What Is Marine Grade Plywood?

Marine-grade plywood is made from core veneer sheets of Western Larch or Douglas-fir wood. The cross-Laminated process is used to make marine-grade plywood. This grade plywood is more durable and expensive compare to common plywood. 

To make boats, ports, and exterior uses marine plywood is the best material. We can use marine-grade plywood for such applications where moisture and dust are present. Marine plywood wood performs well in bad weather also.

Plywood has many different grades and all have their own strengths. There are many types of plywood available in the market. Marine plywood comes in many different grades, sizes, and weights. 

If you want plywood for boats and fences and other exterior projects, then marine plywood is a better choice for you. Marine plywood does not deteriorate for many decades even after exposure to moisture.

Dutch door manufacturer Cornelius Bruinzel was first introduced to marine plywood in the 1930s. According to Wikipedia, During world war 2, Boats are built with Marine Plywood. Boats made of marine plywood are much lighter and stronger than wooden boats. Due to its lightness, it was very easy for the army to move the boat from one place to another.

Is marine grade plywood waterproof?

Is marine grade plywood waterproof?
Is marine-grade plywood waterproof?

No, marine plywood is not 100% waterproof. Many people believe that marine plywood is completely water-proof but it is not true. Whenever it is about wood, nothing can be 100% waterproof. But it is more durable in water and moisture than other wooden materials.

Marine-grade is good quality, hardwood plywood made with waterproof glue. It is the most preferred construction material among buildings and furniture materials, Due to its excellent properties. Marine plywood is not treated with chemical treatment. So plywood is not anti-termite and rot-resistant and this is not harmful.

Marine Plywood Types

Marine-grade plywood is available in the following types of grades. To make good quality plywood, the veneer sheet (thin layers) should be of good quality. A large gap is present in low-quality veneer, a large gap is a risk of moisture getting inside. So the durability of plywood is reduced.

  1. A-A Marine-Grade Plywood: The veneers (piles) used in this grade of plywood do not have knots. This grade plywood available in 4 feet by 8 feet or 5 feet by 12 feet and ½-inch thickness.
  1. B-B Marine-Grade Plywood: Grade B-B allowing for some surface knots. This grade plywood available in 4 feet by 8 feet and  ¾-inches thick.
  1. A-B Marine-Grade Plywood: In veneers (piles) used in this grade Somewhere knots are present. 
  1. Medium-density overlay (MDO): MDO grade made with high-quality veneer, thermosetting, and resin. A layer of resin is applied to the plywood surface with under presser. To make strong and durable Pressure treatment and heat treatment process applied. Because of which it becomes very smooth. so it is perfect for painting. This grade is much stronger. It is available in the market in the size of 4 feet by 8 feet. Their thicknesses are available in ⅜-inches, ⅝-inches, ½-inch, ¾-inches, and 1 inch.
  1. High-density overlay (HDO):  Plywood of this grade is more smooth than MDO grade because more resin is used to make it. This grade comes in 4 feet by 8 feet size and either ½-inch or ¾-inch thickness.

Uses of marine plywood?

1. Boats and Boat Parts

Boats and Boat Parts

If you like fishing then maybe you also like a boat. And if you are looking to buy a boat, then you can save good money and buy a boat made by Marine Plywood. Which is quite waterproof and less expensive compare to wood.

Marine Plywood is a perfect material for making a boat. To keep it durable in water for a long time, sealing the outside and inside of your boat. After sealing The marine plywood will be completely waterproof for a long time.

Marine plywood use used to making boat parts. Which are durable for many decades.

2. Lake Platform

Lake Platform
Lake Platform

The lake platform is a good place to spend time with family, relax, and for yoga. The lake platform is always in contact with water. Marine Plywood lake is the best material on the Lake platform project.

3. Boat Docks

Boat Docks are a structure made in water for handling boats or ships. In olden times boat docks were made from wood lumbar. Which required repairing every year. Whereas docks made from marine plywood do not require much care and are less expensive.

4. Deck

Using timber to build a deck can be expensive and regular maintenance is required. Whereas if we use Marine Plywood then the deck can be installed with less money and it lasts long.

5. Bathroom door and kitchen platform

The bathroom and the kitchen both are places where water and moisture are present. In such a situation, the door of the bathroom should be such that it can withstand the daily moisture and Marine Plywood is a very good choice for the kitchen platform and bathroom door.

Marine plywood is not chemically treated. So that it is not harmful, so we can use it in the kitchen without any risk. Mainly used to make a kitchen platform.

6. Caravan Making

Caravan Making
Caravan Making

Wood has long been used to make caravans. To make the base and roof of the caravan. Marine plywood is the best material for roofing. It is stronger and less expensive material than wood and steel sheet.

How to identify marine plywood?

How to identify marine plywood?
How to identify marine plywood?

It is very difficult for a common person (who does not know about plywood), To identify marine-grade plywood, only one expert carpenter can recognize it well. 

But there are some tips for the common person that will help in identifying that too.

  1. Both sides should have a smooth finish.
  2. Check the label when purchasing plywood. Do not buy plywood without labels.
  3. If plywood is bent more than 18mm, That means is not well made.
  4. Estimate the weight by lifting the plywood from one part. Heavyweight plywood is always carrying more density.
  5. Always buy from a trusted shop.
  6. Good plywood does not have many knots on its surface. Due to excess knots, moisture can reach inside and the plywood deteriorates quickly.

Marine-Grade Plywood vs Pressure Treated.

Marine-Grade Plywood vs Pressure Treated.
Marine-Grade Plywood vs Pressure Treated.
Marine-grade PlywoodPressure Treated
Marine-grade plywood is not normal plywood. It is designed to be used in a humid place.Pressure-treated plywood is common plywood. Which is made from the process of chemical and pressure treatment to prevent the wood from decaying, or rotting.
Marine grade is not harmful in any way. Because chemical treatment is not used to make it.Pressure Treated can be harmful to use. Can not use it in the kitchen.
Marine-grade Plywood can be used for marine applications.Pressure Treated Plywood is not suitable for marine applications to use.
This grade plywood can be used for exterior and interior applications. It performs well in both environments.It can be used for interior applications only.
Water-resistant glue is used to make it.Good quality glue is used in production but not waterproof glue.
It can withstand every season for a long time. It lasts for decades.Plywood may need to be changed every few years.
Marine-Grade Plywood vs Pressure Treated

There are many advantages and disadvantages of Maine plywood.

Marine Plywood Alternative

Fiberboard: Fiberboard is the first best alternative to marine plywood. Fiberboard is a medium density that is quite strong and long-lasting. This material is a type of engineered wood product that is made out of wood fibers.

It is available in the market at a lower price than Marine Plywood. Fiberwood is made from fresh or recycled wood material. Small pieces of softwood are mixed with the wax resin.

Ribbon Grain Plywood: Ribbon grain plywood is made by gluing several thin sheets of wood. The surface of this plywood is smooth which prevents moisture well. It is a very strong wood sheet material but not as much as marine plywood.

Fiber Cement Board: Fiber Cement Board material is a mixer of wood fiber (small pieces of wood) and cement. After hot pressing and drying treatment, it forms a very strong material.

The fiber cement board is a well-known material that is in demand in almost every kind of construction application. For exterior walls and ceilings also use fiber cement board.

Reinforced Polyurethane Foam: Reinforced Polyurethane Foam is a rot-resistant alternative to good plywood. In the market, it is easily available in five densities ranging from $20 to $35 per cubic foot.

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