Marine plywood

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In construction, marine plywood is a specially treated plywood that is designed to resist rotting in a high-moisture environment. Marine plywood is frequently used in the construction of docks and boats.

1 Advantages of marine plywood
2 Disadvantages of marine plywood
3 Standards and ratings
4 Alternatives to marine plywood
5 References

[edit] Advantages of marine plywood

Durability - small scratches through painted plywood may expose the interior to water. Inexpensive plywood may not last long when it is damp
Strength - marine plywood is stronger and has consistent mechanical properties: no voids.
Workability - marine plywood is usually easier than fiberglass to cut and bend
Resistance to Warping - marine plywood (with the exception of Fir-based plywoods) will resist warping or check

[edit] Disadvantages of marine plywood

Cost - Marine plywood is much more expensive than standard plywood. Costs for a typical 4 foot by 8 foot 1/2 inch thick board is roughly $75 to $100 US or around $2.5 per square foot. This is about three times as expensive as standard plywood.

Marine plywood comes in several common thicknesses:

1/8 inch (4 mm)
1/4 inch (6 mm)
3/8 inch (9 mm)
1/2 inch (12 mm)
3/4 inch (18 mm)

[edit] Standards and ratings

Marine plywood can be graded as being compliant with BS 1088, which is a British Standard for marine plywood.

There are few international standards for grading marine plywood and most of the standards are voluntary. Some marine plywood has a Lloyd's of London stamp that certifies it to be BS 1088 compliant. Some plywood is also labeled based on the wood used to manufacture it. Examples of this are Okoume or Meranti

[edit] Alternatives to marine plywood

There are several alternatives to marine plywood. Some of these are engineered materials. Examples include fiberglass-type composites using glass, Kevlar, or graphite fiber, and bonded materials using lightweight cores such as expanded polystyrene or honeycomb.