Copper pipe is a mainstay in modern plumbing, HVAC, refrigeration, house and industrial applications due to its reliability, durability, and ease of use. When and how to choose the copper tubing for your project? Here we will help you out by breaking down copper pipe types, size charts, and practical advice for selection and installation, integrating detailed technical standards and real-world best practices.
What is Copper Pipe/Tubing?
Copper pipe is a seamless, non-ferrous metal tube made primarily from pure copper. It is widely recognized for its strength, corrosion resistance, and antimicrobial properties. In homes, copper tubing is commonly found supplying water, while in commercial and HVAC settings, it carries gases, refrigerants, or compressed air. Copper tubing is available in rigid straight lengths or flexible coils, with a range of wall thicknesses and diameters to suit many applications.
How Is Copper Tubing Made?
The manufacturing process begins with copper ore, which is mined and refined through smelting and electro-refining to achieve over 99.99% purity. The purified copper is melted and cast into billets or logs, which are then extruded through steel dies to form thick-walled mother tubes. These are further drawn out through progressively smaller dies, with intermittent annealing to control hardness and flexibility. The final tubing is inspected for thickness, leaks, and defects, then cut to length or coiled depending on intended use. The result is smooth, strong tubing ideal for plumbing, refrigeration, or electrical applications.
When & Where To Use Copper Pipe/Tubing?
Copper pipe remains a preferred choice for:
- Potable water supply: Its corrosion resistance and antimicrobial qualities make it ideal for drinking water.
- Heating systems: Copper’s thermal conductivity is beneficial in hydronic heating and radiator lines.
- Refrigeration & HVAC: Soft copper coils are used in air conditioning and refrigeration for their flexibility and leak-free reliability.
- Medical gas lines: Thicker-walled types are required for high-pressure or critical applications.
- Drainage and venting: Special copper types handle non-pressurized waste and vent lines.
Copper is not always the most cost-effective (compared to PEX), but its durability, reliability, and long lifespan keep it popular for new installations, repairs, and remodels—especially where local codes require metal piping or where high water velocity or aggressive water chemistry is a concern.
Copper Pipe/Tube Types (Color Codes/Uses)
Copper tubing is categorized by wall thickness and application, typically marked with color codes:
- Type K (Green) Copper Tubing: The thickest and most durable; used underground, for main water lines, and in commercial or industrial plumbing. It is often required where higher pressure or longevity is needed.
- Type L (Blue) Copper Tubing: Slightly thinner than Type K, but still robust. Type L is the most common choice for interior plumbing, repairs, and general water lines. It is suitable for both above-ground and underground installations.
- Type M (Red) Copper Tubing: Thinner wall than K or L; lighter and less expensive. Type M is intended primarily for heating systems (like hot water baseboards) and is permitted for potable water only in some regions due to potential erosion at high velocities.
- Type DWV (Yellow) Copper Tubing: Specifically for drain, waste, and vent (non-pressurized) lines. DWV pipe has the thinnest walls and is not used for water supply.
The color coding can usually be found stamped or painted along the length of the pipe, helping installers quickly identify the right type for a job.
Copper Pipe/Tube Standards
Copper pipe and tube standards vary by country, but the main ones include:
- ASTM B88 (USA): Covers Types K, L, and M for water and gas.
- EN 1057 (Europe): Defines copper and copper alloy tubes for water and gas in buildings.
- JIS H3300 (Japan): Standard for copper and copper alloy seamless pipes and tubes.
- GB/T 1527 (China): Copper and copper alloy drawn pipes and tubes.
These standards specify dimensions, wall thickness, tolerances, and physical properties, ensuring pipes fit fittings and perform as expected worldwide.
Standard Copper Pipe Sizes (OD, ID, Wall Thickness)
Copper tubing dimensions are specified by:
- Outside Diameter (OD): Measured across the pipe’s exterior (standard in HVAC/refrigeration).
- Inside Diameter (ID): OD minus 2 × wall thickness.
- Nominal Size (NS): Roughly corresponds to the inside diameter (ID); common in plumbing.
- Wall Thickness: Dictates the pressure rating and suitability for different purposes.
- Gauge: Sometimes used as an alternate measure of thickness.
- Weight per Meter: Useful for estimating loads and material requirements.
The sizes of copper pipes used in different environments are different. So copper pipes and tubes are manufactured in several standard sizes, depending on their intended use (plumbing, refrigeration, etc.) and the standards they follow (such as Type K, L, M, DWV for plumbing in North America, or metric sizes in other regions). Below are size charts for copper pipes used for different purposes (refrigeration, HVAC, water supply, plumbing), including the external dimensions and allowable deviations of air conditioning pipes, seamless copper water pipes, gas pipes, insulated copper pipes, and plastic-coated copper pipes.
Standard Copper Tube/Pipe Size Chart in MM & Inches
| Nominal Size (mm/in) | Actual OD (mm/in) | Common Wall Thickness (mm/in, Type) | Common Type(s) | Typical Use |
|---|---|---|---|---|
| Metric Copper Pipe/Tube Sizes (EN 1057, AS 1432, etc.) | ||||
| 6 mm | 6.0 / 0.236 | 0.7 / 0.028 (EN 1057) | EN 1057 | Capillary, instrumentation |
| 8 mm | 8.0 / 0.315 | 0.7 / 0.028 (EN 1057) | EN 1057 | Capillary, refrigeration |
| 10 mm | 10.0 / 0.394 | 1.0 / 0.039 (EN 1057) | EN 1057 | Plumbing, heating |
| 12 mm | 12.0 / 0.472 | 1.0 / 0.039 (EN 1057) | EN 1057 | Plumbing, heating |
| 14 mm | 14.0 / 0.551 | 1.0 / 0.039 (EN 1057) | EN 1057 | HVAC, specialty |
| 15 mm | 15.0 / 0.591 | 1.0 / 0.039 (EN 1057) | EN 1057 | Plumbing, heating |
| 16 mm | 16.0 / 0.630 | 1.0 / 0.039 (EN 1057) | EN 1057 | HVAC, specialty |
| 18 mm | 18.0 / 0.709 | 1.0 / 0.039 (EN 1057) | EN 1057 | Plumbing, heating |
| 20 mm | 20.0 / 0.787 | 1.0 / 0.039 (EN 1057) | EN 1057 | HVAC, specialty |
| 22 mm | 22.0 / 0.866 | 1.0 / 0.039 (EN 1057) | EN 1057 | Plumbing, heating |
| 25 mm | 25.0 / 0.984 | 1.0 / 0.039 (EN 1057) | EN 1057 | HVAC, specialty |
| 28 mm | 28.0 / 1.102 | 1.0 / 0.039, 1.2 / 0.047 (EN 1057) | EN 1057 | Plumbing, heating |
| 32 mm | 32.0 / 1.260 | 1.2 / 0.047 (EN 1057) | EN 1057 | Commercial, HVAC |
| 35 mm | 35.0 / 1.378 | 1.2 / 0.047 (EN 1057) | EN 1057 | Plumbing, heating, commercial |
| 40 mm | 40.0 / 1.575 | 1.2 / 0.047 (EN 1057) | EN 1057 | HVAC, specialty |
| 42 mm | 42.0 / 1.654 | 1.2 / 0.047 (EN 1057) | EN 1057 | Plumbing, heating, commercial |
| 50 mm | 50.0 / 1.969 | 1.5 / 0.059 (EN 1057) | EN 1057 | HVAC, specialty |
| 54 mm | 54.0 / 2.126 | 1.2 / 0.047 (EN 1057) | EN 1057 | Plumbing, heating, commercial |
| 60 mm | 60.0 / 2.362 | 1.5 / 0.059 (EN 1057) | EN 1057 | HVAC, specialty |
| 64 mm | 64.0 / 2.520 | 1.5 / 0.059 (EN 1057) | EN 1057 | Industrial, commercial |
| 67 mm | 67.0 / 2.638 | 1.5 / 0.059 (EN 1057) | EN 1057 | Industrial, commercial |
| 70 mm | 70.0 / 2.756 | 1.5 / 0.059 (EN 1057) | EN 1057 | HVAC, specialty |
| 76 mm | 76.0 / 2.992 | 1.5 / 0.059 (EN 1057) | EN 1057 | Industrial, commercial |
| 80 mm | 80.0 / 3.150 | 1.5 / 0.059 (EN 1057) | EN 1057 | Industrial, commercial |
| 88.9 mm | 88.9 / 3.500 | 2.0 / 0.079 (EN 1057) | EN 1057 | Industrial, commercial |
| 90 mm | 90.0 / 3.543 | 2.0 / 0.079 (EN 1057) | EN 1057 | HVAC, specialty |
| 100 mm | 100.0 / 3.937 | 2.0 / 0.079 (EN 1057) | EN 1057 | HVAC, specialty |
| 108 mm | 108.0 / 4.252 | 2.0 / 0.079 (EN 1057) | EN 1057 | Industrial, commercial |
| 133 mm | 133.0 / 5.236 | 2.5 / 0.098 (EN 1057) | EN 1057 | Industrial, commercial |
| 159 mm | 159.0 / 6.260 | 2.5 / 0.098 (EN 1057) | EN 1057 | Industrial, commercial |
| Imperial Copper Pipe/Tube Sizes (ASTM B88, US/Canada) | ||||
| 1/4 in | 6.35 / 0.250 | 0.89 / 0.035 (K), 0.81 / 0.032 (L), 0.71 / 0.028 (M) | K, L, M | Capillary, plumbing, instrumentation |
| 3/8 in | 9.53 / 0.375 | 1.24 / 0.049 (K), 0.89 / 0.035 (L), 0.71 / 0.028 (M) | K, L, M | Capillary, plumbing, instrumentation |
| 1/2 in | 12.70 / 0.500 | 1.24 / 0.049 (K), 1.02 / 0.040 (L), 0.71 / 0.028 (M) | K, L, M | Plumbing, water, gas |
| 5/8 in | 15.88 / 0.625 | 1.24 / 0.049 (K), 1.02 / 0.040 (L), 0.71 / 0.028 (M) | K, L, M | Plumbing, water, gas |
| 3/4 in | 19.05 / 0.750 | 1.65 / 0.065 (K), 1.14 / 0.045 (L), 0.81 / 0.032 (M) | K, L, M | Plumbing, water, gas |
| 1 in | 25.40 / 1.000 | 1.65 / 0.065 (K), 1.27 / 0.050 (L), 0.89 / 0.035 (M) | K, L, M | Plumbing, water, gas |
| 1-1/4 in | 31.75 / 1.250 | 1.65 / 0.065 (K), 1.40 / 0.055 (L), 1.07 / 0.042 (M) | K, L, M | Plumbing, water, gas |
| 1-1/2 in | 38.10 / 1.500 | 1.83 / 0.072 (K), 1.52 / 0.060 (L), 1.24 / 0.049 (M) | K, L, M | Plumbing, water, gas |
| 2 in | 50.80 / 2.000 | 2.11 / 0.083 (K), 1.78 / 0.070 (L), 1.47 / 0.058 (M) | K, L, M | Plumbing, water, gas |
| 2-1/2 in | 63.50 / 2.500 | 2.41 / 0.095 (K), 2.03 / 0.080 (L), 1.70 / 0.067 (M) | K, L, M | Plumbing, water, gas |
| 3 in | 76.20 / 3.000 | 2.77 / 0.109 (K), 2.29 / 0.090 (L), 1.83 / 0.072 (M) | K, L, M | Plumbing, water, gas |
| 3-1/2 in | 88.90 / 3.500 | 2.03 / 0.080 (L), 1.65 / 0.065 (M) | L, M | Plumbing, water, gas |
| 4 in | 101.60 / 4.000 | 3.40 / 0.134 (K), 2.79 / 0.110 (L), 2.41 / 0.095 (M) | K, L, M | Plumbing, water, gas |
| 5 in | 127.00 / 5.000 | 3.81 / 0.150 (K), 3.40 / 0.134 (L), 2.77 / 0.109 (M) | K, L, M | Plumbing, water, gas |
| 6 in | 152.40 / 6.000 | 4.19 / 0.165 (K), 3.58 / 0.141 (L), 3.12 / 0.123 (M) | K, L, M | Plumbing, water, gas |
| 8 in | 203.20 / 8.000 | 4.78 / 0.188 (K), 4.19 / 0.165 (L), 3.58 / 0.141 (M) | K, L, M | Plumbing, water, gas |
Type K Copper Pipe/Tube Size Chart (MM/Inches)
| Nominal Size (in) | Nominal Size (mm) | Outside Diameter (in) | Outside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|---|---|
| 1/4″ | 6 | 0.375 | 9.53 | 0.035 | 0.89 | 0.145 | 0.216 |
| 3/8″ | 10 | 0.500 | 12.70 | 0.049 | 1.24 | 0.269 | 0.400 |
| 1/2″ | 13 | 0.625 | 15.88 | 0.049 | 1.24 | 0.344 | 0.512 |
| 5/8″ | 16 | 0.750 | 19.05 | 0.049 | 1.24 | 0.418 | 0.622 |
| 3/4″ | 20 | 0.875 | 22.23 | 0.065 | 1.65 | 0.641 | 0.954 |
| 1″ | 25 | 1.125 | 28.58 | 0.065 | 1.65 | 0.839 | 1.249 |
| 1-1/4″ | 32 | 1.375 | 34.93 | 0.065 | 1.65 | 1.04 | 1.548 |
| 1-1/2″ | 40 | 1.625 | 41.28 | 0.072 | 1.83 | 1.36 | 2.025 |
| 2″ | 50 | 2.125 | 53.98 | 0.083 | 2.11 | 2.06 | 3.066 |
| 2-1/2″ | 65 | 2.625 | 66.68 | 0.095 | 2.41 | 2.92 | 4.346 |
| 3″ | 80 | 3.125 | 79.38 | 0.109 | 2.77 | 4.00 | 5.952 |
| 3-1/2″ | 90 | 3.625 | 92.08 | 0.120 | 3.05 | 5.12 | 7.621 |
| 4″ | 100 | 4.125 | 104.78 | 0.134 | 3.40 | 6.51 | 9.694 |
| 5″ | 125 | 5.125 | 130.18 | 0.160 | 4.06 | 9.67 | 14.393 |
| 6″ | 150 | 6.125 | 155.58 | 0.192 | 4.88 | 13.87 | 20.639 |
| 8″ | 200 | 8.125 | 206.38 | 0.271 | 6.88 | 25.9 | 38.54 |
| 10″ | 250 | 10.125 | 257.18 | 0.338 | 8.59 | 40.3 | 59.97 |
| 12″ | 300 | 12.125 | 307.98 | 0.405 | 10.29 | 57.8 | 86.04 |
Type L Copper Pipe/Tube Size Chart (MM/Inches)
| Nominal Size (in) | Nominal Size (mm) | Outside Diameter (in) | Outside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|---|---|
| 1/4″ | 6 | 0.375 | 9.53 | 0.030 | 0.76 | 0.126 | 0.187 |
| 3/8″ | 10 | 0.500 | 12.70 | 0.035 | 0.89 | 0.198 | 0.295 |
| 1/2″ | 13 | 0.625 | 15.88 | 0.040 | 1.02 | 0.285 | 0.424 |
| 5/8″ | 16 | 0.750 | 19.05 | 0.042 | 1.07 | 0.362 | 0.539 |
| 3/4″ | 20 | 0.875 | 22.23 | 0.045 | 1.14 | 0.455 | 0.677 |
| 1″ | 25 | 1.125 | 28.58 | 0.050 | 1.27 | 0.655 | 0.974 |
| 1-1/4″ | 32 | 1.375 | 34.93 | 0.055 | 1.40 | 0.884 | 1.315 |
| 1-1/2″ | 40 | 1.625 | 41.28 | 0.060 | 1.52 | 1.140 | 1.698 |
| 2″ | 50 | 2.125 | 53.98 | 0.070 | 1.78 | 1.75 | 2.604 |
| 2-1/2″ | 65 | 2.625 | 66.68 | 0.080 | 2.03 | 2.48 | 3.690 |
| 3″ | 80 | 3.125 | 79.38 | 0.090 | 2.29 | 3.33 | 4.953 |
| 3-1/2″ | 90 | 3.625 | 92.08 | 0.100 | 2.54 | 4.29 | 6.385 |
| 4″ | 100 | 4.125 | 104.78 | 0.110 | 2.79 | 5.38 | 8.008 |
| 5″ | 125 | 5.125 | 130.18 | 0.125 | 3.18 | 7.61 | 11.327 |
| 6″ | 150 | 6.125 | 155.58 | 0.140 | 3.56 | 10.20 | 15.187 |
| 8″ | 200 | 8.125 | 206.38 | 0.200 | 5.08 | 19.30 | 28.736 |
| 10″ | 250 | 10.125 | 257.18 | 0.250 | 6.35 | 30.10 | 44.789 |
| 12″ | 300 | 12.125 | 307.98 | 0.280 | 7.11 | 40.40 | 60.158 |
Type M Copper Pipe/Tube Size Chart (MM/Inches)
| Nominal Size (in) | Outside Diameter (in) | Outside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|---|
| 1/4″ | 0.375 | 9.53 | 0.025 | 0.64 | 0.106 | 0.158 |
| 3/8″ | 0.500 | 12.70 | 0.025 | 0.64 | 0.144 | 0.214 |
| 1/2″ | 0.625 | 15.88 | 0.028 | 0.71 | 0.203 | 0.302 |
| 5/8″ | 0.750 | 19.05 | 0.028 | 0.71 | 0.263 | 0.391 |
| 3/4″ | 0.875 | 22.23 | 0.032 | 0.81 | 0.328 | 0.488 |
| 1″ | 1.125 | 28.58 | 0.035 | 0.89 | 0.464 | 0.690 |
| 1-1/4″ | 1.375 | 34.93 | 0.042 | 1.07 | 0.681 | 1.014 |
| 1-1/2″ | 1.625 | 41.28 | 0.049 | 1.24 | 0.940 | 1.399 |
| 2″ | 2.125 | 53.98 | 0.058 | 1.47 | 1.46 | 2.173 |
| 2-1/2″ | 2.625 | 66.68 | 0.065 | 1.65 | 2.03 | 3.022 |
| 3″ | 3.125 | 79.38 | 0.072 | 1.83 | 2.68 | 3.988 |
| 3-1/2″ | 3.625 | 92.08 | 0.083 | 2.11 | 3.58 | 5.329 |
| 4″ | 4.125 | 104.78 | 0.095 | 2.41 | 4.66 | 6.935 |
| 5″ | 5.125 | 130.18 | 0.109 | 2.77 | 6.66 | 9.912 |
| 6″ | 6.125 | 155.58 | 0.122 | 3.10 | 8.91 | 13.262 |
| 8″ | 8.125 | 206.38 | 0.170 | 4.32 | 16.50 | 24.547 |
| 10″ | 10.125 | 257.18 | 0.212 | 5.39 | 25.60 | 38.095 |
| 12″ | 12.125 | 307.98 | 0.254 | 6.45 | 36.70 | 54.641 |
Type DWV Copper Pipe/Tube Size Chart
| Nominal Size (in) | Outside Diameter (in) | Outside Diameter (mm) | Inside Diameter (in) | Inside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|---|---|---|
| 1-1/4″ | 1.375 | 34.93 | 1.295 | 32.89 | 0.040 | 1.02 | 0.650 | 0.968 |
| 1-1/2″ | 1.625 | 41.28 | 1.541 | 39.15 | 0.042 | 1.07 | 0.809 | 1.204 |
| 2″ | 2.125 | 53.98 | 2.041 | 51.85 | 0.042 | 1.07 | 1.070 | 1.593 |
| 3″ | 3.125 | 79.38 | 3.035 | 77.09 | 0.045 | 1.14 | 1.690 | 2.517 |
| 4″ | 4.125 | 104.78 | 4.009 | 101.83 | 0.058 | 1.47 | 2.870 | 4.271 |
| 5″ | 5.125 | 130.18 | 4.981 | 126.53 | 0.072 | 1.83 | 4.43 | 6.596 |
| 6″ | 6.125 | 155.58 | 5.959 | 151.37 | 0.083 | 2.11 | 6.10 | 9.079 |
| 8″ | 8.125 | 206.38 | 7.907 | 200.84 | 0.109 | 2.77 | 10.6 | 15.78 |
ACR Copper Pipe/Tube Sizes for Refrigeration (ASTM B280 Standard)
| Nominal Size (inches) | Temper | Outside Diameter (in) | Outside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Inside Diameter (in) | Inside Diameter (mm) | Weight (lb/ft) | Weight (kg/m) | Cross Sectional Area (in²) | Volume (gal/ft) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/8 | A | 0.125 | 3.18 | 0.030 | 0.762 | 0.065 | 1.65 | 0.0347 | 0.0516 | 0.0033 | 0.00015 |
| 3/16 | A | 0.187 | 4.75 | 0.030 | 0.762 | 0.128 | 3.25 | 0.0575 | 0.0856 | 0.0129 | 0.00067 |
| 1/4 | A | 0.250 | 6.35 | 0.030 | 0.762 | 0.190 | 4.83 | 0.0804 | 0.120 | 0.0284 | 0.00150 |
| 5/16 | A | 0.312 | 7.92 | 0.032 | 0.813 | 0.248 | 6.30 | 0.109 | 0.162 | 0.0483 | 0.00255 |
| 3/8 | A | 0.375 | 9.52 | 0.032 | 0.813 | 0.311 | 7.90 | 0.134 | 0.199 | 0.076 | 0.00397 |
| 3/8 | D | 0.375 | 9.52 | 0.030 | 0.762 | 0.315 | 8.00 | 0.126 | 0.187 | 0.078 | 0.00404 |
| 1/2 | A | 0.500 | 12.70 | 0.032 | 0.813 | 0.436 | 11.10 | 0.182 | 0.271 | 0.149 | 0.00777 |
| 1/2 | D | 0.500 | 12.70 | 0.035 | 0.889 | 0.430 | 10.90 | 0.198 | 0.295 | 0.145 | 0.00756 |
| 5/8 | A | 0.625 | 15.88 | 0.035 | 0.889 | 0.555 | 14.10 | 0.251 | 0.374 | 0.242 | 0.01258 |
| 5/8 | D | 0.625 | 15.88 | 0.040 | 1.02 | 0.545 | 13.80 | 0.285 | 0.424 | 0.233 | 0.01213 |
| 3/4 | A | 0.750 | 19.05 | 0.035 | 0.889 | 0.680 | 17.30 | 0.305 | 0.454 | 0.363 | 0.01887 |
| 3/4 | A | 0.750 | 19.05 | 0.042 | 1.07 | 0.666 | 16.90 | 0.362 | 0.539 | 0.348 | 0.01812 |
| 3/4 | D | 0.750 | 19.05 | 0.042 | 1.07 | 0.666 | 16.90 | 0.362 | 0.539 | 0.348 | 0.01812 |
| 7/8 | A | 0.875 | 22.22 | 0.045 | 1.14 | 0.785 | 19.90 | 0.455 | 0.677 | 0.484 | 0.02516 |
| 7/8 | D | 0.875 | 22.22 | 0.045 | 1.14 | 0.785 | 19.90 | 0.455 | 0.677 | 0.484 | 0.02516 |
| 1-1/8 | A | 1.125 | 28.60 | 0.050 | 1.27 | 1.025 | 26.00 | 0.655 | 0.974 | 0.825 | 0.04290 |
| 1-1/8 | D | 1.125 | 28.60 | 0.050 | 1.27 | 1.025 | 26.00 | 0.655 | 0.974 | 0.825 | 0.04290 |
| 1-3/8 | A | 1.375 | 34.90 | 0.055 | 1.40 | 1.265 | 32.10 | 0.884 | 1.316 | 1.260 | 0.06550 |
| 1-3/8 | D | 1.375 | 34.90 | 0.055 | 1.40 | 1.265 | 32.10 | 0.884 | 1.316 | 1.260 | 0.06550 |
| 1-5/8 | A | 1.625 | 41.28 | 0.060 | 1.52 | 1.505 | 38.23 | 1.14 | 1.697 | 1.78 | 0.09280 |
| 1-5/8 | D | 1.625 | 41.28 | 0.060 | 1.52 | 1.505 | 38.23 | 1.14 | 1.697 | 1.78 | 0.09280 |
| 2-1/8 | D | 2.125 | 53.98 | 0.070 | 1.78 | 1.985 | 50.42 | 1.75 | 2.604 | 3.39 | 0.1610 |
| 2-5/8 | D | 2.625 | 66.68 | 0.080 | 2.03 | 2.465 | 62.61 | 2.48 | 3.692 | 4.97 | 0.2479 |
| 3-1/8 | D | 3.125 | 79.38 | 0.090 | 2.29 | 2.945 | 74.82 | 3.33 | 4.96 | 7.41 | 0.3542 |
| 3-5/8 | D | 3.625 | 92.08 | 0.100 | 2.54 | 3.425 | 87.00 | 4.29 | 6.39 | 9.97 | 0.4792 |
| 4-1/8 | D | 4.125 | 104.78 | 0.110 | 2.79 | 3.905 | 99.22 | 5.38 | 8.01 | 13.05 | 0.6238 |
Copper Tubing Size Chart for HVAC (ASTM B280)
| Nominal Size (in) | Temper | Outside Diameter (in / mm) | Inside Diameter (in / mm) | Wall Thickness (in / mm) | Weight (lb/ft / kg/m) | Tube Content (cu ft/ft / L/m) |
|---|---|---|---|---|---|---|
| 1/8 | A | 0.125 / 3.18 | 0.065 / 1.65 | 0.030 / 0.76 | 0.0347 / 0.052 | 0.00002 / 0.0021 |
| 3/16 | A | 0.187 / 4.75 | 0.128 / 3.25 | 0.030 / 0.76 | 0.0575 / 0.086 | 0.00009 / 0.0103 |
| 1/4 | A | 0.250 / 6.35 | 0.190 / 4.83 | 0.030 / 0.76 | 0.0804 / 0.120 | 0.00020 / 0.0212 |
| 5/16 | A | 0.312 / 7.92 | 0.248 / 6.30 | 0.032 / 0.81 | 0.109 / 0.162 | 0.00034 / 0.0365 |
| 3/8 | A | 0.375 / 9.52 | 0.311 / 7.90 | 0.032 / 0.81 | 0.134 / 0.200 | 0.00053 / 0.0571 |
| 3/8 | D | 0.375 / 9.52 | 0.315 / 8.00 | 0.030 / 0.76 | 0.126 / 0.188 | 0.00054 / 0.0581 |
| 1/2 | A | 0.500 / 12.70 | 0.436 / 11.07 | 0.032 / 0.81 | 0.182 / 0.271 | 0.00103 / 0.110 |
| 1/2 | D | 0.500 / 12.70 | 0.430 / 10.92 | 0.035 / 0.89 | 0.198 / 0.295 | 0.00101 / 0.108 |
| 5/8 | A | 0.625 / 15.88 | 0.555 / 14.10 | 0.035 / 0.89 | 0.251 / 0.374 | 0.00168 / 0.179 |
| 5/8 | D | 0.625 / 15.88 | 0.545 / 13.84 | 0.040 / 1.02 | 0.285 / 0.424 | 0.00162 / 0.173 |
| 3/4 | A | 0.750 / 19.05 | 0.680 / 17.27 | 0.035 / 0.89 | 0.305 / 0.454 | 0.00252 / 0.269 |
| 3/4 | D | 0.750 / 19.05 | 0.666 / 16.92 | 0.042 / 1.07 | 0.362 / 0.539 | 0.00242 / 0.258 |
| 7/8 | A | 0.875 / 22.23 | 0.785 / 19.94 | 0.045 / 1.14 | 0.455 / 0.677 | 0.00336 / 0.361 |
| 7/8 | D | 0.875 / 22.23 | 0.785 / 19.94 | 0.045 / 1.14 | 0.455 / 0.677 | 0.00336 / 0.361 |
| 1-1/8 | A | 1.125 / 28.58 | 1.025 / 26.04 | 0.050 / 1.27 | 0.655 / 0.974 | 0.00573 / 0.614 |
| 1-1/8 | D | 1.125 / 28.58 | 1.025 / 26.04 | 0.050 / 1.27 | 0.655 / 0.974 | 0.00573 / 0.614 |
| 1-3/8 | A | 1.375 / 34.93 | 1.265 / 32.13 | 0.055 / 1.40 | 0.884 / 1.316 | 0.00875 / 0.938 |
| 1-3/8 | D | 1.375 / 34.93 | 1.265 / 32.13 | 0.055 / 1.40 | 0.884 / 1.316 | 0.00875 / 0.938 |
| 1-5/8 | A | 1.625 / 41.28 | 1.505 / 38.23 | 0.060 / 1.52 | 1.14 / 1.697 | 0.0124 / 1.324 |
| 1-5/8 | D | 1.625 / 41.28 | 1.505 / 38.23 | 0.060 / 1.52 | 1.14 / 1.697 | 0.0124 / 1.324 |
| 2-1/8 | D | 2.125 / 53.98 | 1.985 / 50.42 | 0.070 / 1.78 | 1.75 / 2.604 | 0.0215 / 2.297 |
| 2-5/8 | D | 2.625 / 66.68 | 2.465 / 62.61 | 0.080 / 2.03 | 2.48 / 3.692 | 0.0331 / 3.535 |
| 3-1/8 | D | 3.125 / 79.38 | 2.945 / 74.82 | 0.090 / 2.29 | 3.33 / 4.955 | 0.0473 / 5.054 |
| 3-5/8 | D | 3.625 / 92.08 | 3.425 / 87.00 | 0.100 / 2.54 | 4.29 / 6.388 | 0.0640 / 6.840 |
| 4-1/8 | D | 4.125 / 104.78 | 3.905 / 99.23 | 0.110 / 2.79 | 5.38 / 8.008 | 0.0833 / 8.893 |
Copper Pipe Sizes for Plumbing
| Nominal Size (in) | Outside Diameter (in) | Outside Diameter (mm) | Wall Thickness (in) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 1/8 | 0.375 (9.52) | 9.52 | 0.030 (0.762) | 0.762 | 0.126 |
| 3/16 | 0.437 (11.11) | 11.11 | 0.030 (0.762) | 0.762 | 0.149 |
| 1/4 | 0.500 (12.7) | 12.7 | 0.030 (0.762) | 0.762 | 0.172 |
| 5/16 | 0.562 (14.29) | 14.29 | 0.030 (0.762) | 0.762 | 0.194 |
| 3/8 | 0.625 (15.88) | 15.88 | 0.030 (0.762) | 0.762 | 0.218 |
| 1/2 | 0.750 (19.05) | 19.05 | 0.032 (0.813) | 0.813 | 0.289 |
| 5/8 | 0.875 (22.22) | 22.22 | 0.035 (0.889) | 0.889 | 0.374 |
| 3/4 | 1.000 (25.4) | 25.4 | 0.035 (0.889) | 0.889 | 0.430 |
| 7/8 | 1.125 (28.58) | 28.58 | 0.042 (1.067) | 1.067 | 0.543 |
| 1 | 1.250 (31.75) | 31.75 | 0.049 (1.245) | 1.245 | 0.662 |
| 1 1/8 | 1.375 (34.93) | 34.93 | 0.049 (1.245) | 1.245 | 0.735 |
| 1 1/4 | 1.500 (38.1) | 38.1 | 0.049 (1.245) | 1.245 | 0.803 |
| 1 3/8 | 1.625 (41.28) | 41.28 | 0.049 (1.245) | 1.245 | 0.871 |
| 1 1/2 | 1.750 (44.45) | 44.45 | 0.049 (1.245) | 1.245 | 0.940 |
| 1 5/8 | 1.875 (47.63) | 47.63 | 0.049 (1.245) | 1.245 | 1.008 |
| 2 | 2.125 (53.98) | 53.98 | 0.049 (1.245) | 1.245 | 1.148 |
Copper Pipe Sizes for Water Supply (Seamless Water/Gas Pipe)
| Nominal Diameter (mm) | Average Outside Diameter (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|
| 6 | 8.0 ± 0.10 | 1.0 ± 0.10 | 0.116 |
| 8 | 10.0 ± 0.10 | 1.0 ± 0.10 | 0.146 |
| 10 | 12.0 ± 0.10 | 1.0 ± 0.10 | 0.176 |
| 15 | 16.0 ± 0.10 | 1.0 ± 0.10 | 0.238 |
| 20 | 20.0 ± 0.10 | 1.0 ± 0.10 | 0.302 |
| 25 | 25.0 ± 0.10 | 1.0 ± 0.10 | 0.380 |
| 32 | 32.0 ± 0.12 | 1.2 ± 0.12 | 0.572 |
| 40 | 40.0 ± 0.15 | 1.5 ± 0.15 | 0.884 |
| 50 | 50.0 ± 0.15 | 1.5 ± 0.15 | 1.116 |
| 65 | 63.0 ± 0.20 | 2.0 ± 0.16 | 1.844 |
| 80 | 75.0 ± 0.20 | 2.0 ± 0.16 | 2.205 |
| 100 | 89.0 ± 0.25 | 2.5 ± 0.20 | 3.189 |
| 125 | 108.0 ± 0.25 | 3.0 ± 0.24 | 4.258 |
| 150 | 133.0 ± 0.30 | 3.0 ± 0.24 | 5.308 |
| 200 | 159.0 ± 0.40 | 3.0 ± 0.24 | 6.323 |
| 219 | 219.0 ± 0.50 | 4.0 ± 0.32 | 11.899 |
| 325 | 325.0 ± 0.60 | 5.0 ± 0.40 | 19.738 |
| 426 | 426.0 ± 0.72 | 6.0 ± 0.48 | 30.948 |
| 508 | 508.0 ± 0.96 | 7.0 ± 0.56 | 41.353 |
| 610 | 610.0 ± 0.96 | 7.0 ± 0.56 | 49.846 |
| 711 | 711.0 ± 0.96 | 8.0 ± 0.64 | 61.008 |
Standard Copper Tubes Wall Thicknesses for Different Uses
Copper pipes commonly used in piping systems can be divided into two typical categories based on their application.
In the refrigeration and air conditioning industry, copper pipes are mainly made of pure copper, with the TP2 grade being most prevalent for indoor air conditioner connection lines. The typical diameter range is 3 to 19 mm, with wall thicknesses divided into three national standard levels:
- Standard pipes: Minimum 0.46 mm
- Thin-walled pipes: Starting from 0.30 mm
- Thick-walled pipes: Up to 0.81 mm
Threaded copper pipes with a diameter of 9.5 mm are commonly used in split-type air conditioners, where the thin-walled model is about 0.4 mm thick.
For domestic water supply and drainage systems, copper water pipes are widely used, with diameters similar to PPR pipes. National standards require the pipe to meet pressure-bearing requirements.
Taking DN15 copper pipe as an example:
- Thin-walled models with a 1 mm wall thickness are suitable for low-rise residential buildings.
- For mid-rise buildings, a reinforced type with 1.5 mm wall thickness is used.
- For main water supply lines in buildings, a strengthened type with wall thickness above 2 mm is typical.
In new hospitals, international grade C122 is often selected, and DN20 hot water pipes commonly use a 2.5 mm wall thickness.
Copper condenser fittings for appliances follow multiple standards. For example, the internationally accepted specification for 9 mm diameter copper pipe takes into account the charging pressure of refrigerants, and the industry generally recommends a wall thickness between 1.2 and 1.8 mm. In U.S. HVAC codes, the high-pressure HW type in R410A systems must use a 2.0 mm standard thickness to pass burst tests.
Industrial circulation systems require special selections. In one petrochemical plant’s reflux unit, a 76 mm diameter heat-conducting copper pipe was produced with a 3.5 mm ultra-thick wall via cold rolling to withstand scouring by 12 m/s flow rates. In new energy vehicles, bimetallic copper pipes with composite inner linings are used in electronic circulation cooling, with a base copper layer of 1.2 mm covered by reinforcement, achieving a 34% weight reduction.
European Union building standards have dedicated classifications. For example, Type-A flanged drinking water pipes with a 14 mm diameter require a tested wall thickness of no less than 1.85 mm and a weight tolerance limit of 7%. For medical-grade gas delivery, special requirements specify that the wall thickness tolerance for straight pipes made from dual-phase copper must be within 0.06 mm.
Attention to selection standards in practical use is important. In one wastewater treatment project, ammonia removal system rework revealed that pressure failure occurred because the owner illegally substituted 0.5 mm thick refrigeration pipe for the standard TP2 high-pressure water pipe. In another project acceptance meeting, supervision pointed out that the product certificate provided by the installer showed wall thickness deviation exceeding the GB code by 5%, leading to the material being ruled non-compliant.
Material mechanical properties result in differing outcomes. One testing laboratory showed that 0.8 mm thick forged seamless steel pipes reached the crack resistance grade of 1.5 mm laser-welded pipes. It is recommended that for high-temperature pipelines subject to complex cyclic stresses, thin-walled, high-strength copper pipes manufactured by precision forging processes should be prioritized. Users should determine the optimal wall thickness range based on the fluid’s corrosiveness, pressure values, and service life requirements, consulting authoritative industry selection tables for accurate data.
How To Measure/Determine Copper Pipe/Tube Size?
There are a few reliable methods to determine copper pipe size:
- Check Pipe Markings:
Many pipes have size and thickness printed or stamped along their length. - Measure Outside Diameter (OD):
Use a tape measure or caliper to measure the OD. For example, a pipe with a 28.6 mm OD is typically a 1-1/8 inch copper pipe. - Measure Circumference:
Wrap a tape measure around the pipe to get the circumference, then divide by π (3.14) to find the diameter.- Example: A 90 mm circumference ÷ 3.14 = 28.6 mm OD.
- Check Inner Diameter (ID):
For plumbing, the nominal size is often close to the internal diameter—measure across the pipe opening from inside wall to inside wall. - Reference the Weight:
Sometimes, the weight per meter helps confirm the size.
What is the Most Common Copper Pipe Size?
In residential water supply systems, the most frequently used copper pipe sizes are:
- 1/2 inch (15 mm OD): Common for branch lines to individual fixtures.
- 3/4 inch (22 mm OD): Often used for main supply lines and larger branches.
- 1 inch (28 mm OD): Used for main lines in larger homes or where higher demand exists.
These sizes are practical for most household needs, balancing ease of installation and adequate flow.
What Size Copper Pipe for Shower?
For a typical shower, a 1/2 inch copper pipe is usually sufficient, as it can handle up to 4 fixture units (according to the Uniform Plumbing Code). If the shower features high-flow heads or multiple outlets, or if the run is unusually long, a 3/4 inch supply may be recommended for optimal pressure.
What Size Copper Pipe for Water Lines?
- Branch lines to fixtures (sink, toilet, shower):
1/2 inch is standard. - Main water supply line:
3/4 inch is common for most homes; 1 inch may be needed for larger houses or higher demand. - Commercial or multi-unit buildings:
Larger sizes (1 inch and up) are used for main supplies.
Sizing should also account for the total number of fixtures, developed length of piping, elevation changes, and available water pressure.