Trex joist spacing

[mattradk]

Most deck designs I've seen specify 16" max for deck spacing with Trex as the deck board material. The Trex installation handbook recommends 16" as a max joist spacing as well. Do you folks usually use 16"? I've heard some other designers say 12" should be the max, but 12" is tough to justify other than "I think 12" is better." Thanks

 

[XR250]

16" works fine based on my personal experience

 

[mattradk]

Thanks. I was never a fan of composite decking. Almost every place I'd seen it used in the past (15-30 years), it sagged after a period of time. But maybe these products have improved. I would hope so.

 

[phamENG]

Most issues I've seen have involved installation in non-deck applications - hand rails, for instance. The UV degradation causes them to droop like crazy. 3-span at 16" o/c, though, I've never seen an issue.

 

[dauwerda]

I could be remembering wrong, but I believe a tighter joist spacing is recommended if the decking is installed diagonally as well.