We at Phuket Marine Plywood are here for all of your marine plywood needs.  No order is too big or too small.  Conveniently located near Chalong Pier in Phuket, Thailand, we will make sure that you get the right wood for the right price.

About Marine Plywood (BS 1088)

Marine plywood is specially treated to resist rotting in a high-moisture environment. Marine plywood is frequently used in the construction of docks and boats. It 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, which is about three times as expensive as standard plywood.

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.

One Boat Designer says:

We regret that some suppliers of epoxy products are misinforming amateur boat builders, giving the impression that epoxy products are a remedy for all ills. Sometimes the statements sound like the old "medicine men" of the past. For example, we've seen one supplier state, "lf exterior plywood is given the required two coats on all surfaces, it renders that plywood acceptable for all boatbuilding and exterior projects. . . . visible minor voids. . . . . can easily be filled".

We've had many prospective builders of our designs question our naval architects citing this or similar statements. In almost all cases, these builders got the impression that by slopping some of this supplier's products onto inferior grade (but readily available) plywood panels (such as "C", "D", "interior", or even "shop" grades) the panel would somehow be brought up to a marine grade quality. Nothing could be farther from the truth, and such statements are dangerous to say the least. Here's why. First, while there is probably no difference in the waterproof glues used between the typical "exterior" grade and the higher-priced "marine" grade panel, there definitely is a difference in the quality and perhaps the type of wood used in the inner cores. The marine grade panel is made with inner cores free of voids (often of solid core construction), and of the same lumber as the faces. The face veneers of the marine panel are usually of "A" or sometimes a "B" grade so that there are no exposed knot holes or other defects which could weaken the panel. This high-quality void-free panel offers predictable engineering qualities, fracture-free installation when bending in place over properly designed contours, and will not fail under stress due to voids.

Conversely, the exterior grade panel, while often used in place of the marine grade panel due to cost, may contain voids in the inner cores not visible to the eye. Such voids can be large and end up in areas of the hull subjected to high stress when used for planking. Furthermore, the wood types used for the inner cores can differ from the outer veneers, perhaps being of
an inferior wood from a strength and durability standpoint. Exterior grade panels with face veneers of "C" or lesser grades, such as "D" or shop grade, may be full of knots, unpatched knot holes, checks, splits, and other defects, not to mention even greater inferiority in the inner cores.

While it is possible that all visible voids, such as those on the outer surfaces, could be filled with epoxy, this would not strengthen the panel other than to stiffen it a bit. But what about the voids in the inner plies which are equally important to panel strength when subjected to stress? Since they are probably not even visible, how can they be filled with epoxy? And even if they could be filled all epoxies are weak in tensile strength (although high in compressive strength; and thus could never approach the strength provided by the wood fibers that are missing due to invisible voids.

What does BS 1088 mean?

BS 1088
From Wikipedia, the free encyclopedia

In materials, the BS 1088 specification is a marine plywood specification that applies to plywood produced with untreated tropical hardwood veneers that have a set level of resistance to fungal attack. The plies are bonded with WBP glue. Although the initials BS are for "British Standard", the finished product does not have to be "British made". The standard is associated with Lloyd's of London since it performs testing of products to this standard.

WBP Glue Line -- BS 1088 plywood must use an adhesive, which has been proven to be highly resistant to weather, micro-organisms, cold and boiling water, steam and dry heat. The product's bonding must pass a series of British Standard tests.

Face Veneers -- These must present a solid surface that is free from open defects. Face veneers must be free of knots other than "sound pin" knots, of which there shall be no more than six(6) in any area of one(1) square foot, and there can be no more than an average of two(2) such knots per square foot area over the entire surface of the plywood sheet. The veneers must be reasonably free from irregular grain. The use of edge joints is limited, and end joints are not allowed.

Core Veneers -- Core veneers have the same basic requirements as face veneers, except that small splits are allowed, and there is no limit on the number of pin knots or edge joints. However, end joints are not permitted.

Limits of Manufacturing Defects -- Defective bonds, pleats and overlaps, and gaps in faces are not permitted. Occasional gaps may be repaired using veneer inserts bonded with the proper adhesive.

Moisture Content -- BS 1088 plywood must have a moisture content between 6% and 14% when it leaves the factory.

Finishing -- Boards will be sanded on both sides equally.

Length & Width -- The length or width of a board produced as a standard size shall not be less than the specified size nor more than 6.3 mm (0.25") greater than the specified size.

Squareness -- The lengths of the diagonals of a board shall not differ by more than 0.25% of the length of the diagonal.

Thickness Tolerances -- Tolerances vary as follows.

• 4 mm +.02/-0.6 6 mm +.04/-0.65 9 mm +.06/-0.75 12 mm +.09/-0.82
• 15 mm +.1/-0.9 18 mm +.12/-0.98 22 mm +.16/-1.08 25 mm +1.8/-1.16

From the above we can assume that 6 mm material will arrive at thickness' between 6.04 mm and 5.35 mm.

Face Veneer thickness -- For any three-ply construction, which applies to 3 and 4 mm material, each face veneer shall be not thinner than 1/8 of the total thickness of veneers assembled dry. Since the dry thicknesses of the boards are 3.6 and 4.6 respectively, we can assume that for these thicknesses only the face veneers will be as follows:

• 3.6 mm dry x 12.5% (1/8) = 0.45 mm 4.6 mm dry x 12.5% (1/8) = 0.575 mm

Multi-Ply Construction-- This applies to boards thicker than 4.8 mm (3/16")

• Each face veneer shall be a minimum of 1.3 mm and not thicker than 3.8 mm.
• Each core veneer shall be no thicker than 4.8 mm