Grade follows the room, thickness follows the span

Most homes get furnished with one grade of plywood throughout. That single decision guarantees one of two outcomes: money wasted on bedrooms that never needed it, or a kitchen that fails early because it got an interior-grade board.

Specifying room by room takes an extra twenty minutes and usually costs less overall. Here is the whole house.

Two decisions, kept apart

• Grade follows moisture exposure. It is a water rating, not a quality ranking.
• Thickness follows span and load. It has nothing to do with grade.

Confusing the two is why people buy Marine-grade board for a bookshelf that then sags.

Going room by room

Bedrooms

Grade: MR (IS:303). Ambient humidity only — exactly what MR is designed for.

Element	Thickness
Wardrobe carcass and dividers	19 mm
Wardrobe shutters	19 mm
Shelves (2.5 ft span)	19 mm
Bed frame, headboard	19 mm
Side tables, dressers	19 mm
Back panels	12 mm
Loft storage	19 mm

Where the money should actually go: 19 mm shutters rather than 16 mm, edge banding on all four edges of every shutter, and a balancing finish on the inside face of laminated panels. Detail in best plywood for wardrobes.

Living room

Grade: MR.

The characteristic problem here is span. Living-room shelving tends to be wide and lightly supported for visual reasons, which is precisely the geometry that sags.

Element	Thickness	Note
TV unit carcass	19 mm
Display shelving under 2.5 ft	19 mm
Display shelving 3–4 ft	25 mm or supported	Lip the front edge
Open shelving over 4 ft	Block board, or add a divider
Seating bases, storage benches	19 mm	Sat on — do not reduce
Wall panelling	6–12 mm	On a batten framework
Back panels	12 mm

Wall panelling is the one place to genuinely go thin. Thin board on battens looks better and moves less than heavy sheets fixed flat to a wall.

Kitchen

Grade: BWR for the working run and shutters, BWP under the sink.

This is the room where under-specifying has a predictable cost, and the only room where the grade decision is not negotiable.

Element	Grade	Thickness
Under-sink carcass and base	BWP	19 mm
Base units, working run	BWR	19 mm
Upper cabinets	BWR	19 mm
All shutters	BWR	19 mm
Internal shelves	BWR	19 mm
Back panels, drawer bottoms	BWR	12 mm

Plus: raise the plinth off the floor, ventilate the rear of base units, seal every site cut. Full treatment in best plywood for a modular kitchen.

Bathrooms and vanities

Grade: BWR outside splash range, BWP within it.

Bathrooms are a small area with a high failure rate, for two reasons: the room stays damp for long periods, and the furniture usually sits at floor level where water collects.

• Wall-hang the vanity if the design allows. Getting the carcass off the floor does more than any grade change.
• Seal the basin cut-out thoroughly.
• Ventilation matters as much as grade. A working extractor extends a vanity's life more than upgrading BWR to BWP does.
• Avoid plywood at skirting level in a bathroom entirely.

Utility area and balcony

Grade: BWP.

The most commonly forgotten space in a specification. Utility areas are frequently semi-open — a washing machine, a sink, a drying line, and a wall open to weather. That is a cyclical wetting environment and it is harder on a board than a kitchen.

If a balcony unit is genuinely exposed to rain rather than merely to humidity, ask whether plywood is the right material at all, or whether the design should shelter it.

Study, pooja room and storage

Grade: MR.

Element	Thickness	Note
Study table top	25 mm	Or 19 mm on a supporting frame
Bookshelves	19 mm	Books are heavy; keep spans under 2.5 ft
Storage units	19 mm
Pooja unit	19 mm
Loft / overhead storage	19 mm	Fix into the wall, not the unit below

Bookshelves deserve a note: books are among the heaviest things put on a domestic shelf, and bookshelf spans are often designed for looks. Keep them short or accept a visible bow.

Doors. Flush doors are a distinct product — a solid-core panel built as a door rather than cut from sheet material. For internal doorways in dry rooms a standard flush door is appropriate; for a bathroom door, ask specifically about the core and the treatment, because the bottom edge of a bathroom door lives in a wet zone.

The whole house, in one table

Room	Grade	Structural elements	Thin elements
Bedroom	MR	19 mm	12 mm
Living room	MR	19 mm (25 mm long spans)	6–12 mm panelling
Kitchen — general	BWR	19 mm	12 mm
Kitchen — under sink	BWP	19 mm	—
Bathroom vanity	BWR / BWP	19 mm	12 mm
Utility, balcony	BWP	19 mm	12 mm
Study, pooja, storage	MR	19 mm (25 mm tops)	12 mm
Wall panelling	MR	—	6–12 mm

Five details that beat the brand name

1. Seal every cut edge, on every element, including the ones nobody sees.
2. Finish both faces of any shutter or panel, or it will cup.
3. Match thickness to span, especially on shelves.
4. Order in one or two lots — batch consistency shows on adjacent shutters.
5. Store flat and off the floor before the carpenter starts.

Four of the five are free. They prevent more furniture failures than any grade upgrade.

Buying for a whole house

Two arguments for buying an entire interior from one production run: adjacent elements match in thickness and shade, and a repeat order for a forgotten unit is more likely to match.

For a whole-house interior, pre-cut supply is worth costing. Site wastage often exceeds 15% because parts get cut one at a time from whichever sheet is nearest. Panels nested and cut to a list at the factory reduce both material and site time.

Lennor Ply manufactures MR, BWR, BWP, Marine and FR grades in Hassan, Karnataka, alongside block boards, flush doors and laminates from the same line — useful when a house needs all four to match.

Rates, lead times and delivery: contact us.

Questions we get asked

Which plywood is best for home interiors? MR grade for dry rooms, BWR for kitchens and bathrooms, BWP for under-sink units, utility areas and balconies. One grade throughout is almost always the wrong answer.

What plywood should I use for bedroom furniture? MR grade (IS:303) at 19 mm for carcasses, shutters and shelves, 12 mm for back panels. Bedrooms see ambient humidity only.

What plywood is best for living room furniture? MR grade at 19 mm, moving to 25 mm or adding support for shelving spans over three feet. Sag is the usual complaint in living-room furniture.

What thickness of plywood is used for wall panelling? 6–12 mm on a batten framework. Heavier sheets fixed flat to a wall look worse and move more.

Can I use MR plywood in a bathroom? No. Use BWR outside splash range and BWP within it, and wall-hang the vanity if possible.

How much plywood does a full home interior need? It depends entirely on how much built-in furniture is planned. List every element, convert to square feet, divide by 32 for 8 × 4 sheets and add 10–15% for wastage.

Talk to us

Send a floor plan or furniture list and we will return a room-by-room grade and thickness specification you can hand to a contractor.

Ask Lennor Ply.