Kitchens and bathrooms destroy the wrong plywood. Learn which grade to specify, how to protect the edges, and the mistakes that cause cabinets to swell.
Kitchens and bathrooms test plywood harder than any other room. Humidity, spills, steam and the occasional leak will find any weakness.
Choosing and installing the right board prevents the swelling, delamination and musty smell that ruin cabinets within a year or two.
Specify BWP plywood, not MR
For wet zones, boiling-water-proof (BWP) plywood — often called marine plywood — is the correct choice. Its phenolic resin survives prolonged moisture and steam.
MR-grade board, however cheap, is not built for this and will eventually fail. This is the one place not to economise on grade.
Protecting plywood after installation
Even the right grade needs care in how it is finished and fitted.
Seal every edge
Waterproof plywood can still absorb water through unsealed cut edges. Seal and edge-band every exposed edge, and seal raw cuts around sinks before fitting.
Most cabinet failures in Bangladeshi kitchens begin at a neglected edge, not the face of the board.
Guard against termites
Wet timber attracts pests. Use plywood that is both waterproof and treated against termites and borers, so the cabinet is protected on both fronts.
Installation checklist
Before your carpenter starts, confirm these points:
- BWP / marine-grade board for all carcasses near water.
- All edges sealed and banded, including hidden ones.
- Termite-treated plywood specified on the order.
- Adequate gap and ventilation behind units so trapped moisture can escape.
Frequently asked questions
Which plywood is best for kitchen cabinets?
BWP (marine-grade) plywood, because its phenolic resin survives steam and spills. BWR is the minimum for dry parts of the kitchen; MR is not suitable near the sink.
Is marine plywood fully waterproof?
The board's glue is boiling-water proof, but water can still enter through unsealed cut edges. Seal and edge-band every edge to keep it waterproof in use.
Why do plywood kitchen cabinets swell?
Usually because MR-grade board was used in a wet area, or because cut edges were left unsealed and absorbed water.
Can plywood be used in a bathroom?
Yes, if it is BWP plywood with every edge sealed, treated against termites, and fitted with a ventilation gap behind the unit.
Need help choosing the right board or door for your project?
Our team can recommend the correct grade, thickness and finish for your use — and quote it honestly.
Get in touch
