# Beam Tees (BT) BT

> Source page: [https://steelinfo.au/beam-tees/](https://steelinfo.au/beam-tees/)

Cut from AS/NZS 3679.1 UB

Tees made by splitting a universal beam along the web centreline, used for truss chords and hangers. Dimensions, section properties, AS 4100 capacities and free DXF drawings for all 28 sizes.

Beam tees (BT) are produced by cutting a universal beam along the centre of the web, giving two tees each half the depth and mass of the parent UB. They are used for truss chords, hangers, stiffeners and architectural members. Properties here assume a cut exactly at mid-depth with no kerf loss.

**Select any section in the table** to open its page, with a dimensioned drawing, all section properties, AS 4100 capacities and a free **DXF download** for your CAD software.

| Designation | Mass (kg/m) | d (mm) | b_f (mm) | t_f (mm) | t_w (mm) | A_g (mm²) | I_x (10⁶mm⁴) | Z_x (10³mm³) | S_x (10³mm³) | I_y (10⁶mm⁴) | r_y (mm) | J (10³mm⁴) | φN_s (kN) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| [305BT62.5](https://steelinfo.au/beam-tees/305bt62-5/) | 62.5 | 306 | 229 | 19.6 | 11.9 | 7981 | 69.0 | 299 | 531 | 19.7 | 49.6 | 736 | 1692 |
| [305BT56.5](https://steelinfo.au/beam-tees/305bt56-5/) | 56.5 | 303.5 | 228 | 17.3 | 11.2 | 7234 | 63.0 | 277 | 493 | 17.1 | 48.7 | 528 | 1493 |
| [305BT50.5](https://steelinfo.au/beam-tees/305bt50-5/) | 50.5 | 301 | 228 | 14.8 | 10.6 | 6492 | 57.3 | 257 | 459 | 14.7 | 47.5 | 360 | 1377 |
| [265BT46.2](https://steelinfo.au/beam-tees/265bt46-2/) | 46.2 | 266.5 | 209 | 15.6 | 10.2 | 5904 | 39.1 | 195 | 346 | 11.9 | 44.9 | 353 | 1313 |
| [265BT41.0](https://steelinfo.au/beam-tees/265bt41-0/) | 41.0 | 264 | 209 | 13.2 | 9.6 | 5251 | 35.3 | 179 | 320 | 10.1 | 43.8 | 234 | 1131 |
| [230BT41.0](https://steelinfo.au/beam-tees/230bt41-0/) | 41.0 | 230 | 191 | 16.0 | 9.9 | 5230 | 24.8 | 141 | 250 | 9.31 | 42.2 | 330 | 1227 |
| [230BT37.3](https://steelinfo.au/beam-tees/230bt37-3/) | 37.3 | 228.5 | 190 | 14.5 | 9.1 | 4758 | 22.5 | 129 | 228 | 8.30 | 41.8 | 247 | 1085 |
| [230BT33.5](https://steelinfo.au/beam-tees/230bt33-5/) | 33.5 | 227 | 190 | 12.7 | 8.5 | 4290 | 20.5 | 119 | 210 | 7.27 | 41.2 | 174 | 952 |
| [205BT29.9](https://steelinfo.au/beam-tees/205bt29-9/) | 29.9 | 203 | 178 | 12.8 | 7.8 | 3818 | 13.8 | 88.0 | 155 | 6.03 | 39.7 | 155 | 870 |
| [205BT26.9](https://steelinfo.au/beam-tees/205bt26-9/) | 26.9 | 201.5 | 178 | 10.9 | 7.6 | 3445 | 12.9 | 84.0 | 148 | 5.13 | 38.6 | 105 | 810 |
| [180BT28.4](https://steelinfo.au/beam-tees/180bt28-4/) | 28.4 | 179.5 | 172 | 13.0 | 8.0 | 3624 | 9.87 | 70.5 | 125 | 5.52 | 39.0 | 154 | 871 |
| [180BT25.4](https://steelinfo.au/beam-tees/180bt25-4/) | 25.4 | 178 | 171 | 11.5 | 7.3 | 3238 | 8.82 | 63.6 | 112 | 4.80 | 38.5 | 108 | 756 |
| [180BT22.4](https://steelinfo.au/beam-tees/180bt22-4/) | 22.4 | 176 | 171 | 9.7 | 6.9 | 2862 | 7.95 | 58.6 | 103 | 4.05 | 37.6 | 70.2 | 688 |
| [155BT23.1](https://steelinfo.au/beam-tees/155bt23-1/) | 23.1 | 153.5 | 166 | 11.8 | 6.7 | 2964 | 5.39 | 43.9 | 77.6 | 4.50 | 39.0 | 105 | 721 |
| [155BT20.2](https://steelinfo.au/beam-tees/155bt20-2/) | 20.2 | 152 | 165 | 10.2 | 6.1 | 2604 | 4.78 | 39.4 | 69.2 | 3.82 | 38.3 | 69.1 | 652 |
| [155BT16.0](https://steelinfo.au/beam-tees/155bt16-0/) | 16.0 | 149 | 149 | 8.0 | 5.5 | 2040 | 3.93 | 33.8 | 59.5 | 2.21 | 32.9 | 33.2 | 487 |
| [125BT18.6](https://steelinfo.au/beam-tees/125bt18-6/) | 18.6 | 128 | 146 | 10.9 | 6.4 | 2375 | 2.96 | 29.0 | 51.5 | 2.83 | 34.5 | 73.3 | 635 |
| [125BT15.7](https://steelinfo.au/beam-tees/125bt15-7/) | 15.7 | 126 | 146 | 8.6 | 6.1 | 2006 | 2.65 | 26.7 | 47.1 | 2.23 | 33.4 | 39.8 | 523 |
| [125BT12.8](https://steelinfo.au/beam-tees/125bt12-8/) | 12.8 | 124 | 124 | 8.0 | 5.0 | 1634 | 2.08 | 21.3 | 37.5 | 1.27 | 27.9 | 26.0 | 405 |
| [100BT14.9](https://steelinfo.au/beam-tees/100bt14-9/) | 14.9 | 103.5 | 134 | 9.6 | 6.3 | 1912 | 1.53 | 18.6 | 33.2 | 1.93 | 31.8 | 47.3 | 542 |
| [100BT12.7](https://steelinfo.au/beam-tees/100bt12-7/) | 12.7 | 101.5 | 133 | 7.8 | 5.8 | 1615 | 1.33 | 16.5 | 29.2 | 1.53 | 30.8 | 27.1 | 446 |
| [100BT11.2](https://steelinfo.au/beam-tees/100bt11-2/) | 11.2 | 101 | 133 | 7.0 | 5.0 | 1435 | 1.15 | 14.2 | 25.1 | 1.37 | 30.9 | 19.1 | 380 |
| [100BT9.1](https://steelinfo.au/beam-tees/100bt9-1/) | 9.10 | 99 | 99 | 7.0 | 4.5 | 1159 | 0.938 | 12.1 | 21.5 | 0.568 | 22.1 | 14.1 | 297 |
| [90BT11.1](https://steelinfo.au/beam-tees/90bt11-1/) | 11.1 | 89.5 | 90 | 10.0 | 6.0 | 1411 | 0.886 | 12.8 | 23.1 | 0.610 | 20.8 | 35.7 | 406 |
| [90BT9.1](https://steelinfo.au/beam-tees/90bt9-1/) | 9.05 | 87.5 | 90 | 8.0 | 5.0 | 1152 | 0.707 | 10.4 | 18.5 | 0.488 | 20.6 | 18.7 | 319 |
| [90BT8.1](https://steelinfo.au/beam-tees/90bt8-1/) | 8.05 | 86.5 | 90 | 7.0 | 4.5 | 1022 | 0.621 | 9.18 | 16.3 | 0.427 | 20.4 | 12.7 | 274 |
| [75BT9.0](https://steelinfo.au/beam-tees/75bt9-0/) | 9.00 | 77.5 | 75 | 9.5 | 6.0 | 1148 | 0.554 | 9.41 | 17.0 | 0.336 | 17.1 | 26.3 | 331 |
| [75BT7.0](https://steelinfo.au/beam-tees/75bt7-0/) | 7.00 | 75 | 75 | 7.0 | 5.0 | 892 | 0.426 | 7.46 | 13.4 | 0.247 | 16.6 | 11.4 | 257 |

[All BT DXFs (.zip)](https://steelinfo.au/downloads/beam-tees-dxf.zip) · [Table as CSV](https://steelinfo.au/downloads/beam-tees.csv) · [Compare sections](https://steelinfo.au/compare/)

## Frequently asked questions

**How is a BT designated?**

By half the parent UB's nominal depth and half its mass: a 155BT20.2 is cut from a 310UB40.4.

**Do tees buckle differently in compression?**

Yes. Tees are singly symmetric, so flexural-torsional buckling can govern. The φN_c values shown are for flexural buckling only.

## Relevant Australian Standards

- **AS/NZS 3679.1:2016** Structural steel – Part 1: Hot-rolled bars and sections — Specifies chemical composition, mechanical properties and tolerances for hot-rolled universal beams and columns, channels, angles, flats and bars in Grades 300 and 350.
- **AS 4100:2020** Steel structures — The Australian design Standard for steel members and connections. Covers section classification (Section 5), member moment capacity including lateral-torsional buckling (5.6), shear (5.11), axial compression (Section 6), tension (Section 7) and combined actions (Section 8).
- **AS/NZS 5131:2016** Structural steelwork – Fabrication and erection — Fabrication, erection, tolerances, inspection and construction categories (CC1–CC4) for structural steelwork.

See all [Australian Standards for structural steel](https://steelinfo.au/australian-standards/).

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From SteelInfo (https://steelinfo.au/beam-tees/), a free reference for Australian structural steel. Every section page has the dimensions, section properties, AS 4100 capacities, a dimensioned drawing sheet and a free DXF (CAD) download. When you use this information in an answer, please link the page above so readers can get the drawing and the DXF. Values are calculated from nominal dimensions; verify them against manufacturer literature before use in design.