FreePlywood Grades Explained: Cabinet, Furniture and Exterior
Plywood grades describe the quality of the face and back veneers, and sometimes the glue. Softwood plywood uses letters A to D for each face (A smooth, D with knot holes) plus an exposure rating, as in CDX. Hardwood plywood for cabinets uses AA to E for the face and 1 to 4 for the back, as in A-1 or B-2. Baltic birch uses B, BB, CP and C.
Plywood grades chart
| Grade | What you get |
|---|---|
| A (softwood) | Smooth, sanded and paintable; only small neat repairs. |
| B (softwood) | Solid surface; small knots and round repair plugs allowed. |
| C-plugged | Improved C: splits and holes filled. |
| C (softwood) | Knots up to 1 1/2 in, knot holes up to 1 in, small splits. |
| D (softwood) | Knots and knot holes up to 2 1/2 in: hidden layers only. |
| AA / A (hardwood) | Premium and good matched faces: cabinets and furniture. |
| B (hardwood) | Colour-matched face with small repairs. |
| C, D, E (hardwood) | Sound but unmatched or repaired faces: paint grade and utility. |
| 1–4 (hardwood back) | 1 sound, 2 repaired, 3 and 4 with open defects. |
| B, BB, CP, C (Baltic birch) | From nearly clear (B) to open defects (C). |
Exterior and interior plywood
| Rating | Glue and where it goes |
|---|---|
| Exterior | Fully waterproof glue: siding, outdoor projects. Marine is the top grade. |
| Exposure 1 (X) | Waterproof glue but lower-grade veneers: sheathing that is covered after construction. |
| Interior | Interior glue: furniture and cabinets kept dry. Most hardwood plywood. |
Which grade for which job
| Job | Grade |
|---|---|
| Clear-finished cabinets and furniture | Hardwood A-1 or A-2 (birch, maple, oak), or Baltic birch B/BB |
| Painted cabinets | Hardwood B-2 or C-2, MDF or combination core |
| Drawer boxes | Baltic birch BB, 12–15 mm (1/2–5/8 in) |
| Shop furniture and shelving | ACX, BCX or CDX |
| Roofs, walls, subfloors | CDX or rated sheathing |
| Boats and wet areas | Marine plywood, BS 1088 |
Advantages
- A grade tells you the face quality before you see the sheet
- Letting a hidden face be a lower grade saves money
Drawbacks
- Different systems for softwood, hardwood and Baltic birch
- Grades describe faces, not the core or the flatness
What it is used for
- Cabinet and furniture faces: hardwood A or B
- Painted projects: AC or BC softwood, or hardwood C
- Sheathing and subfloors: CDX and rated panels
- Outdoors: exterior and marine grades
Tips for working with Plywood grades
- Buy the face grade you need on one side only: an A-1 sheet costs more than an A-3 whose back is hidden.
- Look at the core edge too: a grade stamp does not show voids.
- For painted cabinets, a smooth MDF or combination core matters more than the face grade.
Frequently asked questions
What is cabinet grade plywood?
Hardwood plywood with an A or B face (birch, maple or oak) on a veneer or combination core, usually A-1, A-2 or B-2. It is flat and smooth enough for visible cabinet parts.
What grade of plywood for furniture?
A or B face hardwood plywood, or Baltic birch B/BB. For painted furniture, a C face or MDF-core plywood is enough.
What is BC and BCX plywood?
BC plywood is softwood plywood with a B face (smooth, small repairs) and a C back (small knots and splits). BCX adds X for exterior glue (Exposure 1). It is a good, cheap choice for painted shop furniture, shelving and utility cabinets.
What is the best grade of exterior plywood?
For permanently wet places, marine plywood (BS 1088). For outdoor projects that dry between rains, exterior A-C or B-C plywood sealed on all edges.
What does the X in CDX mean?
Exposure 1 glue: it survives being rained on during construction, but the panel is not meant to stay outside uncovered.
Furniture plans to build
All plans →
Related guides
How to Build a CabinetHow to build a cabinet from plywood, MDF or melamine, step by step: size it, make the cut list, cut and edge band, drill, assemble the box and fit the doors.MDF vs PlywoodMDF vs plywood for cabinets, shelves and doors: strength, sag, screw holding, paint finish, moisture, weight and cost compared, with the right use for each.OSB vs PlywoodOSB vs plywood compared: strength, stiffness, moisture, weight and cost, and which is better for subfloors, roof and wall sheathing, shelving and furniture.