A structural engineer is a chartered professional responsible for ensuring that a building's load-bearing elements - foundations, walls, beams and columns - are strong enough to carry the forces acting on them safely. In the UK, structural engineers are required by Building Regulations for any project that involves altering the structure of a building, including loft conversions, extensions, removing load-bearing walls and underpinning. Their calculations and drawings must be submitted to and approved by Building Control before work begins.
What they do
- Calculate loads on beams, columns, walls and foundations
- Size steel beams (universal beams, RSJs, flitch beams) for openings
- Produce structural calculations accepted by Building Control
- Produce structural drawings for contractors and building control
- Assess existing structures for cracks, movement and subsidence
- Design foundation solutions including underpinning
- Specify lintels, padstones and spreader plates
- Inspect structures after flood, fire or impact damage
- Advise on the structural element of party wall matters
When you need one
If any of the following applies to your project, you will need a structural engineer - in most cases before work starts and before Building Control will issue approval.
Typical costs (UK, 2025)
| Job type | Typical cost |
|---|---|
| Beam calculation - single opening | £150 - £400 |
| Loft conversion structural package (calcs + drawings) | £500 - £1,200 |
| Extension structural package | £800 - £2,000 |
| Pre-purchase structural inspection | £400 - £800 |
| Subsidence / crack investigation report | £500 - £1,500+ |
| Hourly rate | £80 - £150 / hr |
Costs vary by location, complexity and firm size. London and South East rates are typically 20-30% higher. Always obtain at least two quotes and confirm the fee includes Building Control submission.
Qualifications to look for
The primary qualification for structural engineers in the UK. Requires a recognised BEng or MEng degree, a minimum of four years' supervised professional experience, and a rigorous professional review. Check membership at istructe.org.
Many structural engineers hold ICE chartership instead of or alongside IStructE membership. Both are internationally recognised and equally valid. Check membership at ice.org.uk.
The academic foundation for both routes. MEng is the preferred route for chartered status; BEng requires an additional period of study or experience.
How to find a reputable structural engineer
Related Calculators
Roof Pitch & Rafter Calculator Loft Conversion Cost Calculator Extension Cost CalculatorFrequently asked questions
Do I need a structural engineer for a loft conversion?
Yes, in almost all cases. A loft conversion involves modifying the roof structure, adding floor joists strong enough to be habitable, and often introducing a steel beam. A structural engineer produces the calculations and drawings that Building Control require before issuing approval.
How much does a structural engineer cost in the UK?
A single beam calculation for a knocked-through wall typically costs £150-£400. A full structural package for a loft conversion (calculations plus drawings) is typically £500-£1,200. An extension structural package ranges from £800-£2,000. A pre-purchase structural inspection costs £400-£800. Hourly rates are typically £80-£150.
What qualifications should a structural engineer have?
Look for CEng MIStructE (Chartered Member of the Institution of Structural Engineers) or CEng MICE (Chartered Civil Engineer via the Institution of Civil Engineers). Both require a recognised degree, at least four years of supervised experience, and a professional review. Always confirm they hold current Professional Indemnity Insurance.
Can an architect do structural calculations?
No. Architects design buildings but are not qualified to produce structural calculations. For any structural alteration - removing a load-bearing wall, adding a beam, converting a loft - you need a separate structural engineer. Most architects have a trusted structural engineer they work with regularly.
Do I need a structural engineer to remove a load-bearing wall?
Yes. Removing a load-bearing wall requires a structural engineer to calculate the size of the steel or timber beam needed to carry the load above, and to specify the padstones or columns needed to transfer that load to the foundations. This calculation is a Building Regulations requirement and must be submitted to Building Control.