Filters
Shopping Options
Marine Plywood
Marine Plywood Sheets
Marine plywood, also known as marine ply, is a high-quality plywood sheet designed for projects where moisture resistance and board quality matter. It is commonly used for joinery, wall lining, furniture, roofing work, exterior projects, boat repairs and other marine-related applications. While marine plywood offers better moisture resistance than standard plywood, exposed faces and cut edges should still be sealed before outdoor or high-moisture use.
Choosing Between 12mm and 18mm Marine Plywood
Our marine plywood sheets are available in full 2440mm x 1220mm sizes, with practical 12mm and 18mm options depending on the strength, weight and handling requirements of your project.
- 12mm marine plywood - a lighter option for wall lining, cabinets, furniture, panels, covered roofing details and general joinery.
- 18mm marine plywood - a thicker, more rigid sheet for flooring, roof decking, construction work and heavier-duty applications.
Where Marine Plywood Is Used
Marine grade plywood is suitable for a wide range of building, renovation and joinery jobs where a standard board may not offer enough moisture resistance. Common uses include wall lining, furniture, cabinets, flooring, roof decking, exterior joinery, boat repairs and other moisture-prone areas.
Is Marine Plywood Waterproof?
Marine plywood is often searched for as waterproof plywood, but it should not be treated as a finished waterproof surface. It is designed to handle moisture better than standard plywood, but for external or damp-area use, the board should be sealed or coated, especially around cut edges, joints and exposed faces.
How to Seal and Maintain Marine Plywood
For long-term performance, use a suitable wood treatment, coating or sealant before installing marine plywood in outdoor or high-moisture areas. Pay particular attention to cut edges and fixing points, as these areas are more exposed to moisture ingress.
Why Buy Marine Plywood from MGN?
MGN Builders Merchants supplies marine plywood sheets for trade and DIY projects, with 12mm and 18mm options available for different site, joinery and exterior applications. Choose the sheet thickness that best matches the strength, handling and installation requirements of your project.
FAQs
What should I check before buying marine plywood?
Check the sheet thickness, size, board standard and intended use before buying. For trade or site work, also consider moisture exposure, handling weight, support requirements and whether the board needs sealing before installation.
Is marine ply the same as marine grade plywood?
Yes, marine ply and marine grade plywood are commonly used to describe the same type of moisture-resistant plywood. Always check the product specification, especially if the job requires a recognised standard such as BS1088.
Does marine plywood need sealing before use?
Yes, the board should be sealed before outdoor or high-moisture use. Cut edges, joints and fixing points are the most exposed areas, so they need proper protection to help reduce moisture ingress.
Should I choose marine ply or external plywood?
Choose marine ply when moisture resistance, board quality and durability are more important. External plywood can be a more cost-effective option for general outdoor work where exposure is lower and the sheet is correctly treated.
Which thickness should I choose?
Choose a 12mm sheet for lighter work such as wall lining, cabinets, furniture, panels and general joinery. Choose an 18mm board when you need extra rigidity for flooring, roof decking or heavier-duty site applications.
How should marine plywood sheets be stored on site?
Store the sheets flat, dry and raised off the ground before installation. Keep them covered and well ventilated, and avoid leaving them exposed to standing water or direct weather before they are sealed and fitted.