Grades, densities and rates
| Grade | Density | Thickness | Rate (₹/sq ft) | Use |
|---|---|---|---|---|
| Standard WPC sheet | 550 – 650 kg/m³ | 18 mm | ₹95 – 145 | Bathroom vanity carcass, utility units |
| High density WPC | 650 – 750 kg/m³ | 18 mm | ₹140 – 200 | Kitchen base carcass in very wet locations |
| WPC door frame section | 700 – 800 kg/m³ | Profile | ₹320 – 550 / rft | Bathroom door frames; replaces timber entirely |
| WPC louvre / wall panel | 550 – 650 kg/m³ | 12 – 16 mm | ₹140 – 260 | Balcony and feature wall cladding |
| WPC decking plank | 900 – 1,100 kg/m³ | 22 – 25 mm | ₹220 – 400 | Terrace and balcony decking |
| Pre-laminated WPC | 600 – 700 kg/m³ | 18 mm | ₹160 – 240 | Ready-finished wet-area carcass |
Sheets are commonly 8 × 4 ft. An 18 mm sheet weighs roughly 28–34 kg depending on density.
Where WPC is the correct answer
- Bathroom vanity carcasses. The single best use. A vanity in a Mumbai bathroom is wet for a decade; WPC simply does not care, and it costs little more than good BWP ply.
- Bathroom door frames and shutters. A timber frame at a bathroom threshold rots at the bottom 100 mm. A WPC frame does not, and it takes paint and laminate normally.
- Balcony and open-to-sky joinery. Storage benches, planter boxes, utility cupboards. Sun and rain do nothing to it.
- Washing machine platforms and utility carcasses. Permanent standing water is normal there.
- Coastal ground-floor flats with rising damp history, where anything cellulose-based will eventually fail.
The three real weaknesses
- Sag. WPC creeps under sustained load more than ply. A 900 mm shelf in 18 mm WPC carrying weight will bow within a year. Keep spans under 600 mm or add a steel stiffener.
- Thermal movement. It expands measurably with temperature. On a balcony in direct sun, a 3 m run of WPC cladding will move several millimetres between morning and afternoon. Fix with slotted holes and leave expansion gaps.
- Screw holding. Fair in the face, poor in the edge and poor on re-insertion. Use coarse-thread screws, pilot-drill, and never rely on an edge screw for a hinge. For heavy doors, insert a ply or metal packer at hinge positions.
- Appearance. Raw WPC looks like plastic, because it largely is. It is a carcass and substrate material; the visible face should be laminate, acrylic or paint.
Mumbai use notes
- WPC has become the default vanity carcass in our bathroom specifications. The cost delta against BWP ply on a single vanity is ₹1,500–3,000, and it removes the commonest joinery failure in a Mumbai flat.
- It is heavier than it looks. A full-height WPC unit needs proper wall fixings; do not fix into a hollow block wall with plastic plugs alone.
- It cuts and machines like a soft board with standard tools, but it melts if the blade is blunt or the feed is slow. Sharp tooling and a steady feed.
- It accepts PVC edge banding and laminate normally, using the same adhesives. Standard contact adhesive bonds poorly — use a PVC-compatible adhesive and test on an offcut first.
- Do not use it as a countertop substrate under stone. The thermal movement and the creep will crack a stone slab over time.
Care, life and BOQ wording
- No maintenance beyond cleaning the finished surface. The board itself is inert.
- Expected life: 20 years or more in a wet area, where BWP ply would be showing wear at twelve.
- BOQ: “Vanity and utility carcasses in 18 mm WPC board, density not below 600 kg/m³; all exposed edges banded with 2 mm PVC; coarse-thread screws with pilot holes at all fixings.”
- BOQ: “Shelf spans in WPC limited to 600 mm clear; longer spans to include a concealed steel stiffener or be executed in BWP plywood.”
- BOQ: “External and balcony WPC cladding fixed with slotted holes and 3 mm expansion gaps at all joints.”
Specification summary
| Property | Specification |
|---|---|
| Density | 600 kg/m³ minimum; 700+ for door frames |
| Thickness | 18 mm carcass, 12–16 mm cladding |
| Water | Immune — no swelling, rot or borer |
| Shelf span | 600 mm maximum without a stiffener |
| Fixings | Coarse-thread screws, pilot drilled, face fixed |
| Rate | ₹95 – 220 per sq ft at 18 mm, ex-GST |
| Best use | Bathroom vanities, door frames, balcony and utility joinery |
| Avoid | Long loaded shelves, stone counter substrates, exposed finished faces |
Frequently asked questions
Is WPC better than plywood?+
In wet locations, yes — it cannot swell, rot or be eaten. Everywhere else, plywood is stiffer, holds screws better and costs less. The correct answer in a Mumbai flat is WPC for bathroom and balcony joinery and BWP ply for everything else.
Does WPC sag over time?+
Yes, under sustained load. It creeps more than plywood, so a long shelf will take a permanent bow. Keep clear spans to 600 mm, or build the shelf in ply and the carcass in WPC. This is the most common complaint about the material and it is entirely a design issue.
Can WPC be used for a full kitchen?+
It can, and some manufacturers promote it that way. We generally do not, because kitchen carcasses carry load and WPC creeps. Where a client has had a kitchen destroyed by water before, we build the base units in high-density WPC and the shelves in BWP ply.
Does WPC hold hinges and drawer runners?+
Adequately with coarse-thread screws into the face, and poorly into the edge. For heavy doors we insert a plywood or steel packer at the hinge positions. A soft-close hinge cycling thousands of times will eventually loosen an edge screw in WPC.
Is WPC fire resistant?+
It is a PVC composite and it is combustible, producing dense smoke. Flame-retardant grades exist. In commercial premises, check the landlord fit-out manual before using it for any wall lining or large surface area.