What thickness of plywood is best for a trailer floor?
It depends on the trailer type and cross-member spacing. Enclosed cargo on 16-inch centres: 1/2 inch HDO works; on 24-inch centres step up to 3/4 inch. Flatbed deck-over: 1-1/8 inch to 1-1/2 inch dense hardwood plywood (Apitong). Gooseneck cargo and RV subfloor: 3/4 inch. Horse trailer stall: 3/4 inch minimum with anti-slip overlay. The thickness is set by cross-member spacing and load, not by the type of plywood.
Is marine plywood good for trailer floors?
Yes, for specific use cases. Marine plywood (BS 1088 or APA marine per PS 1) carries an exterior phenolic glue and low core voids, which makes it appropriate where the floor sees standing water or constant condensation (boat trailer, fish-hauling, dock-staged storage). For dry cargo applications, HDO is the more cost-effective choice because the phenolic film overlay is built specifically for abrasion resistance from pallet jacks and forklift wheels.
Do I need anti-slip plywood for a trailer?
Only if the floor sees foot, hoof, or tire traffic on a frequently wet surface. Livestock decks (horse, cattle, sheep), motorcycle and ATV ramps, and open utility trailers used for landscaping all benefit from a hex or mesh phenolic film. For enclosed cargo where pallet jacks roll, smooth HDO is better than anti-slip because the wheels skid on the hex pattern.
How long does a trailer plywood floor last?
With sealed edges, dry storage and routine inspection: up to 15 years for Apitong, up to 12 years for HDO Premium 2S, up to 10 years for HDO Basic 1SF or anti-slip film-faced. With rough use, no edge sealing, or constant winter exposure to road salt, expect roughly half those numbers. Edge sealing on every cut is the single biggest factor in service life regardless of grade.
Can I overlay an existing trailer floor instead of replacing it?
Only if the existing substrate is structurally sound. If the underlying floor has soft spots, delamination at the cut edges, or fastener pull-through around screw heads, an overlay just hides the problem. Where the substrate is solid but the face is worn (scuffed phenolic, abraded film, surface scratches), a 3/8-inch overlay sheet screwed and edge-sealed over the original is a quick and durable fix. A floor that fails the screw-pull test is past overlay territory and needs full replacement.
