GI (Galvanised Iron) and Copper pipes are the traditional metal plumbing pipes. Although CPVC / UPVC plastic pipes have largely replaced them in residential water supply, GI and copper still have important roles — GI for exposed / mechanically-demanding lines, fire-fighting and outdoor risers; copper for premium water supply, medical gas, refrigeration and solar / gas lines. They offer mechanical strength and high-temperature capability that plastics cannot match.
Indian metal pipes are governed by IS 1239 (GI / MS tubes), IS 3589 (large steel pipes), IS 12818 / IS 9293 (copper tubes). Major brands: Tata Steel (GI), Jindal, APL Apollo, Surya Roshni (GI); Mehta Tubes, Maksal, Mandev, Totaline (copper).
| Parameter | GI Pipe | Copper Pipe |
|---|---|---|
| Material | Mild steel + zinc galvanising | Pure copper (99.9%) |
| Corrosion Resistance | Moderate (zinc wears off) | Excellent |
| Lifespan | 15–25 years | 50–70+ years |
| Max Temperature | High (steel) | Very high |
| Joining | Threaded | Brazing / soldering / press |
| Cost | Moderate | High (premium) |
| Water Quality | Scaling over time | Antimicrobial, pure |
| Use | Exposed, fire lines, structural | Premium supply, gas, medical, AC |
GI pipes are mild steel tubes coated inside & out with a layer of zinc (galvanising) to resist corrosion. They are strong, can be threaded, and handle high pressure and temperature.
| Class | Colour Band | Wall Thickness | Use |
|---|---|---|---|
| Light (Class A) | Yellow | Thinnest | Low pressure, gas, conduit |
| Medium (Class B) | Blue | Medium | Water supply (most common) |
| Heavy (Class C) | Red | Thickest | High pressure, fire lines, risers |
15 mm (1/2"), 20 mm (3/4"), 25 mm (1"), 32 mm (1-1/4"), 40 mm (1-1/2"), 50 mm (2"), 65, 80, 100, 150 mm.
Copper pipes are made from high-purity copper, prized for durability, corrosion resistance, and antimicrobial properties. Used in premium plumbing, medical gas, refrigeration (AC/R), gas lines and solar water heating.
| Type | Wall | Form | Use |
|---|---|---|---|
| Type K | Thickest | Hard / soft | Underground, medical, high pressure |
| Type L | Medium | Hard / soft | Water supply (common premium) |
| Type M | Thin | Hard | Domestic water (light) |
| ACR / Refrigeration | Special | Soft coil | AC, refrigeration, gas |
| Medical Gas | Cleaned | Hard | Hospitals (O2, vacuum) |
Copper sizes: 1/4", 3/8", 1/2", 5/8", 3/4", 1", up to large diameters; sold in straight lengths (hard) or coils (soft).
| Property | GI Pipe | Copper Pipe |
|---|---|---|
| Density | 7850 kg/m³ | 8960 kg/m³ |
| Tensile Strength | 320–400 MPa | 200–250 MPa |
| Melting Point | ~1500 °C | 1085 °C |
| Thermal Conductivity | 50 W/m.K | 400 W/m.K (high) |
| Coefficient of Expansion | 12 x 10−6 /°C | 17 x 10−6 /°C |
| Corrosion Resistance | Moderate (zinc layer) | Excellent |
| Antimicrobial | No | Yes |
| Recyclability | Yes | Excellent (high value) |
| Lifespan | 15–25 yr | 50–70 yr |
| Brand | Products |
|---|---|
| Tata Steel | Tata GI Pipes & Tubes |
| Jindal (Hisar) | Jindal GI Pipes |
| APL Apollo | Apollo GI & structural tubes |
| Surya Roshni | Surya GI Pipes |
| Mehta Tubes | Mehta Copper Tubes |
| Maksal | Maksal Copper Tubes |
| Mandev Tubes | Copper / ACR tubes |
| Totaline / Mexflow | ACR copper coils |
| Rajco / Multimetals | Copper tubes |
| Pipe / Size | Cost (Rs per m) |
|---|---|
| GI Medium 15 mm (1/2") | 90 – 160 |
| GI Medium 25 mm (1") | 180 – 320 |
| GI Heavy 50 mm (2") | 420 – 750 |
| Copper Type L 1/2" | 350 – 600 |
| Copper Type L 3/4" | 500 – 850 |
| Copper Type L 1" | 700 – 1200 |
| ACR Copper Coil 1/4" (per m) | 180 – 320 |
| ACR Copper Coil 1/2" (per m) | 350 – 600 |
Copper prices track LME rates. GI prices track steel + zinc.
| Standard | Description |
|---|---|
| IS 1239 (Part 1–2) | Steel Tubes, Tubulars & Fittings (GI / MS) |
| IS 3589 | Steel Pipes for Water & Sewage (large dia) |
| IS 4736 | Hot-Dip Zinc Coating on Steel Tubes |
| IS 12818 | Copper Tubes for Plumbing |
| IS 9293 | Copper Tubes for Refrigeration & AC |
| IS 191 | Copper (material specification) |
| IS 2501 | Solid Drawn Copper Tubes |
| ASTM B88 | Seamless Copper Water Tube (Type K/L/M) |
| ASTM B280 | ACR Copper Tube |
| IS 2065 | Code of Practice for Water Supply in Buildings |
GI and copper pipes remain important where strength, high temperature or premium quality matter. Use GI (medium class) for exposed and fire lines, heavy class for high pressure; use copper (Type L) for premium potable supply and ACR copper for AC / refrigeration / gas. Critically, never join GI directly to copper (galvanic corrosion) — use a dielectric union. For everyday concealed water supply, modern CPVC / UPVC is usually more economical and scale-free.
These pipes feed faucets, taps & showers, toilets, wash basins and kitchen sinks, supplied from tanks via geysers.