Deck Joists

Deck joists are attached to the deck's beams and serve the purpose of supporting the deck's flooring system. The size and spacing of the joists will depend on a deck's structural requirements as determined by the size, shape among other factors. As joists are an important framing component they also need require pressure treated wood.

A double joist is also sometimes required for certain deck structures. A double joist essentially uses two pieces of wood for extra support. Where two floor boards meet up, they need to be secured to a double joist for extra support.

Rim joists or header joists which are the outer joists need top grade pressure treated wood. Rim joists also play a key role in holding up the deck's flooring as well as concealing the ends of the other joists.

Joists often sit on the beams and are attached using specific metal fasteners. Many let the joists extend past the beams during construction but later need to be cut to their appropriate length.

Joist hangers are often used to attach the joists to a ledger if one is attaching the deck their home. Joist hangers are made of metal and offer strength for mounting.

Just like the beams, joists are most commonly installed with the crown side up.