The number one misconception about lumber is that pressure treated lumber, cedar, and redwood are maintenance-free; however, no wood is maintenance-free. All pressure treated wood, cedar, and redwood are susceptible to damage from sunlight, rain, and snow. Pressure treated lumber does come with a lifetime warranty against rot, decay, and termite damage, but pressure treatment does not protect against weathering cycles of wetting and drying. The elements can cause wood to check, crack, and splinter over time.
Recommendations:
- Butt deck boards tightly together during installation, unless using Dried After Treatment lumber.
- Use a good quality non-corrosive deck screw. The hold-down power of a screw is considerably stronger than a nail, especially power nailing. Some power nailers will blow the head halfway through the board, eliminating 50% of its hold-down power.
- Predrill holes on all ends of the pieces. A nail or screw applied close to the end of the piece will fracture the wood and reduce the hold-down power considerably.
- Apply at least a clear water repellant to all surfaces as soon as possible after construction. Just as the water repellent repels water from soaking into the wood from rain and other weather, the sealer dramatically slows down the evaporation rate of the wet wood installed when using treated lumber that is not dried after treatment. A semi-transparent stain/water repellant will protect better than clear because the pigment blocks more of the damaging UV rays.