STEEL

Chequered / Floor Plate

Steel plate with raised pattern for floors, stair treads

Also calledchequered platecheckered platetear drop platefloor platediamond plate
Definition

Chequered plate (also called diamond plate, treadplate, or anti-skid plate) is a steel plate with raised pattern of diamond or rectangular shapes on one face — providing slip-resistance for use as walkways, stairs, working platforms, and machine guards. Per IS 3502:1994 + IS 2062:2011, chequered plates are typically 4-12 mm thick with patterns of various sizes. Major Indian chequered-plate suppliers: SAIL, JSW, Tata Steel, ESSAR.

Standard chequered plate sizes: thicknesses 4, 6, 8, 10, 12 mm; widths 1000-1500 mm; lengths 3000-6000 mm. Pattern types: small diamond (typical 35 mm spacing), large diamond (50 mm), rectangular bar pattern. The raised pattern provides slip-resistance equivalent to a coefficient of friction 0.45-0.55 (vs 0.30 for plain steel) — adequate for walking, equipment movement, and emergency egress. Applications: (1) Industrial walkways and stairs (most common Indian use); (2) Machine guards and equipment access platforms; (3) Vehicle ramps and loading dock surfaces; (4) Bridge inspection walkways; (5) Manufacturing facility working platforms.

Where used
  • Industrial walkways and stairs
  • Machine guards and equipment access platforms
  • Vehicle ramps and loading dock surfaces
  • Bridge inspection walkways
  • Manufacturing facility working platforms
Acceptance / threshold
Per IS 3502:1994 + IS 2062: pattern dimensions and spacing per specification; thickness ±10%; surface clean and free of defects; mill test certificate for material grade.
Site example
Site reality: a Hyderabad industrial plant used 8 mm chequered plate for crane operator walkways. Service life 15+ years with regular inspection. Compared to plain steel plate alternative: chequered provides better safety in oily / wet conditions; minor cost premium (5-10%). Always specify chequered plate for industrial walkways; safety improvement justifies the small cost increase.
Frequently asked
What is chequered plate?
Chequered plate (also called diamond plate, treadplate, anti-skid plate) is a steel plate with raised pattern of diamond or rectangular shapes on one face — providing slip-resistance. Per IS 3502:1994. Typical thicknesses 4-12 mm; patterns typically 35-50 mm spacing. Coefficient of friction 0.45-0.55 vs 0.30 for plain steel. Used for industrial walkways, stairs, machine guards.
What thickness of chequered plate is used?
Common: 4 mm (light duty walkways, equipment guards), 6 mm (general industrial walkways), 8 mm (heavy-duty, with light vehicle access), 10-12 mm (loading docks, heavy equipment platforms). Thickness selection depends on load: pedestrian only (4-6 mm), pedestrian + small equipment (6-8 mm), heavy equipment (10-12 mm).
Why use chequered plate?
Anti-slip surface: coefficient of friction 0.45-0.55 vs 0.30 for plain steel, providing safer walking surfaces in industrial environments. Self-cleaning — debris and water drain through the pattern. Aesthetic — clean industrial appearance. Cost premium over plain steel: 5-15%. Always specify for industrial walkways; safety improvement justifies the small cost increase.
Related steel terms
TMT Steel Bar (Fe415/Fe500/Fe550)
Thermo Mechanically Treated bars per IS 1786. Fe500 most common.
Lap Length
Length of overlap to transfer force between bars (40-60d typical)
Development Length / Anchorage
Length of bar embedment to develop full strength
Bar Bending Schedule (BBS)
Schedule listing bar shapes, sizes, lengths per IS 2502
Rebar Weight Calculation
Weight = D²/162.2 kg/m where D is dia in mm
Structural Steel Sections
ISMB/ISLB/ISWB/ISHB beams, ISMC channels, ISA angles per IS 808
ISMB (Indian Standard Medium Beam)
Indian Standard Medium Weight Beam — most common I-section
ISLB (Indian Standard Light Beam)
Indian Standard Light Weight Beam