Types of Plywood
Different varieties of plywood exist for different applications:
Softwood panel is usually made either of cedar, Douglas fir or spruce, pine, and fir (collectively known as spruce-pine-fir or SPF) or redwood and is typically used for construction and industrial purposes.
The most common dimension we carry is 4 feet × 8 feet. Plies vary in thickness from 1.4 mm to 4.3 mm. The number of plies depends on the thickness and grade of the sheet but at least three are required as the minimum odd number of plies. Roofing can use the thinner 5/8" (15 mm) plywood. Subfloors are at least 3/4" (18 mm) thick, the thickness depending on the distance between floor joists. Plywood for flooring applications is often tongue and groove; This prevents one board from moving up or down relative to its neighbor, so providing a solid feeling floor when the joints do not lie over joists. T&G plywood is usually found in the 1/2" to 1" (12–25 mm) range.
Hardwood plywood is made out of wood from angiosperm trees and used for demanding end uses. Hardwood plywood is characterized by its excellent strength, stiffness and resistance to creep. It has a high planar shear strength and impact resistance, which make it especially suitable for heavy-duty floor and wall structures. Oriented plywood construction has a high wheel-carrying capacity. Hardwood plywood has excellent surface hardness, and damage- and wear-resistance.
Tropical plywood is made of mixed species of tropical wood. Originally from the Asian region, it is now also manufactured in African and South American countries. Tropical plywood is superior to softwood plywood due to its density, strength, evenness of layers, and high quality. It is usually sold at a premium in many markets if manufactured with high standards. Tropical plywood is widely used in the UK, Japan, United States, Taiwan, Korea, Dubai, and other countries worldwide. It is the preferred choice for construction purposes in many regions due to its low cost. However, many countries’ forests have been over-harvested, including the Philippines, Malaysia and Indonesia, largely due to the demand for plywood production and export.
High-strength plywood also known as aircraft plywood, is made from mahogany and/or birch, and uses adhesives with increased resistance to heat and humidity. It was used for several World War II fighter aircraft. Although the British-built Mosquito bomber, nicknamed "The Wooden Wonder", was constructed of a plywood monocoque, this was formed in moulds from individual veneers of birch, balsa and birch, rather than machined from pre-laminated plywood sheets.
Structural aircraft-grade plywood is more commonly manufactured from African mahogany or American birch veneers that are bonded together in a hot press over hardwood cores of basswood or poplar or from European Birch veneers throughout. Basswood is another type of aviation-grade plywood that is lighter and more flexible than mahogany and birch plywood but has slightly less structural strength. Aviation-grade plywood is manufactured to a number of specifications including those outlined since 1931 in the Germanischer Lloyd Rules for Surveying and Testing of Plywood for Aircraft and MIL-P-607, the latter of which calls for shear testing after immersion in boiling water for three hours to verify the adhesive qualities between the plies and meets specifications.
Decorative plywood (overlaid plywood)
Usually faced with hardwood, including ash, oak, red oak, birch, maple, mahogany, Philippine mahogany (often called lauan, luan or meranti and having no relation to true mahogany), rosewood, teak and a large number of other hardwoods.
Flexible plywood is designed for making curved parts, a practice which dates back to the 1850s in furniture making.
Aircraft grade plywood, often Baltic birch, is made from 3 plies of birch, as thin as 1/16" thick in total, and is extremely strong and light. At 3/8" thick, mahogany 3-ply "wiggle Board" or "Bendy Board" come in 4' x 8' sheets with a very thin cross grain central ply and two thicker exterior plies, either long grain on the sheet, or cross grain. Wiggle board is often glued together in two layers once it is formed into the desired curve, so that the final shape will be stiff and resist movement. Often, decorative wood veneers are added as a surface layer.
In the UK single ply sheets of veneer were used to make stovepipe hats in Victorian times, so flexible modern plywood is sometimes known there as "Hatters Ply", although the original material was not strictly plywood, but a single sheet of veneer.
Marine plywood is manufactured from durable face and core veneers, with few defects so it performs longer in both humid and wet conditions and resists delaminating and fungal attack. Its construction is such that it can be used in environments where it is exposed to moisture for long periods. More recently, tropical producers have become dominant in the marine plywood market. Okoumé from Gabon is now the accepted[by whom?] standard for marine plywood, even though the wood is not very resistant to rot and decay. Each wood veneer will be from tropical hardwoods, have negligible core gap, limiting the chance of trapping water in the plywood and hence providing a solid and stable glue bond. It uses an exterior Water and Boil Proof (WBP) glue similar to most exterior plywoods.
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 Okoumé or Meranti.
Marine plywood is frequently used in the construction of docks and boats. It is much more expensive than standard plywood: the cost for a typical 4-foot by 8-foot 1/2-inch thick board is roughly $125 U.S. or around $3.50 per square foot, which is two to three times as expensive as standard plywood, depending on grade.
Other types of plywoods include fire-retardant, moisture-resistant, wire mesh, sign-grade, and pressure-treated. However, the plywood may be treated with various chemicals to improve the plywood's fireproofing. Each of these products is designed to fill a need in industry.
Call today and ask about our current Specials!!! ~~~Free Delivery Available
Here at Chesapeake Plywood we try to accommodate any request. We are a wholesale distribution company and have a minimum order for pickup and delivery. If these minimums are not met, a service charge can be added to accommodate. We have a $250.00 minimum for will calls and a $ 500.00 minimum for free delivery in MD, Northern VA, South Eastern PA east to Philadelphia. We also make weekly deliveries to Southern VA/NC/SC/NJ/NYC/DE Louisville, KY and the Indiana area. We, however, can make arrangements to deliver almost anywhere. We will be glad to refer any of our customers to one of our retail suppliers. For free deliveries please give us a call at 410 244-0055 to find out what the minimum order would be, to deliver in your area.