Sanitaryware IS Standards India: IS 2556, IS 774, IS 771 & the ISI Mark (2026)

Two wash basins can look identical on a showroom shelf and be worlds apart in the fired body underneath the glaze. One is a properly vitrified piece that will shrug off twenty years of hard water; the other is an under-fired, porous body that will craze, stain and eventually weep. The only way to tell them apart before you buy — short of a laboratory — is the small mark stamped on the underside: the BIS ISI mark and the Indian Standard number it certifies against. This guide is a professional reference to those standards: which code governs which appliance, what each one actually tests, and what "compliant" means in numbers.

It sits under the bathroom building regulations for India, which frames the wider code landscape — the National Building Code, plumbing and water-supply codes, accessibility rules. Here we go deep on one slice of that landscape: the product standards for the ceramic and metal appliances themselves. For the fixtures in use, pair it with the toilet guide and the wash basin guide; for the finishes on the walls and floor, see the companion bathroom tile IS standards guide.

A standard is not paperwork — it is the difference between a body that is vitrified and one that only looks it. The ISI mark is your only pre-purchase proof.

The core standards at a glance

Indian sanitaryware is governed by the Bureau of Indian Standards (BIS), which publishes the IS-series specifications. A handful of codes do most of the work. The table below is the reference you will come back to — a code, the appliances it covers, and the headline requirement it enforces.

Two things to read into this table. First, IS 2556 is a multi-part standard, not a single document: Part 1 sets the general requirements that apply to every vitreous china appliance, and the later parts add the specific requirements for each fixture type. When a data sheet says a basin conforms to "IS 2556", it means the general part plus the relevant appliance part together. Second, product standards and practice standards are different things — IS 2556 tells you whether the object is sound; IS 2064 and IS 1172 tell you how many to provide and how to install them.

IS 2556 — vitreous china appliances

Vitreous china is the workhorse material of the Indian bathroom: the white, glass-hard ceramic used for almost every mass-market wash basin, water closet, squatting pan and urinal. IS 2556 is the family of standards that governs it. Part 1 lays down the general requirements every piece must meet, and the subsequent parts add fixture-specific rules — wash-down water closets, squatting pans, wash basins, urinals and sinks each have their own part with their own dimensions and performance tests.

What Part 1 controls is the quality of the fired body and glaze:

• Water absorption — the single most important number. A properly vitrified china body absorbs not more than 0.5% of its weight in water. Low absorption is what makes the piece impervious, stain-resistant and hygienic; a porous, under-fired body will slowly soak up water, harbour bacteria and craze.
• Crazing resistance — fine hairline cracks in the glaze. Samples are subjected to a thermal-shock or autoclave test and must show no crazing afterwards. Crazing is where hard-water stains and mould get their first foothold.
• Warpage and distortion — the piece must be flat and true within tolerance so a basin sits level, a seat mates cleanly and a wall-hung fixture bolts flush. Firing warps ceramics; the standard caps how much.
• Glaze finish and freedom from defects — a continuous, non-porous, smooth glaze free of pinholes, blisters, crawling and specks beyond the permitted limits.
• Strength and load — appliances, particularly wall-hung types, are load-tested to confirm they will carry service loads safely.

For water closets, the appliance-specific parts add the tests that matter in use: a minimum water-seal depth (around 50 mm) to keep drain gases out of the room, and a flush / discharge performance test that confirms the pan clears its contents cleanly on a normal flush.

IS 774 — flushing cisterns

The cistern is a separate product with its own standard, IS 774 — flushing cisterns for water closets and urinals. It governs the discharge volume and the flushing action. This is the standard that has moved most in recent years under water-conservation pressure: the old single-flush 10-litre cistern has largely given way to dual-flush designs offering a reduced flush and a full flush — indicatively around 3 litres and 6 litres — so a compliant modern cistern both flushes effectively and saves water. When you specify a cistern, IS 774 conformance plus a dual-flush mechanism is the sensible baseline.

IS 771 — glazed fireclay

IS 771 covers glazed fireclay sanitary appliances. Fireclay is a coarser, tougher ceramic than vitreous china, fired thick and finished with a heavy glaze. It is used where size and robustness matter more than the fine finish of china — large laboratory and kitchen-scale sinks, channel and cleaner's sinks, and some heavy-duty urinals and channels in institutional buildings. Fireclay bodies are more porous than vitreous china, so IS 771 sets its requirements around glaze soundness and coverage rather than the sub-0.5% absorption expected of china. Match the standard to the material: do not judge a fireclay sink against a china absorption figure.

Waste fittings and taps

An appliance is only as good as what drains and feeds it. IS 2963 covers copper alloy waste fittings for wash basins and sinks — the waste coupling and overflow fitting, their dimensions, threads and finish. Chromium-plated brass taps sit under separate BIS specifications for copper-alloy taps and fittings for water services. When you assemble a basin, three standards meet: the china body (IS 2556), the waste (IS 2963) and the tap. Buying a certified basin and pairing it with an uncertified waste is a common way to reintroduce the leak you were trying to design out.

Reading the quality — what "compliant" looks like

You will rarely run these tests yourself, but you should know what they check so you can inspect a delivered piece and read a test certificate. The table below turns the standards into a site checklist.

The ISI mark — your one pre-purchase proof

The ISI mark is the certification mark of the BIS. On a sanitary appliance it is moulded or stamped on the underside or an unglazed foot, and it carries two things: the IS number the product is certified against and the manufacturer's CM/L licence number (the licence that authorises that factory to use the mark). Without both, you have a piece that may or may not meet the standard and no way to know. Because build quality in ceramics is invisible under the glaze, the mark is the single most useful thing you can check before money changes hands.

Sanitaryware has increasingly been brought under mandatory BIS certification through Quality Control Orders, meaning certain sanitary appliances must legally carry the ISI mark to be sold. The exact list of covered products and effective dates change over time, so treat "is it under mandatory certification" as a question to verify on the current BIS position for the specific appliance rather than an assumption.

Practical guidance for specifiers:

• Specify the standard by number in your BOQ — "vitreous china WC conforming to IS 2556, ISI-marked" — not just "branded sanitaryware".
• Inspect on delivery, not after fixing. Check the mark, run a straightedge across the base for warpage, hold the piece to the light for pinholes and crazing.
• Keep the material honest — judge china against china standards (IS 2556) and fireclay against IS 771; do not mix the benchmarks.
• Certify the whole assembly — body, cistern, waste and tap each have a standard; specify all of them.

Codes and their parts are revised, and BIS mandatory-certification lists and local municipal bye-laws change. Verify the current edition of each Indian Standard on the BIS catalogue, and confirm requirements with your local authority or a licensed professional, before relying on anything here for a live project.

References

• IS 2556 — Vitreous sanitary appliances (vitreous china): Part 1 general requirements, with further parts for specific appliances (wash-down water closets, squatting pans, wash basins, urinals, sinks), Bureau of Indian Standards
• IS 771 — Glazed fireclay sanitary appliances (general requirements and specific parts), Bureau of Indian Standards
• IS 774 — Flushing cisterns for water closets and urinals, Bureau of Indian Standards
• IS 2963 — Copper alloy waste fittings for wash basins and sinks, Bureau of Indian Standards
• IS 2064 — Selection, installation and maintenance of sanitary appliances — code of practice, Bureau of Indian Standards
• IS 1172 — Code of basic requirements for water supply, drainage and sanitation, Bureau of Indian Standards
• Bureau of Indian Standards — ISI certification (Standard Mark) scheme and product Quality Control Orders

Verify every code number, part and edition against the current BIS catalogue before use; standards are periodically revised.