You have invested in reclaimed lumber — perhaps a load of century-old heart pine joists or a stack of weathered oak barn boards. The wood survived a hundred years inside its original structure, but it can deteriorate surprisingly fast if stored incorrectly after salvage. At Houston Lumber, we process and store thousands of board feet of reclaimed material at any given time, and proper storage practices are fundamental to preserving quality.
Moisture Is the Enemy
The single biggest threat to stored lumber is uncontrolled moisture. Wood is hygroscopic — it absorbs and releases moisture depending on its environment. Reclaimed lumber that has been kiln dried to 8–12% moisture content will re-absorb water if stored in a damp environment, leading to swelling, warping, and eventually mold or fungal decay. The ideal storage environment maintains relative humidity between 30% and 50%.
If outdoor storage is unavoidable, elevate the stack at least six inches off the ground using concrete blocks or pressure-treated runners. Cover the top with a tarp or metal roofing, but leave the sides open for airflow. A completely sealed tarp traps moisture underneath and accelerates mold growth — the opposite of what you want.
Stickering: The Non-Negotiable Step
Every layer of stacked lumber must be separated by stickers — uniform strips of dry wood (typically 3/4" × 1-1/2") placed perpendicular to the boards at 16- to 24-inch intervals. Stickers allow air to circulate between layers, promoting even drying and preventing the boards from cupping or staining where they contact each other. Stickers should be aligned vertically from layer to layer to distribute weight evenly and prevent bowing.
Use dry, clean hardwood for stickers. Avoid green wood or softwood species that might bleed sap or transfer stains. Poplar and oak make excellent sticker material. Replace any stickers that show signs of mold immediately.
Flat, Level Surface
The foundation of your stack matters more than most people realize. A stack built on uneven ground will introduce twist and bow into boards that were perfectly straight when they arrived. Use a level surface — a concrete slab is ideal — and verify that your base runners are co-planar before stacking. Weight the top of the stack with heavy, flat material to apply even downward pressure, which helps keep boards flat as they acclimate.
For long-term storage exceeding three months, inspect the stack monthly for signs of insect activity, mold, or shifting. Reclaimed wood that has been properly processed and kiln dried is resistant to insects, but damp conditions can invite new infestations. Address any problems immediately — a small patch of mold spreads fast in a tight lumber stack.