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Sanded Plywood

Sanded plywood is used in a wide variety of applications. Interior uses include cabinetry, furniture manufacturing, paneling and shelving. Exterior uses include specialty construction and industrial applications such as fences, soffits, truck and boxcar linings, commercial refrigerators and other applications where exposure to high-moisture is anticipated and smoothness and/or appearance are important.

Sanded plywood certified by TECO is manufactured in conformance with the requirements of the U.S. Department of Commerce Voluntary Product Standard PS 1, Structural Plywood. PS 1 establishes minimum requirements for the principle types and grades of construction and industrial plywood including wood species, veneer grading, glue bond, panel construction and workmanship, dimensions and tolerances, marking, moisture content, quality control and certification.

Sanded plywood manufactured for use in exterior applications must meet the requirements for an “Exterior” bond classification and be manufactured with minimum “C” grade veneers. Sanded plywood typically used in interior applications meets the requirements for “Exposure 1” bond classification and can include “D” grade veneer as back and/or inner plies. Bond classification is related to the moisture resistance of the glue bond under intended end-use conditions and does not relate to the physical (erosion, ultraviolet, etc) or biological (mold, fungal decay, insect, etc) resistance of the panel. Sanded plywood with and Exterior bond classification is suitable for repeated wetting and redrying or long-term exposure to weather or other conditions of similar severity. Sanded plywood with an Exposure 1 bond classification is suitable for uses not permanently exposed to the weather and is intended to resist the effects of moisture on structural performance as may occur due to construction delays or other conditions of similar severity.

Sanded plywood manufactured in conformance to PS 1 is identified with a species Group No. that is used to classify species covered by PS 1. Group numbers include 1, 2, 3, 4 and 5. Strength and stiffness properties of species in Group 1 are typically highest, while the strength and stiffness properties of species in Group 5 are the lowest. The Group number on a panel generally identifies the largest numbered species group (i.e. Group 4 is larger than Group 1) of the face or back veneers, but may also be based on performance testing.

Sanded plywood is available in several grades, which are based on the grade of the veneers and the panel construction. Veneer is classified into six (6) distinct grades including N, A, B, C, C Plugged and D. The grades differ from each other by the number, type and size of growth and open characteristics and repairs allowed. For example, Grade N veneer, the highest quality veneer available, is intended for a natural finish and must be free from knots (i.e. growth characteristics), knotholes, pitch pockets, open splits and other open characteristics and stain. Grade D veneer is the lowest quality veneer classified in PS 1 and permits knots and knotholes up to 3 inches measured across the grain, as well as any number of plugs, patches, worm or borer holes and sanding characteristics. Panels are also available with resin-impregnated fiber overlays that provide a smooth surface that may offer high resistance to chemicals and abrasion.

Examples of available sanded plywood grades include:

Exterior Plywood – A-A, A-B, A-C, B-C, and C-C Plugged

Exposure 1 Plywood – N-N, N-A, N-B, N-D, A-A, A-B, A-D, B-B, B-D, Underlayment**, C-D Plugged**, Structural 1 C-D Plugged**

** Panels are touch-sanded. Other sanded grades may be available; contact manufacturer for availability.


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