How far apart should deck support beams be?
16″
Most decks use 16″ on center spacing for joists. Most decking is not strong enough to support wider spans than 16″. Some builders reduce joist spacing to 12″ on center to strengthen the deck frame or to increase maximum allowable joist spans.
How far do you have to sister a joist?
Sistered joists do not have to run the length of the original joist. While no specific rule exists for how long a sistered joist should be, a commonly held rule is that a sistered joist ⅔ the length of the original is adequate – only if you cannot run the joist the entire length.
How Much Should sister joists overlap?
Joist lap at a load-bearing wall would be three inches overlap minimum and three nails minimum per IRC 502.6. 1.
How far can a beam span without support?
A 2×10 beam – made up of two 2x10s nailed together – can span up to 11′ without support beneath a deck that is 4′ wide. For a more normal-sized deck, the same beam can span 8′, supporting a deck that is 8′ wide. You can also triple a 2×10 beam.
How far can a 2×6 beam span without support?
2-grade 2×6 joists can span up to 10 feet 9 inches from beam to beam when spaced the standard 16 inches apart with a maximum live load of 30 inches per square foot. In comparison, No. -1 grade lumber can span slightly further to 10 feet 11 inches under the same parameters.
Can you sister deck joists?
To repair or strengthen a deck joist, sistering a board of equal width and thickness for part or all of its length is common practice. It is also used to extend the existing deck area by cantilevering sistered joists over the end beam or to connect new deck construction with old.
Does Sistering a joist make it stronger?
Joist sistering is adding an extra identical floor joist, to a damaged or inadueqate floor joist, and tieing the two together with screws or nails. It is a very effective way of adding the additional strength needed to hold up a sagging floor.