-use of dehumidifying units in homes.
How do we fix this problem? Humidity is the key to protecting your doors and other woodworking. Many modern homes have dehumidifying units as part of their home HVAC system. It is critical to your woodworking not to dry the house out too much. An ideal humidity for most woodworking is between 40 and 60 percent. If this sounds high, bear in mind that the relative humidity in the Sahara Desert is near 25%, and many modern homes are considerably less than this. Typically, if the humidity is right, your doors and other woodworking will correct themselves with time. However, doors and other woodworking that are consistently subjected to extremes of humidity may not ever correct themselves.
Here at Allegheny Woodworks, we have our doors and trim in every environment imaginable. We have doors in every state, including Alaska and Hawaii, Mexico, Israel, Canada, China, Ireland, and Puerto Rico. In twenty years of manufacturing doors and wood products, we have learned the effects of moisture on wood products. Our door warranty includes some great guidelines on protecting doors and trim from humidity, and the problems that it causes. However, the wood that we use is the same as the wood that is used in any other wood product, so feel free to apply that information to any of your wood products. Proper protection from Mother Nature can protect all your woodworking for years to come.
