When Can You Use Lumber That Has Been Stored Outside (and When Not)
If you have a home project that takes time, it’s likely that you’ve thought about saving space by storing lumber outdoors. This may seem like a good way to alleviate the clutter caused by home improvement projects, but it’s not always a good idea. Here’s when it’s normal and when it’s not, and how to determine damage from improperly storing lumber.
It depends on what you plan to do with your lumber.
If your lumber is for a garden trellis, a small personal project, or something that doesn’t carry a load, you don’t have to worry so much about storing your lumber outdoors. Any damage you find will be annoying but not dangerous, so be prepared to accept some imperfections. If you’re building a deck or framing a new bathtub, you’ll need to make sure your lumber is in good enough shape to maintain its rating and be safe to support the weight of whatever will sit on it. In this type of application, safety first is the best watchword.
It depends on what kind of lumber it is
In general, plywood and many types of composite lumber, made by compressing multiple layers of wood and using glue to glue them together into a sheet or stick, do not withstand prolonged exposure to moisture. Because different layers of wood will expand and contract with changes in humidity and temperature at different rates and in opposite directions, exposure to the elements can cause this type of lumber to disintegrate and bubble, compromising its structural integrity. However, solid wood, such as two-by-fours, can withstand the elements a little better because it is made from a single tree that basically expands and contracts at the same time, causing it less damage as temperature and humidity changes.
Dry it first
If you have a pile of lumber that has been stored outdoors, chances are it has gotten wet. To assess whether it is safe to use, you should dry it before doing anything else. Expose the lumber to the sun for a few hours, rotating it so it gets full sun from all angles, and look for any signs of rot as you go. If sunlight is not an option, you can spread it out in the garage or home store with a fan or even a heater to dry it out. If the wood is slippery, has soft spots, or is severely discolored, you may not be able to salvage it—these are signs of mold and rot.
Clean up
Once the lumber is dry, it should be cleaned with a rag. Wipe off dirt, bugs and other debris and evaluate the surface. If you notice splits deeper than 16 to 8 inches, the lumber can no longer be used for construction purposes, but you can still save it for use in less risky applications, such as building shop furniture. If there are small scars on the surface of the wood, you can sand it with a light sand to remove splinters. You should also look for small holes and accumulations of sawdust without any indication that it came from tools. Both can be signs of insect damage; if they are found, it is time to take these boards out of service.
Take section
If you can’t tell how damaged your boards are, you can get a better look by cutting one open and seeing what it looks like on the inside. If you cut into it and see insect tunnels or rot, you should remove them. If it looks durable, you can add it to your checklist of lumber that can probably be saved.
Compare it to a new piece of wood.
If you have a sample of new, undamaged wood that you want to use, you can compare the characteristics of your old, weather-worn boards with the newer ones to see if they are similar. The lumber should be the same size and shape as its new counterpart and have approximately the same hardness. Once dry, it should feel like it will be about the same weight.