If you go to your local hardware or home store and look in the electrical aisle, you'll find EMT Conduit in a wide range of sizes and lengths. You may be surprised to learn that the listed size on the sticker doesn't actually refer to the inside or outside diameter. That is known as the trade size. In this blog we will briefly describe the trade size and then get the actual diameters of three common EMT Conduit sizes.
What Does The EMT Conduit Trade Size Mean?
Trade sizes can mean different things depending on the application. For example, PVC trade sizes refer to the inner diameter of the pipe whereas trade sizes of copper pipes refer to the outside diameter. This can be confusing especially if you're mainly looking to complete a desk or other DIY project and not actually running water or gas through your home.
Electricians use EMT Conduit to house cables and wires throughout industrial and commercial buildings. The trade size of EMT refers to the maximum bundle size that can fit in the pipe. For example, 1/2" EMT Conduit has an actual inner diameter of .622". The 1/2" measurement is letting you know that it's not recommended to run a bundle of wires larger than .50" through the conduit.
What You Need To Know For Building
For us DIYers and pipe builders, the trade size doesn't really matter unless you plan to run wires through the pipes in your project. What you really want to know is the inside and outside diameters of the conduit you're using. Knowing these measurements can help you find new accessories and solve specific challenges that may come up while you're working on your build.
What Are The Diameters Of 1/2" EMT Conduit?
What Are The Diameters Of 3/4" EMT Conduit?
What Are The Diameters Of 1" EMT Conduit?
Conclusion
Currently these are the three sizes of EMT Conduit that work with the maker Pipe Connectors. If you need the measurements of other EMT sizes check out this link here. Remember to keep an eye out for the trade size for the actual diameters when looking at all pipes and not just conduit. If you have any questions please don't hesitate to contact us. Thanks for reading and happy building.
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Electrical Metallic Tubing Data (Thinwall Conduit)
| Nominal Conduit Size Inches | Nominal Conduit Size mm | Conduit Inside Diameter Inches |
|---|
| 1/2" | 16 | 0.622 |
| 3/4" | 21 | 0.824 |
| 1" | 27 | 1.049 |
| 1-1/4" | 35 | 1.380 |
7 more rowsWhen choosing conduit, consider whether you need flexible or rigid conduit and whether it will be exposed to the elements. Like other tubes, conduit is measured by outside diameter. That diameter affects the internal diameter, which influences how much wire you'll be able to run through it.
What are standard conduit sizes? ›
Some typical US Customary trade sizes for conduit are ½, ¾, 1, and up to 4. Outside the US, conduit sizes are typically measured in millimeters and are based on the outer diameter. Some common metric outer diameter sizes are 20 mm, 25 mm, 32 mm, 40 mm and 50 mm.
What are the trade sizes for EMT? ›
EMT is available in trade sizes 1/2 through 4, and 10′ and 20′ lengths.
What are the 4 diameters of steel conduit? ›
Class 4 Steel Conduit 5 Items
- Class 4 Steel Conduit - Galv 20mm, 3.0mtr length. Heavy gauge steel conduit. ...
- Class 4 Steel Conduit - Galv 25mm, 3.0mtr length. ...
- Class 4 Steel Conduit - Galv 20mm, 3.75mtr length. ...
- Class 4 Steel Conduit - Galv 25mm, 3.75mtr length. ...
- Class 4 Steel Conduit - Galv 32mm, 3.75mtr length.
The most common diameters for conduits are 1/2 inch to 6 inches, and sizes are typically stated in inches. Larger sizes can also be ordered for particular commercial and industrial applications. Conduit size selection is influenced by various elements, including the kind and quantity of installed wiring.
How do you find the outside diameter of conduit? ›
Whether determining the external or internal diameter, utilizing a caliper ensures meticulous accuracy. For external diameter measurement, the caliper is positioned perpendicular to the conduit end, with its jaws adequately open to encircle the circumference.
Is pipe diameter the inside or outside diameter? ›
Pipe was originally used for the movement of water, and therefore the ID (inside diameter) was the critical dimension. The nominal dimension for pipe is the ID. So, 1½ inch pipe is NOT 1½ inch outside diameter, but instead is nominally, (approximately) 1½ inch inside diameter.
What is EMT conduit? ›
Electrical metallic tubing (EMT) is made from coated steel or aluminum and is a more economical and thinner-walled option than other conduit. This conduit type doesn't offer the same protection as rigid metal conduit but is lighter and can be paired with conduit fittings, eliminating the need for threading.
What is the minimum size of conduit commonly used? ›
THE ELECTRICAL WIRING INSTALLATION SHALL BE DONE IN INTERMEDIATE METAL AND RSC CONDUITS. FLEXIBLE CONDUITS SHALL BE USED WHERE REQUIRED. MINIMUM SIZE FOR CONDUITS SHALL BE 13MM DIAMETER TRADE SIZE.
Standard sizing includes 20mm, 25mm, 32mm, 40mm, 50mm, 63mm, 80mm, 100mm, 125mm, 150mm, 200mm in 4m lengths.
What are the actual sizes of EMT? ›
Electrical Metallic Tubing (EMT) - Thinwall Conduit
| Conduit Trade Size | Outside Diameter |
|---|
| (in) | (mm) | (mm) |
|---|
| 1/2 | 16 | 17.9 |
| 3/4 | 21 | 23.4 |
| 1 | 27 | 29.5 |
9 more rowsIn the 2023 NEC, Section 358.10(A)(1) was revised to specifically allow EMT in direct burial applications with fittings identified for direct burial. Code Change Summary: The permitted use of Electrical Metallic Tubing (EMT) has been revised.
What is minimum size EMT? ›
EMT smaller than metric designator 16 (trade size 1/2) shall not be used.
What is the diameter of metal conduits available commercially? ›
There are steel conduit sizes ranging from 38mm to 50mm for larger conduits. Other steel conduit sizes on the market include 1 ½” and 2” diameter conduits. The steel conduit sizes offer a wide range of applications to protect your wiring.
What is the outside diameter of rigid conduit? ›
Rigid Steel Conduit (Heavy Wall Conduit)
| Nominal Conduit Size Inches | Nominal Conduit Size mm | Conduit Outside Diameter Inches |
|---|
| 1-1/4" | 32 | 1.660 |
| 1-1/2" | 40 | 1.900 |
| 2" | 50 | 2.375 |
| 2-1/2" | 60 | 2.875 |
9 more rowsConduit size refers to the internal diameter of the conduit, which dictates the maximum number of wires or cables that can be securely installed within it.
Is flexible conduit measured by ID or OD? ›
OD is the maximum of flexible conduit, and is a fixed number that can not be deviated from. Flexible conduit are always corrugated inner and outer, so we'd better leave more space inner to make wires and cables easier to through. So we should leave 20% space based on inner diameter.
