Trex Joist Spacing
Trex pioneered the wood alternative decking industry nearly 20 years ago and we continue to innovate best in class products for high performance low maintenance outdoor living.
Trex joist spacing. Trex transcend and select horizontal railings are made to be installed at maximum of 6 1 83 m or 8 2 44 m on center depending upon type of railing you choose. Deck joist spacing should never exceed 16 on center with the exception of max deck boards which allow for maximum 24 on center. Trex signature railing and rod rail are made to be installed at maximum 6 or 8 clear span between posts.
Those railings are not true 6 72 or 8 96 in length. When designing a new trex or composite deck the spacing between floor joists should be 12 inches on center. Before building a composite deck always read the installation instructions from the manufacturer paying special attention to the required joist spacing for composite decking.
Trex was the first to invent the wood alternative decking category. When stacking decking bundles supports dunnage should start approximately 8 in 203 mm from each end and be spaced approximately 2 ft 0 61m on center. So when would you ever need to use 12 inches oc.
Plus building with trex is as easy as wood yet leaves no painting staining splintering or rotting to worry about ever. On center means that the measurement should be taken from the center of a joist edge to the center of the next joist edge. If adding additional framing be sure to keep all boards level and in plane across the tops.
Store decking on a flat level surface and always use proper supports dunnage. Some brands like weardeck let you get away with more reinforced with a layer of fiberglass on both the top and bottom weardeck boards easily allow for spans of 24 inches oc. Most composite decking materials like trex composite decking require minimum joist spacing for composite decking at 16 on center spacing for straight decking and 12 on center joist spacing for 45 degree angle diagonal decking.
You also may have to install more stair stringers. Trex from the inside out. For a more rigid feel 12 or less may be preferred.