1 - Composite Deck Building - Substructure - YouTube Mar 25, 2011 ... You must conform to local building codes but a 12" joist spacing is necessary to support the composite decking.
Composite lumbers add other materials such as wood flour, sawdust, or ground-up peanut shells. They can be solid throughout, or they may have a hollow, ribbed center to reduce weight.
The span of a beam is dependent on a few variables. The species of lumber, size of lumber and the load it carries. Fewer posts on upper level decks are typically more desirable to the occupants and this drives the use of larger framing materials for longer spans.
If you invest in a composite deck you should probably use joist tape to ensure the life of the deck frame. If you double your beams you should run 3” tape along the top surface to ensure water doesn’t get between the two 2x10’s.
The solid board can be 'bent' on edge to a radius of 5m, which makes it great for use as garden edging. Please note that the solid decking boards can be used for screening with a maximum span between uprights of 1500mm on a continuous span (on edge).