Birch Interior

Birch Interior is a premium choice for fine woodworking and cabinetry. Built from 100% European Birch throughout every layer, it offers exceptional strength and stability, making it highly resistant to bending and warping.

This lightweight, durable panel is bonded with a urea-formaldehyde (MR), interior-grade adhesive, which keeps its edges light in color and easy to machine. The natural, hard-surfaced birch grain provides an attractive finish that doesn’t require an overlay, making it ideal for furniture, shelving, and interior decorative projects.

Birch Interior meets strict formaldehyde emission standards (E1, CARB, and EPA TSCA Title VI), so you can be confident in its safety for indoor use.

Available exclusively in 5′ x 5′ sheets.

Properties

Key Benefits

Grading

Specifications


Thickness	1/4″ (6 mm), 3/8″ (9 mm), 1/2″ (12 mm), 5/8″ (15 mm), 3/4″ (18 mm), 7/8″ (21 mm), 15/16″ (24 mm), 1-1/16″ (27 mm), 1-3/16″ (30 mm), 1-3/8″ (35 mm), 1-9/16″ (40 mm)
Panel Size Available	5′ x 5′ (1525 mm x 1525 mm)
Glue	Interior – Urea formaldehyde adhesive (MR)
Formaldehyde Emissions	E 1, CARB ULEF
Grades	В/ВВ, ВВ/ВВ, ВB/CP, BB/C, CP/CP, CP/C, C/C
Surface Type	Outer layers sanded (S2S); Non Sanded available upon request
Moisture Content	5-14%
Water Resistance	High
Density (kg/m³)	640–700
Size Tolerance	Must not exceed 2mm
Slant	Must not exceed 2mm
Deviation from edges straightness	Must not exceed 2mm

Strength Indicators

Parameter	Thickness, mm	Value, MPa
Static bending strength, min
Along the grain of the face veneers	6.5–40	45
Across the grain of the face veneers	6.5–40	30
Tensile strength along the grain, min
Along the grain	2.7–6.5	30
Modulus of elasticity in static bending, min
Along the grain	6.5–40	7000
Across the grain	6.5–40	3000

Key Benefits

Grading

To ensure consistency and quality, it’s classified into four distinct grades—B/BB, BB/BB, BB/CP, and CP/C—each reflecting the appearance and allowable defects on the face and back veneers. Understanding these grades helps buyers match the right panel to their project’s aesthetic and structural demands.

Grade B

Highest grade of Baltic Birch Plywood, permitting minimal splits and ruling out any need for repairs. B represents face and BB back veneer. The face veneers are characterized by clarity and a defect-free, light, uniform color. On the back side, allowance is made for 3-6 color-matched patches. The inner cores, comprising solid birch single-piece veneers, reinforce its structural integrity. Surface is sanded intended for natural finish. This grade is often used in applications where the plywood will be visible, and a cleaner and more refined appearance is desired.

Allowable Defects

Non-Allowable Defects

Pin knot

Light knot

Loose knot

Pinhole

Burl

Light inbark

Dark inbark

Sound discoloration (congested streaks)

Swirly grain

Streak traces

Water stains

Close shakes

Knots with bark inclusions, knot holes

MR (interior glue) plywood over sanding

WBP (exterior glue) plywood oversanding

Delamination

Overlap

Patch

Waviness (sanded plywood), rough saw cut, ripple

Posted veneer chips

Metal inclusions

Bark patch

Coarse peeling

Shears (defects caused by cutting)

Grade BB

Second highest quality in Baltic Birch grade system. Both face and back sides allow color-matched patches, while knots and open defects are repaired with veneer inserts. The inner cores, comprising solid birch single-piece veneers, reinforce its structural integrity. Surface is sanded.

Allowable Defects

Non-Allowable Defects

Pin knot

Swirly grain

Pinhole

Dark knot

Close shakes

Streak traces

Sander skips (uneven sanding)

Overlap ridges (telegraphing overlaps)

Patch

Double patch

Pockets (without bark inclusions)

Sound discoloration (false heartwood)

Hollow

Gum hollow

Knots with bark inclusions, knot holes

MR (interior glue) plywood oversanding

WBP (exterior glue) plywood oversanding

Posted veneer chips

Waviness (sanded plywood), rough saw cut, ripple

Metal inclusions

Delamination

Bark patch

Blister

Discoloration with partial wood damage

Grade C

Patches, open knots, and minor veneer splits are acceptable. Veneer lap and small core voids are allowed. This panel is intentionally unsanded, but with guaranteed strong gluing properties, this grade is ideal for various structural applications.

Allowable Defects

Non-Allowable Defects

Dark inbark

Shake filling and sealing with inserts and putty

Shears (defects caused by cutting)

Dark knot with a shake

Gum hollow

MR (interior glue) plywood oversanding

WBP (exterior glue)

Overlap

Patch without color matching

Saw cut

Black knot

Dark intergrown knot

Bark patch

Blister

Delamination

Discoloration with partial wood damage

Grade CP

CP grade is excluded from BB classification due to minor defects and increased streaking. Permissible occasional hairline splits of less than 0.5mm. Oval or round patches may or may not match the color of the base face veneer. Typically, there will be more patches per face compared to the BB grade. Surface is sanded. Grade CP/CP is designed and ideal for laminating applications.