Marine plywood, made to IS:710
Marine grade is the most water-resistant plywood we make. It uses undiluted phenolic resin and a dense, gap-free core, and it is certified to IS:710. It is specified where water is a permanent condition rather than an occasional event — not because it is the best board in every situation, but because it is the right one when nothing else will hold.
What Marine grade actually means
Marine plywood is defined by its bond. The phenolic resin is used undiluted, and the core is built to be denser and free of gaps, because a void inside a board that lives in water is a channel for it. IS:710 is the Indian Standard that governs marine-grade plywood, and it is a materially higher bar than the IS:303 grades.
Boards in this grade are tested by boiling them continuously for 72 hours and confirming they have not delaminated. That measures the bond — it says nothing about whether the core beneath it was built without voids, which is a separate question worth asking of any manufacturer.
Where to use it
- Boat building and marine fittings
- Permanently submerged or semi-submerged installations
- Industrial tanks, enclosures and process areas
- Dock, jetty and waterside structures
- Any application where water is a constant, not an event
Where it is the wrong choice
- A domestic kitchen
- BWP already survives a 72-hour continuous boil. Marine grade indoors is usually money spent on a margin you will never reach.
- Bedrooms and living rooms
- These see ambient humidity only. MR grade is engineered for exactly that.
- A fire-code requirement
- Water resistance and fire resistance are unrelated. Where a code requires FR grade, no amount of Marine substitutes.
Specification
| Grade | Marine Plywood (Marine) |
|---|---|
| Indian Standard | IS:710 |
| Bond | Undiluted phenolic resin |
| Thicknesses | 4 mm · 6 mm · 9 mm · 12 mm · 16 mm · 19 mm · 25 mm |
| Sheet sizes | 8 × 4 ft (2440 × 1220 mm) · 7 × 4 ft (2135 × 1220 mm) · 6 × 4 ft (1830 × 1220 mm) |
| Custom sizing | Panels cut to your cutting list for bulk orders |
Marine applications are usually structural, so the thicker end of the range is the norm. Thickness follows span and load, not grade.
How this board is made
The resin changes with the grade. Nothing else does — every board runs the same seventeen consecutive stations at our line in Hassan, Karnataka, and these four apply to Marine grade exactly as they do to every other:
- Composed core
- Core veneers jointed edge-to-edge into full-size sheets before assembly, so the finished board has no internal voids.
- Calibrated thickness
- Both faces ground after pressing so the whole sheet is one uniform thickness — a different operation from sanding.
- ACC preservative treatment
- Dipped in an acid copper chromate bath as a station on the line, so the treatment penetrates rather than coating the surface.
- Laboratory tested
- Samples from every batch tested against IS:303 and IS:710 — moisture content, glue shear strength and water resistance — before dispatch.
Architects and bulk buyers are welcome to walk the line and take a board away to cut open before ordering.
Choosing between the grades
Grade is a water rating, not a quality ranking. The most common and most expensive error is buying up when the room does not need it.
Guides worth reading first
Questions we get asked
What is marine plywood?
Plywood bonded with undiluted phenolic resin and built with a dense, gap-free core, certified to IS:710. It is intended for constant water exposure.
Is marine plywood the same as BWP?
No. Both are phenolic-bonded and both undergo a 72-hour boil test, but Marine grade uses undiluted resin with a denser core and is certified to IS:710.
Do I need marine plywood for my kitchen?
Generally not. BWP already withstands a 72-hour continuous boil, which is beyond anything a domestic kitchen delivers.
Does marine plywood still need its edges sealed?
Yes. The bond keeps the layers together; it does not stop exposed core veneer at a cut edge from absorbing water.
Tell us the room, the thickness and the quantity and we will quote against it — including when a cheaper grade is the right answer.