IS 4990 Shuttering Plywood: What the Standard Covers and What to Check on Site
– By Mayank Agrawal, CEO & Managing Director, Paam Group
Quick answer: IS 4990 is the Indian Standard for plywood used in concrete shuttering (formwork). It covers boiling-water-proof (BWP) bonding, preservative-treated veneers and the plain, coated or film faced surface, and it sets tests for glue strength, stiffness and thickness. When sheets reach your site, look for the IS 4990 marking, then check the thickness, edges, film and weight before the boards go into use.
What is IS 4990?
IS 4990 is the Bureau of Indian Standards (BIS) specification for plywood for concrete shuttering work. It is a separate standard from IS 303, which covers general purpose plywood for furniture and interiors.
Shuttering plywood has a harder life than furniture plywood. It has to carry wet concrete, take vibration, survive stripping and go through repeated wetting and drying. So IS 4990 sets tougher requirements for the glue line and for the strength and stiffness of the whole board. BIS revises the standard from time to time, so refer to the current edition when you write it into a purchase specification.
Plain, coated and film faced shuttering plywood
Every type of shuttering plywood uses BWP adhesive. The difference is the face, which decides the concrete finish and how well the board stands up to repeated pours.
| Face | What it is | Typical use |
|---|---|---|
| Plain | Shuttering plywood with no added surface layer | Foundations and concrete that will be hidden or plastered |
| Coated | A resin or polymer coating on the face | General RCC work with a moderate finish |
| Film faced | Phenolic film pressed onto both faces | Slabs, beams, columns and walls where a smooth finish matters |
Most RCC work on building sites in India uses film faced shuttering plywood, because the film gives a smooth finish, releases cleanly and protects the face across pours.
What does IS 4990 test?
The standard sets laboratory tests that a manufacturer’s boards have to pass. The ones that matter most on site are:
- Glue shear strength, dry and after boiling. The boil test shows whether the glue line will hold after repeated wetting. A weak glue line is what makes boards delaminate.
- Moisture content of the finished board, within a set range.
- Stiffness and strength (modulus of elasticity and modulus of rupture), which decide how much the board deflects under wet concrete.
- Thickness tolerance, so that panels sit flush and the concrete surface stays even.
- Preservative treatment of the veneers against fungus and borers.
- Surface quality of the coating or film.
What to check when shuttering plywood sheets arrive
You cannot run a boil test on site, but you can catch most problems at the gate:
- Marking. Look for the IS 4990 marking on the sheet, along with the manufacturer’s details, size and batch.
- Thickness. Measure with a vernier at a few points on several sheets. It should match the thickness you ordered.
- Edges. They should be sealed, with no gaps or voids between the veneers.
- Film. It should be even, with no bare patches, bubbles or lifted corners.
- Weight. A heavier sheet usually has a denser core, but a wet board also weighs more, so use weight only as a rough guide alongside the checks above.
For a large order, ask your supplier for test reports for the batch.
IS 4990 shuttering plywood vs normal plywood
Normal plywood made for furniture and interiors (IS 303, often MR grade) uses glue that is not designed for long contact with water. On a slab it swells, the veneers separate and the concrete finish suffers, often within a pour or two. Shuttering plywood to IS 4990 uses BWP glue throughout, so it keeps its shape and bond through repeated wetting. That is why it costs more per sheet, and why it is usually cheaper per pour.
Does IS 4990 say how many times a board can be reused?
No. The standard sets material and test requirements, not a reuse count. How many pours you get depends on the grade and, above all, on site care: sealing cut edges, oiling before every pour, stripping and cleaning gently, and storing sheets flat and covered. Our guide to storing and using shuttering plywood on site covers each step.
Key takeaways
- IS 4990 is the Indian Standard for shuttering plywood; IS 303 is for general purpose plywood.
- All shuttering plywood uses BWP glue. Film faced boards give the smoothest finish and the most pours.
- The boil test for glue strength is the key quality test.
- On site, check the marking, thickness, edges, film and weight before use.
- No standard sets a reuse count. Site care decides it.
Frequently asked questions
What is IS 4990?
IS 4990 is the Bureau of Indian Standards specification for plywood used in concrete shuttering. It covers the adhesive, veneer treatment and surface of the board, and sets tests for glue strength, stiffness and thickness.
Is IS 4990 the same as BWP plywood?
No. BWP (boiling-water-proof) describes the type of glue. IS 4990 is a full standard for shuttering plywood that requires BWP glue and also covers strength, stiffness, thickness, treatment and the surface.
What is the difference between IS 4990 and IS 303?
IS 4990 is for plywood used in concrete formwork. IS 303 is for general purpose plywood used in furniture and interiors. IS 303 plywood is not made for repeated contact with wet concrete.
Is Paam shuttering plywood IS 4990 marked?
Yes. Paam Group's film faced shuttering plywood carries the IS 4990 marking. Check the marking, size and batch on the sheets you receive.
How many times can IS 4990 shuttering plywood be reused?
The standard does not set a number. Reuse depends on the grade and on site care, especially edge sealing, oiling, cleaning and storage. Tell us your floor cycle and we will help you plan the sheet quantity.
Need help choosing the right shuttering plywood grade for your project? Talk to the Paam team or call +91-40-24615104.
About the author: Mayank Agrawal is CEO & Managing Director of Paam Group, which has supplied shuttering plywood and formwork materials to construction projects across India since 1982.
