What does CDX plywood mean?

CDX is the most common construction-grade plywood. C refers to the front face grade (knots up to 1-1/2 inches, minor splits), D refers to the back face grade (larger knots and defects), and X means the glue is rated for exterior exposure. CDX is used for roof sheathing, wall sheathing, and subflooring. It can handle temporary moisture during construction but is not rated for permanent outdoor exposure without protection. What is the best plywood for cabinets?

What is the best plywood for cabinets?

For cabinet boxes, use 3/4-inch hardwood plywood (maple or birch face) with veneer core or combination core. MDF core provides the flattest surface for painted cabinets. For drawer boxes, Baltic birch plywood is the standard due to its void-free core, beautiful exposed edges, and exceptional strength. Expect to pay $50-$70 per sheet for standard hardwood plywood and $50-$90 for 3/4-inch Baltic birch. What is special about Baltic birch plywood?

What is special about Baltic birch plywood?

Baltic birch plywood is made entirely from birch veneer with no softwood or filler plies. It has a void-free core (no gaps or patches), more plies per thickness (13 plies in 3/4 inch vs 5-7 in standard plywood), and beautiful exposed edges that many woodworkers intentionally show. Standard sheets are 5x5 feet (not 4x8). It's the preferred plywood for drawer boxes, jigs, CNC projects, and furniture where edges are visible. Costs $50-$90 per 5x5 sheet in 3/4 inch.

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Woodworking & Lumber

Types of Plywood: Grades, Core Materials & Which to Use for Every Project

Lumberama Editorial Team, Panel Products & Plywood Specialists May 19, 2025 10 min read

Plywood Grades

Plywood has a two-letter grade (e.g., A-C, B-B) that describes the quality of the two faces (front and back).

A grade: Smooth, sanded, minimal defects. Suitable for visible, painted surfaces. May have small, neatly made repairs. The premium face grade.

B grade: Solid surface with minor defects. Tight knots up to 1 inch, minor patches. Suitable for surfaces that will be painted or covered.

C grade: Knots up to 1-1/2 inches, some splits and patches. Not suitable for visible surfaces. Used for structural and utility applications.

D grade: Larger knots, knotholes, splits. The lowest grade. Used only where the face won't be visible. Sheathing and subflooring.

Common grade combinations: A-A (both faces premium — expensive), A-C (one good face for paint, rough back), B-C (utility with a reasonable face), C-D (CDX — the most common structural/sheathing grade).

Softwood Plywood

Made from Douglas fir, southern pine, or spruce veneer. Used primarily for construction and structural applications.

CDX: C-D grade with exterior (X) glue. The most common construction plywood. Used for roof sheathing, wall sheathing, and subflooring. Not truly waterproof — the X means the glue can handle temporary moisture exposure during construction, not permanent outdoor use.

Structural (rated sheathing): Stamped with span ratings (e.g., 32/16 means 32" rafter spacing for roofs, 16" joist spacing for floors). Sold in standard 4x8 sheets, 7/16" to 3/4" thick.

Exterior plywood: Fully waterproof glue with better face veneers (minimum C grade on both faces). For permanent outdoor use where both faces may be exposed to weather.

Hardwood Plywood

Decorative face veneer (oak, birch, maple, cherry, walnut) over a core material. Used for cabinets, furniture, shelving, and any application where the surface will be visible.

Veneer core: Traditional construction. Multiple thin wood plies (like softwood plywood). Strong, screw-holding, lighter weight. Good for structural applications. Can have minor core voids that show when edges are exposed.

MDF core: Hardwood veneer over a medium-density fiberboard core. Perfectly smooth, flat surfaces. No core voids. Heavier than veneer core. Excellent for painted cabinets and applications where flatness is critical. Downsides: very heavy, doesn't hold screws as well as veneer core, swells if exposed to water.

Combination core: MDF crossbands sandwiching a veneer core center. Combines the flatness of MDF with the lighter weight and screw-holding of veneer core. The premium option for high-end cabinetry.

Baltic Birch Plywood

A category of its own. Made in Russia, Finland, and the Baltic states from birch veneer throughout (no softwood or filler plies). Characteristics that make it special:

Void-free core: Every ply is solid birch with no gaps, patches, or voids. This means exposed edges are beautiful — a distinctive layered pattern that many woodworkers intentionally show as a design feature.

More plies: A 3/4" sheet has 13 plies (compared to 5-7 in standard plywood). More plies = more stability and strength.

Sheet size: Standard Baltic birch comes in 5x5 foot sheets (not 4x8). Some suppliers offer 4x8 sheets but they cost significantly more.

Uses: Drawer boxes, jigs and fixtures, speaker cabinets, CNC projects, furniture where edges will be visible, shop storage. The go-to plywood for woodworkers.

Price: $50-$90 for a 3/4" 5x5 sheet. More expensive than standard hardwood plywood per square foot.

Marine Plywood

The highest quality plywood made. Requirements: all-hardwood veneers (typically Douglas fir or okoume), waterproof glue, void-free core, A-A or A-B face grades.

Uses: Boat building, transom boards, outdoor furniture exposed to constant moisture, dock structures.

Note: Marine plywood is NOT pressure-treated and will still rot without finish protection. The waterproof designation means the glue won't fail when wet — the wood itself still needs protection from decay.

Price: $80-$200+ for a 4x8 sheet of 3/4". A premium product for premium applications.