Square Steel Tubes (SHS)
Cold-formed and hot-finished square hollow sections from 20×20 mm to 200×200 mm — manufactured in Dammam to EN 10219, EN 10210 and ASTM A500 for construction, fabrication and infrastructure.
Standards
EN 10219EN 10210 · ASTM A500 · BS 4848
Section
20×20 – 200×200mm square (custom on request)
Finish
Black / GalvMill, pre-galv, hot-dip, primed
Lead time
1–2 weeksStock items · custom 3–6 wks
What are square hollow sections?
A square tube — or square hollow section (SHS) — is a closed structural profile with four equal sides and a uniform wall. Its symmetrical box shape gives equal strength and stiffness about both axes, making it one of the most efficient sections for columns, frames and load-bearing fabrication.
Rouad Steel produces square tube on dedicated ERW forming lines: steel strip is cold-roll-formed into a tube, high-frequency welded along the seam, then shaped through a sizing stand into a precise square profile. Hot-finished sections (EN 10210) are also available where tighter corner radii and relieved stresses are specified.
Mill test certificates (EN 10204 3.1) are issued with every batch, covering chemical composition, mechanical properties and dimensional tolerances.
Why engineers choose square tube
A box section that combines structural efficiency with a clean, fabrication-friendly profile.
Equal bi-axial strength
The symmetrical section resists bending and buckling equally in both directions — ideal for columns and posts.
High strength-to-weight
A hollow box places material where it works hardest, giving stiff, lightweight frames and lower steel cost.
Easy to fabricate
Flat faces simplify welding, bolting and flush connections — and make square tube quick to clad and finish.
Clean architectural look
Sharp, uniform faces suit exposed steelwork, railings, furniture and façades with minimal finishing.
Corrosion options
Pre-galvanized, hot-dip galvanized and primed finishes extend service life in exposed environments.
Predictable tolerances
Tight dimensional control on side length, squareness and straightness for repeatable fit-up on site.
Cold-formed, hot-finished & pre-galvanized
Cold-formed (EN 10219)
Roll-formed and ERW-welded at ambient temperature. The most economical, widely-used SHS for general structural and fabrication work.
- Grades S235JRH / S355J2H
- Sharp, consistent corners
- Best value for volume orders
Hot-finished (EN 10210)
Formed and normalized at elevated temperature for relieved residual stress and uniform properties — preferred for heavy or dynamically loaded structures.
- Superior toughness & fatigue
- Tighter corner radii
- Ideal for seismic / cyclic loads
Pre-galvanized
Formed from zinc-coated strip for ready corrosion resistance, or hot-dip galvanized after fabrication for the heaviest-duty exposure.
- Pre-galv & hot-dip options
- Outdoor & humid environments
- Lower lifecycle maintenance
Square tube sizes & weights
Nominal mass per metre for carbon-steel SHS to EN 10219. Other sizes, walls and grades available — ask our team.
→ scroll table| Section (A × A) | Wall t (mm) | Mass (kg/m) | Standard length |
|---|---|---|---|
| 20 × 20 mm | 1.6 | 0.90 | 6 m / cut-to-length |
| 20 × 20 mm | 2.0 | 1.11 | — |
| 20 × 20 mm | 2.5 | 1.36 | — |
| 25 × 25 mm | 2.0 | 1.42 | 6 m / cut-to-length |
| 25 × 25 mm | 2.5 | 1.74 | — |
| 25 × 25 mm | 3.0 | 2.04 | — |
| 30 × 30 mm | 2.0 | 1.74 | 6 m / cut-to-length |
| 30 × 30 mm | 2.5 | 2.14 | — |
| 30 × 30 mm | 3.0 | 2.51 | — |
| 40 × 40 mm | 2.0 | 2.37 | 6 m / cut-to-length |
| 40 × 40 mm | 2.5 | 2.92 | — |
| 40 × 40 mm | 3.0 | 3.45 | — |
| 40 × 40 mm | 4.0 | 4.46 | — |
| 50 × 50 mm | 2.5 | 3.71 | 6 m / cut-to-length |
| 50 × 50 mm | 3.0 | 4.39 | — |
| 50 × 50 mm | 4.0 | 5.72 | — |
| 50 × 50 mm | 5.0 | 6.97 | — |
| 60 × 60 mm | 3.0 | 5.34 | 6 m / cut-to-length |
| 60 × 60 mm | 4.0 | 6.97 | — |
| 60 × 60 mm | 5.0 | 8.54 | — |
| 60 × 60 mm | 6.0 | 10.0 | — |
| 80 × 80 mm | 3.0 | 7.22 | 6 m / cut-to-length |
| 80 × 80 mm | 4.0 | 9.48 | — |
| 80 × 80 mm | 5.0 | 11.7 | — |
| 80 × 80 mm | 6.0 | 13.8 | — |
| 80 × 80 mm | 8.0 | 17.8 | — |
| 100 × 100 mm | 4.0 | 11.9 | 6 m / cut-to-length |
| 100 × 100 mm | 5.0 | 14.8 | — |
| 100 × 100 mm | 6.0 | 17.5 | — |
| 100 × 100 mm | 8.0 | 22.6 | — |
| 100 × 100 mm | 10.0 | 27.4 | — |
| 120 × 120 mm | 5.0 | 17.9 | 6 m / cut-to-length |
| 120 × 120 mm | 6.0 | 21.2 | — |
| 120 × 120 mm | 8.0 | 27.6 | — |
| 120 × 120 mm | 10.0 | 33.7 | — |
| 150 × 150 mm | 5.0 | 22.6 | 6 m / cut-to-length |
| 150 × 150 mm | 6.0 | 26.8 | — |
| 150 × 150 mm | 8.0 | 35.1 | — |
| 150 × 150 mm | 10.0 | 43.1 | — |
| 150 × 150 mm | 12.0 | 50.7 | — |
| 200 × 200 mm | 6.0 | 36.2 | 6 m / cut-to-length |
| 200 × 200 mm | 8.0 | 47.7 | — |
| 200 × 200 mm | 10.0 | 58.8 | — |
| 200 × 200 mm | 12.0 | 69.6 | — |
Weights are indicative and rounded. Tolerances on mass, dimensions and straightness are per the relevant standard. Need a stock list or a section not shown here? Contact our sales desk.
Where square tube is used
From heavy structural frames to architectural metalwork, square tube is one of the most versatile sections in steel.
- Building columns & frames
- Steel trusses & portal frames
- Mezzanines & platforms
- Carports, canopies & sheds
- Fencing, gates & railings
- Handrails & balustrades
- Furniture & shelving frames
- Signage & lighting posts
- Agricultural & greenhouse structures
- Trailer & chassis fabrication
- Solar mounting structures
- Machine guards & enclosures
Need square tube for a project?
Send us your cutting list or BOQ — we reply with pricing, weights and mill test certificates within 24 hours.
Specifications we manufacture to
| Standard | Type | Common grades | Notes |
|---|---|---|---|
| EN 10219 | Cold-formed welded | S235JRH, S355J2H | General structural SHS |
| EN 10210 | Hot-finished welded | S275J2H, S355J2H | Heavy / dynamic loads |
| ASTM A500 | Cold-formed welded | Gr B, Gr C | US structural tubing |
| BS 4848-2 | Hot-finished | S275, S355 | Legacy UK projects |
| ASTM A53 / A1085 | Welded | Gr B | On request |