Metal Fencing: Tubular Construction Vs Solid Steel
Metal fencing comes in many forms, but one of the most important distinctions lies in the type of steel used in its construction. Two of the most common approaches are tubular steel and solid steel. Although solid steel may sound stronger at first, tubular construction often delivers far superior strength, durability, and performance. This applies across security fencing, metal railings, gates, and posts.
This article explains why tubular and square tube steel consistently outperform flat bar and rolled steel, and how these engineering advantages are used in modern metal fence design.
Why tubular steel is stronger than flat bar or rolled steel
The strength of steel does not depend only on the material itself. The shape of the section plays a major role. Tubular steel and square hollow sections offer significant structural advantages compared with flat bar, strip, or hot or cold rolled shapes.
Better load distribution
A hollow tube places the material around the perimeter. This creates a higher second moment of area, which means the section resists bending much more effectively than a solid strip of the same weight. In simple terms, a hollow tube behaves like a miniature I beam, using geometry to increase strength.
Greater rigidity with less weight
A tubular section can be lighter than solid steel while still resisting twist and flex. A flat bar will deform more easily because it lacks depth. The same applies to angles, which are usually shaped like an L in cross section. Although angles are common in low duty fabrications, they are not ideal where strength and impact resistance are required.
Higher resistance to impacts
Tubular sections absorb and distribute force more effectively. A flat bar, round bar, or rolled angle will tend to deflect or buckle when hit. Tubular construction spreads the energy across the whole circumference, keeping the fence intact under pressure.
Tubular rails versus hot rolled or cold rolled steel angles
In metal fencing, the horizontal rails play a major structural role. They carry the pales and transfer loads into the posts.
A rail made from tubular steel is much stronger than a rail made from hot rolled or cold rolled angles. An angle is essentially a thin L shape that can twist or open when force is applied. A tube has equal strength in every direction and resists both bending and torsion. This is especially important where the fence must withstand climbing attempts, ball games, livestock pressure, or repeated impacts.
Tubular rails also allow a more advanced method of assembly. Pales can pass through the rail rather than being attached with external fixings. This through rail construction locks each pale in place and creates a single unified structure. It removes weak points such as bolts and clips, and also produces a much cleaner finish.
Tubular pales versus flat pales
The same engineering principles apply to the vertical pales. A flat pale is simply a narrow strip of steel and has very little resistance to bending. It can be twisted or bent by hand and offers limited security value.
A tubular pale, whether circular, square, or elliptical, has dramatically more strength. It withstands bending, does not deform easily, and remains rigid even under significant force. This makes tubular pales ideal for security fencing, sports ground perimeters, anti climb systems, and high impact environments.
A useful comparison is found in railing design. A hairpin railing that uses solid steel bar pales is noticeably weaker than a railing built with tubular pales. Although the solid bars contain more metal, the lack of depth means they bend along their length like a piece of wire. A tubular pale of the same width stays straight and resists deformation.
Read our blog on triple point palisade and the downfalls of it not being manufactured from tubular material
Tubular construction in metal railings
Traditional metal railings often used round or square solid bar. While this gives a heavy appearance, it is not the most robust choice. Modern railing systems use tubular pales and tubular rails to create a fence that is both stronger and more economical.
For example
- Bow top railings are more resilient when the curved top is formed from tubular steel.
- Vertical bar railings withstand crowd pressure and impacts more effectively when the bars are hollow sections rather than solid bar.
- Decorative railings benefit from the same increased rigidity, allowing thinner looking designs without compromising strength.
Tubular posts for maximum structural integrity
The fence posts are the main load bearing components. Using tubular or square hollow section posts gives the fence a rigid foundation. A flat bar or rolled angle post would twist under load, and even a solid bar post would not offer the same level of structural stability due to its reduced resistance to bending.
Tubular posts resist both lateral loads and vertical loads. They remain stable in high wind zones, on uneven ground, and when supporting heavy gates. This is why modern security fences and railings use hollow section posts as standard.
When tubular construction is essential
Tubular steel is the preferred choice for any metal fence designed for security, safety, or long term durability. Examples include
- School and sports ground fencing
- Security mesh panel systems
- Vertical bar railings
- Tubular railings for public spaces
- Play area railings
- Commercial and industrial perimeters
- Gates and automated access systems
In almost every case, a tubular version of a component will be stronger than a solid or flat equivalent. The engineering benefits are clear, and this is why tubular construction has become the benchmark for modern metal fencing.
