Menu
Home›Costs›RSJ beam
UK cost guide

RSJ Beam Cost UK

UK RSJ steel beam supply and installation costs for openings, extensions and load-bearing wall work.

Last reviewed: 1 September 2026 · Sources & data · Methodology

Typical planning cost£200–£950 beam + £300–£750 installation
Broader project rangeAbout £500–£1,700 before engineer and making-good costs
Planning figures are estimates rather than quotations. Live calculators combine dated UK benchmarks with clearly separated modelling assumptions such as region, size, condition and specification.

Calculate this project

What affects the cost?

RSJ cost depends on beam length, section weight, access and installation complexity. Structural calculations and building regulations approval are separate requirements for load-bearing structural work.

  • Beam length
  • Section weight
  • Access and lifting
  • Load-bearing wall removal
  • Structural engineer calculations
  • Making good and building control

Typical cost breakdown

RSJ beam, 1–5m£200–£950
Installation, 1–5m£300–£750
Steel benchmark£2.50–£4.50 / kg
Typical engineer RSJ calculationAround £200
Skip / services / making goodUsually additional

Regional planning examples

The examples below apply our published modelling factor to the same national benchmark. They are not claimed as observed city-wide average quotes.

London£640–£2,200
Manchester£470–£1,600
Birmingham£490–£1,650
Glasgow£480–£1,600
Cardiff£460–£1,550

Sources used for this guide

Checkatrade

RSJ Cost Guide 2026: How Much Does an RSJ Beam Cost?

Published / checked: Updated August 2026

Used for: RSJ beam supply, installation and steel cost benchmarks

View source ↗

Frequently asked questions

How much does an RSJ cost installed?

Current UK guidance puts the beam around £200–£950 and installation around £300–£750 for common 1–5m beams, before structural engineering and ancillary work.

Do I need a structural engineer for an RSJ?

For load-bearing structural work you normally need appropriate structural calculations and building regulations approval.

Related costs

Cost guide

House extension

Current UK house extension costs per square metre, with worked size benchmarks, major cost drivers and regional planning context.

£1,800–£3,000 / m²View guide →Cost guide

Build a house

UK new-build and self-build costs per square metre, by house size, specification and project complexity.

£1,400–£3,000 per m²View guide →Cost guide

Builder day rate

Current UK builder day and hourly rate benchmarks for 2026, including self-employed and experienced-builder planning rates.

Around £400 / dayView guide →