Composite Deck Joist Requirements
| Brand | Perpendicular | Diagonal | Notes |
|---|---|---|---|
| Trex* | ≤16″ o.c. | ≤12″ o.c. | Verify your specific product sheet. |
| TimberTech* | ≤16″ o.c. | ≤12″ o.c. | Some lines allow 24″ straight. |
| AZEK* | ≤16″ o.c. | ≤12″ o.c. | Hot climates benefit from tighter spacing. |
*Unaffiliated; check manufacturer docs for current specs.
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