An outdoor deck will need to perform through hot and cold and wet and dry conditions. All materials for deck building must be able to resist rot, decay and insect damage. Some wood materials such as redwood and cedar are naturally resistant. Other wood materials such as pine need to be impregnated with chemicals to be used outdoors.
Wood materials need to be stained with an oil based stain to prevent the wood from drying out too quickly and checking or cracking. Wood will naturally gray over time if not stained. Use stainless or triple galvanized fasteners and hardware. Standard interior nails, screws, and hardware will corrode.
It is very important to properly flash your ledger board connection to keep water from penetrating the house wall. Water damage can be very expensive to repair. Also your frost footings must be installed below the frost line to prevent them from lifting during freeze and thaw cycles.
Composite materials will expand and contract with variations in temperature because they are composed of plastic. Make sure you properly space the deck boards depending on the temperature when you install the decking and follow the manufacturer's instructions to prevent buckling.
Cleaning a deck is a must. Over time dirt, mildew, leaves, and debris will cover your deck. You can use a power washer and specially products to clean and restore your decks surfaces.