Ceramic Tile IS Standards India: IS 15622, IS 13630, IS 13712 & BIS Marking Explained

When a bathroom tile fails on an Indian site — a floor tile that cracks under a dropped bucket, a wall tile that crazes, a "vitrified" tile that turns out to soak water — the argument almost always comes down to one question the drawings never answered: which standard was the tile supposed to meet? Tiles are one of the most heavily specified finishes in a bathroom, yet the Indian Standards behind them are widely misquoted. This guide is the reference: the real IS code numbers, what each covers, and the numbers a professional spec or quote should actually name.

This is the standards-reference guide in the Studio Matrx bathroom hub. Read it alongside the bathroom building regulations for India for the wider code picture, the bathroom wall tiles guide for selection, porcelain / vitrified bathroom tiles for the low-absorption family, and how to choose bathroom tiles for the buyer's shortlist.

Caveat first. Indian Standards are revised, and Quality Control Orders and municipal bye-laws change. The code numbers and figures below are the ones we are confident about at the date of writing, but verify the current edition of each IS, the applicable BIS Quality Control Order, and your local authority or a licensed professional before you rely on any of it in a contract or submission.

Why the standard belongs in the spec, not the showroom

A tile that looks identical on two shelves can belong to completely different performance classes. "Vitrified", "ceramic", "porcelain" and "GVT" are marketing words; the water-absorption class and the test certificate are the facts. A spec or quote that just says "vitrified floor tile, 600×600" leaves the contractor free to supply the cheapest tile that vaguely fits. A spec that says "tile to IS 15622, Group BIa (water absorption ≤ 0.5%), abrasion PEI Class IV minimum, bearing the ISI mark" is enforceable. The standards below are the vocabulary that makes that possible.

The core Indian Standards for tiles — reference table

These are the codes a bathroom tile specification in India actually turns on. Editions move, so treat the year as indicative and confirm the current version on the BIS catalogue.

Note the division of labour: IS 13712 defines the language, IS 15622 sets the pass/fail specification, and IS 13630 is the laboratory rulebook that says how each property is measured. You cannot invoke one sensibly without the others.

Water-absorption groups — the heart of IS 15622

Every ceramic tile is graded by how much water its fired body absorbs, expressed as a percentage of dry weight. Lower absorption means a denser, stronger, less porous body — which is exactly what a wet bathroom floor needs. IS 15622, harmonised with ISO 13006, sorts dry-pressed ("Group B") tiles as follows.

Two things trip people up. First, the leading "B" is the forming method — dry-pressed — not a grade; extruded tiles carry an "A". IS 15622 is the dry-pressed specification, which is what almost all Indian bathroom tiles are. Second, BIa (≤ 0.5%) is what dealers call "vitrified" — the same low-absorption body the rest of the world calls porcelain. If a bathroom floor spec does not name a group, it is not really specified. For a wet Indian floor, insist on BIa, and treat BIII strictly as a dry-wall tile.

Alongside the absorption class, IS 15622 sets minimum mechanical limits per group. For a fully vitrified BIa tile the standard fixes an indicative modulus of rupture of about 35 N/mm² and, for tiles 7.5 mm thick or more, a breaking strength of roughly 1300 N — the numbers that separate a floor-grade tile from a wall-grade one. Confirm the exact limits in the current edition before quoting them in a contract.

IS 13630 — the test-method rulebook

IS 13630 is not one document but a multi-part series, each part a separate laboratory method. It is what a test certificate cites when it reports a tile's performance. The properties the series governs include:

• Water absorption — the boiling/vacuum method that places a tile in its BIa–BIII group.
• Breaking strength and modulus of rupture — the three-point bending test behind the floor-versus-wall distinction.
• Resistance to surface abrasion — the basis of the PEI class for glazed tiles (see below).
• Resistance to deep abrasion — for unglazed tiles, reported as removed volume in mm³.
• Chemical resistance and stain resistance — against household acids, alkalis and cleaners.
• Thermal shock, crazing and thermal expansion — durability under temperature swings.
• Dimensions and surface quality — length, width, thickness, straightness, flatness.

When a supplier hands you a "test report", it should reference the relevant IS 13630 parts, not just assert a pass. We deliberately do not list individual part numbers here — the series has been re-numbered across editions and pinning the wrong part erodes trust. Ask the lab report to name the parts it used and cross-check them against the current BIS catalogue.

IS 13712 and the ISO 13006 alignment

IS 13712 supplies the definitions and classification — it is the dictionary that IS 15622 speaks. It sets out the forming methods (dry-pressed "B", extruded "A"), the water-absorption groups, and the characteristics a tile is described by. India's tile standards are technically harmonised with ISO 13006, the international standard for "Ceramic tiles — Definitions, classification, characteristics and marking". That is why the BIa/BIb/BIII group codes you see on an Indian box match the ISO group codes on an imported one: they come from the same framework. For imports and for specifying to a global brand, quoting ISO 13006 alongside IS 15622 keeps the two systems aligned. If you are unsure whether a specific Indian adoption of ISO 13006 exists under a given number, cite ISO 13006 and IS 15622/IS 13712 by name rather than inventing an equivalence.

PEI abrasion and slip resistance — the two numbers a floor spec needs

Two performance parameters decide whether a tile is safe and durable underfoot, and both are commonly under-specified.

PEI abrasion class. The Porcelain Enamel Institute (PEI) rating grades the wear resistance of a glazed tile's surface on a five-class scale, measured by the surface-abrasion method within IS 13630:

• PEI Class I — walls only, no foot traffic.
• PEI Class II — light traffic, e.g. bathrooms with soft footwear.
• PEI Class III — moderate traffic, most residential floors.
• PEI Class IV — heavier traffic, residential and light commercial.
• PEI Class V — heavy commercial traffic.

For a residential bathroom floor, PEI III–IV is a sensible minimum; unglazed full-body vitrified is rated by deep abrasion instead and does not carry a PEI class.

Slip resistance. This is where Indian specs are weakest, because a single dominant IS slip test has not been the norm. In practice, tile slip performance is specified using internationally recognised measures: the German DIN 51130 ramp test (R-ratings R9–R13, for shod feet) and DIN 51097 (barefoot classes A/B/C for wet areas), or a dynamic coefficient of friction (DCOF) value. For a wet bathroom floor, aim for around R10–R11 or a DCOF of 0.42 or higher, and keep polished surfaces out of the wet zone. Treat these as indicative targets and confirm the test method with the manufacturer — see the bathroom wall tiles guide and how to choose bathroom tiles for how this plays into selection.

The ISI / BIS mark — and mandatory certification

The ISI mark is the visible sign that a product is made under a BIS licence to a specified Indian Standard — for tiles, that is a licence to IS 15622. It means the manufacturer's process is audited and the product is sample-tested against the standard, not merely that the box quotes a code. On a tile, the marking should carry the IS number and the BIS licence number (a CM/L number).

Ceramic and vitrified tiles were brought under a mandatory BIS Quality Control Order (QCO), requiring the ISI mark on tiles sold in India — including imports — to their applicable IS specification. QCOs and their phased dates change, so verify the current QCO and its scope with BIS before treating certification as guaranteed for a given product or import. For a professional spec, the safe wording is to require the tile to bear a valid ISI mark to IS 15622 and to ask for the manufacturer's BIS licence number and a current IS 13630 test report.

What your spec or quote should reference

Pull it together into enforceable language. A bathroom tile line item that stands up on site names:

• The standard and group — e.g. "floor tile to IS 15622, Group BIa, water absorption ≤ 0.5%".
• The abrasion class — e.g. "PEI Class IV minimum" for glazed floor tiles.
• The slip target — e.g. "wet-zone floor R10–R11 / DCOF ≥ 0.42".
• The certification — "shall bear a valid ISI mark to IS 15622; supply BIS licence number and IS 13630 test report".
• The fixing standard — adhesive to IS 15477, laid and sloped per NBC 2016 workmanship — see the bathroom building regulations for India.

Specify those five and the tile can no longer be quietly substituted for a weaker, more porous one. Leave any of them blank and the standard stops protecting you.

References

• IS 15622 — Pressed ceramic tiles — Specification. Bureau of Indian Standards. (Water-absorption groups BIa–BIII, strength and flatness limits.)
• IS 13712 — Ceramic tiles — Definitions, classification and characteristics. Bureau of Indian Standards.
• IS 13630 — Ceramic tiles — Methods of test, sampling and basis for acceptance (multi-part series). Bureau of Indian Standards.
• ISO 13006 — Ceramic tiles — Definitions, classification, characteristics and marking. International Organization for Standardization.
• IS 15477 — Specification for polymer-modified cementitious tile adhesives. Bureau of Indian Standards.
• National Building Code of India (NBC 2016) — flooring, wall-finish and tiling workmanship provisions.
• BIS (Bureau of Indian Standards) — ISI marking, product certification licences and Quality Control Orders for ceramic tiles.