What is the difference between BWR and Interior grade coir blockboards?

BWR (Boiling Water Resistant) grade uses a phenolic synthetic resin adhesive, making it suitable for high humidity areas. Interior grade uses a urea formaldehyde resin and is meant for dry indoor applications only (Clause 4.4).

What are the standard available thicknesses for this board?

Standard thicknesses are 12, 15, 19, 22, 25, 30, 35, 40, 45, and 50 mm (Clause 6.1).

What is the minimum required screw holding strength?

The minimum average screw withdrawal strength is 1150 N on the face and 600 N on the edge (Table 2).

What are the dimensional tolerances for a standard board?

The tolerance on thickness is ±5%, and on length and width it is ±2.0 mm (Clause 6.2).

IS 15877

: 2010

Coir Faced Block Boards -Specification

CurrentSpecializedSpecificationBIMMaterials Science · Wood and Other Lignocellulosic Products

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This standard specifies the requirements for coir-faced blockboards, which are composite panels with a central core of wood strips, faced with coir mat and wood veneers. It covers materials, manufacturing, dimensions, physical and mechanical properties for both Boiling Water Resistant (BWR) and Interior grades, intended for use in furniture, partitions, and paneling.

Coir Faced Block Boards -Specification

Quick Reference Values

Moisture Content5 to 15 %

Adhesion of Plies (BWR Grade)Excellent

Modulus of Rupture (BWR, along grain, min)30 N/mm²

Modulus of Elasticity (BWR, along grain, min)3000 N/mm²

Screw Withdrawal Strength (Face, min)1150 N

Standard Thickness Range12 mm to 50 mm

Thickness Tolerance± 5 %

Practical Notes

Specify BWR grade for applications in kitchens, bathrooms, or areas with high humidity to prevent delamination.

The coir face provides excellent bonding for laminates and paints but may require a sealer or primer for a smooth finish.

Always check for the BIS Standard Mark (ISI mark) on the board to ensure it conforms to the standard's quality requirements.