RSJ Size and Specification UK

Expert Steel Beam Size Guide - RSJ Steel Beams in Hampshire, Surrey, and London

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RSJ Steel Beam Sizes and Specifications

  • 127 x 76 x 13 Mild Steel Universal Beam RSJ
  • 152 x 89 x 16 Mild Steel Universal Beam RSJ
  • 152 x 152 x 23 Mild Steel Universal Beam RSJ
  • 152 x 152 x 30 Mild Steel Universal Beam RSJ
  • 152 x 152 x 37 Mild Steel Universal Beam RSJ
  • 178 x 102 x 19 Mild Steel Universal Beam RSJ
  • 203 x 102 x 23 Mild Steel Universal Beam RSJ
  • 203 x 133 x 25 Mild Steel Universal Beam RSJ
  • 203 x 133 x 30 Mild Steel Universal Beam RSJ
  • 203 x 203 x 46 Mild Steel Universal Beam RSJ
  • 203 x 203 x 52 Mild Steel Universal Beam RSJ
  • 203 x 203 x 60 Mild Steel Universal Beam RSJ
These RSJ beams are made from high-quality mild steel, ensuring exceptional durability, strength, and resistance to corrosion. They are suitable for a wide range of applications, including residential, commercial, and industrial construction projects.
These are larger sizes of RSJ Steel Beams available:

For construction projects that require superior load-bearing capacity and structural integrity, Home Build Extensions offers a range of larger RSJ steel beam sizes:

  • 356 x 127 x 39 Mild Steel Universal Beam RSJ
  • 356 x 171 x 45 Mild Steel Universal Beam RSJ
  • 356 x 171 x 51 Mild Steel Universal Beam RSJ
  • 356 x 171 x 57 Mild Steel Universal Beam RSJ
  • 356 x 171 x 67 Mild Steel Universal Beam RSJ
  • 406 x 140 x 39 Mild Steel Universal Beam RSJ
  • 406 x 140 x 46 Mild Steel Universal Beam RSJ
  • 406 x 178 x 54 Mild Steel Universal Beam RSJ
  • 406 x 178 x 60 Mild Steel Universal Beam RSJ
  • 406 x 178 x 67 Mild Steel Universal Beam RSJ
  • 406 x 178 x 74 Mild Steel Universal Beam RSJ
  • 457 x 152 x 52 Mild Steel Universal Beam RSJ
  • 457 x 152 x 60 Mild Steel Universal Beam RSJ
  • 457 x 152 x 67 Mild Steel Universal Beam RSJ
  • 457 x 152 x 74 Mild Steel Universal Beam RSJ
  • 457 x 152 x 82 Mild Steel Universal Beam RSJ
  • 457 x 191 x 67 Mild Steel Universal Beam RSJ
  • 457 x 191 x 74 Mild Steel Universal Beam RSJ
  • 457 x 191 x 82 Mild Steel Universal Beam RSJ
  • 457 x 191 x 89 Mild Steel Universal Beam RSJ
  • 457 x 191 x 98 Mild Steel Universal Beam RSJ

These larger RSJ steel beams are designed to provide exceptional strength and durability for heavy-duty construction projects, such as industrial buildings, bridges, and large-scale structures.

They are manufactured from high-quality mild steel, ensuring superior corrosion resistance, weldability, and machinability.

Applications and Benefits of RSJ Steel Beams

RSJ steel beams are widely used in various construction projects due to their versatility and strength.

They are commonly employed as lintels, support beams, and load-bearing structures in buildings, bridges, and other infrastructure projects.

Some of the key benefits of using RSJ steel beams include:

  • High load-bearing capacity
  • Excellent structural integrity
  • Resistance to deformation and deflection
  • Long-lasting durability
  • Easy installation and fabrication
  • Cost-effectiveness

At Home Build Extensions, we understand the importance of quality and reliability in construction projects.

Our RSJ steel beams are sourced from reputable suppliers and undergo rigorous quality checks to ensure they meet the highest industry standards.

Side Return House Extension glazing above new extension roofing install.

What Is an RSJ / Steel Beam?

An RSJ (Rolled Steel Joist) , also known as an “I” beam, is a steel girder or lintel used to support structures during building house extensions or home renovations. It provides strength and stability by distributing weight uniformly.

Builders in Camberley - House Extension on a property in Surrey.

How Much Does RSJ Supply and Installation Cost?

The cost varies based on factors such as beam size, property type, location, and additional services. Typically, RSJ installation costs between £1,500 and £2,500, including: Hiring a structural engineer Plastering Skip hire Building control approval fees Materials and labour.

What is the difference between 254 x 102 x 22 and 254 x 102 x 25 RSJ beams?
The difference between these two RSJ beam sizes lies in their weight and load-bearing capacity. The 254 x 102 x 25 beam has a larger cross-sectional area, making it heavier and capable of supporting greater loads compared to the 254 x 102 x 22 beam.
How does the price of RSJ beams vary with different dimensions?
The price of RSJ beams is directly proportional to their size and weight. Larger and heavier beams with greater cross-sectional areas generally cost more than smaller and lighter beams. This is because they require more raw material and have higher manufacturing costs.
Are there any additional costs for delivery of RSJ beams?
Yes, there may be additional costs for the delivery of RSJ beams, depending on the distance, weight, and quantity of the beams being shipped. Delivery charges are typically calculated based on the total weight and distance of the shipment.
What are the common applications for 254 x 102 x 28 RSJ beams?
The 254 x 102 x 28 RSJ beams are commonly used in residential and commercial construction projects as load-bearing beams, lintels, and support structures. They are suitable for applications such as building extensions, mezzanine floors, and structural reinforcements.
Can I get a quote for a custom length of RSJ beam?
Absolutely! At Home Build Extensions, we understand that construction projects often require custom lengths of RSJ beams. Our team will be happy to provide you with a quote for a custom length based on your specific requirements.

Some of our recent Steel Projects in Hampshire / Surrey

Explore Our Steel Supply and Installation Portfolio: Immerse yourself in inspiration with our gallery of completed projects in Hampshire, Surrey and London.

Trusted Steel Beam experts for Award-Winning Builders in the UK

Does your Hampshire or Surrey home feel cramped or outdated? We can help! At Home Build Extensions, our passionate Steel Installation experts specialise in crafting dream spaces tailored to your unique vision with their steel structured buildings and extensions.

More Than Just Steel, We Create:

Our award-winning RSJ Installers in Hampshire are renowned for:

  • Seamless Home Extensions: We don’t just add square footage we pur steel; we create beautiful extensions with our steel install projects throughout Hampshire and Surrey.
  • Transformative Renovations: Breathe new life into your current space! From kitchens and bathrooms to complete makeovers, with a Wall Removal and Steel above to take space to another level. We excel at renovations that enhance functionality and style.
  • Award-Winning Landscaping Design: Envision a captivating outdoor haven that seamlessly integrates with your home. Our RSJ Steel installation team will transform your vision into a stunning reality.
Top Builders in Camberley creating a Home Extension for a house in Camberley, Surrey.
Modern Home Extension with new kitchen installed in Surrey
House Extension with Bi Fold Doors in the UK.
Modern house conversion for a home extension project.
Home renovation concept. Before and after interior in modern style. Living room
The Visofold Heritage Bi-Fold Doors are a great fit for any conservatory, modern or classic theme homes.
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Your Trusted Steel experts in Hampshire, Surrey and London

Steel Beam installation experts in the UK

Award-Winning Expertise: Our Steel Install team covering Hampshire, Surrey and London are recognised for their exceptional craftsmanship and commitment to excellence.

Unleash the Strength of Your Home Project with Expert RSJ Steel Beam Installation

Strength and Efficiency:

  • Superior Load Bearing: Steel boasts an incredible strength-to-weight ratio. This translates to beams that can handle immense loads without requiring excessive material. This allows for expansive layouts, grand designs, and the ability to create large open spaces, all without compromising structural integrity.

Diverse Projects:

  • Adaptability: Steel beams come in a vast array of sizes and lengths. This caters to a wide range of projects, from domestic extensions and renovations to large-scale commercial and industrial buildings.
  • Architectural Freedom: Unlike some traditional materials, steel beams don’t restrict design possibilities. They can be incorporated into various architectural styles, enabling the creation of open floor plans, stunning vaulted ceilings, and other creative features.


  • Built to Last: Steel is naturally resistant to fire, rot, insect infestation, and harsh weather conditions. This ensures the longevity and structural stability of your building for decades to come. Minimal maintenance is required, further reducing lifecycle costs.

Speed and Efficiency:

  • Faster Construction: Steel beams are pre-fabricated off-site, allowing for quicker installation compared to traditional methods like brickwork. This translates to faster project completion times and reduced overall construction costs.
  • Lightweight Advantage: The lighter weight of steel beams compared to concrete or masonry translates to easier transportation, handling, and installation. This minimizes disruption on the construction site and reduces the need for heavy machinery.

Eco-Conscious Builder:

  • Recyclable Material: Steel is one of the most recyclable construction materials available. A significant portion of steel used today comes from recycled sources, minimizing environmental impact.
  • Reduced Construction Waste: The pre-fabrication process for steel beams minimizes on-site waste compared to traditional construction methods.

UK Building Regulations:

  • Code Compliance: Steel is a well-documented and extensively tested material. Steel beams are manufactured to meet stringent UK building regulations, ensuring the safety and structural integrity of your building.

In conclusion, steel beams offer a compelling combination of strength, versatility, durability, efficiency, and sustainability. These factors make them an essential choice for construction projects of all shapes and sizes across the UK. From the bustling cityscapes to charming villages, steel beams are the backbone of modern British construction.

Contact us about your RSJ Steel Beam Project in Hampshire, Surrey or London

Looking to expand your living space or build strong in Hampshire, Surrey, or London? Home Build Extensions, located in Hampshire (tel: 07754 271410 | email:, is your one-stop shop for top-quality steel beam supply and installation.

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