When you’re planning a house renovation, extension or structural alteration, one vital question arises: how much will a structural engineer cost you? Whether it’s a report for a home extension, structural drawings for load-bearing wall removal, or full calculations for a basement or loft conversion, knowing the ball-park figures and what drives them can help you budget wisely.

Key Services – Reports, Calculations, Surveys, Structural Drawings

A structural engineer inspects, assesses and designs the structural elements of your project. This might include producing a structural report (identifying defects or issues + recommendations), preparing calculations and drawings for structural work (such as removing a load-bearing wall or installing an RSJ), or validating foundations, retaining walls or conversions. For example: small-scale work like a lintel replacement, or large-scale work like a basement excavation.

Typical Project Types – Load Wall Removal, Extensions, Loft/Basement, Retaining Walls

Common jobs include:

• Removal of a load-bearing wall + RSJ installation

• Single or double storey home extensions needing calculations

• Loft or basement conversions requiring full structural design

• Retaining wall or underpinning works where ground forces are significant

Typical Cost Ranges for Common Jobs

Here are typical UK cost ranges (2025) based on various guides:

• Hourly rate: ~ £90-£200 for straightforward engineered services.

• Basic structural report (home renovation): ~ £350-£450.

• Medium job (extension/loft conversion): £500-£2,000+.

• Larger/complex work: £2,000-£10,000+ depending on scope.

Cost Table – Small Projects, Medium Projects, Large/Complex Projects

Example Costs for London/Surrey vs UK Average

Because property values and labour rates are higher in London and the South-East, you should budget 20-30% above the UK average. When quoting for London/Surrey homes, structural engineers may charge a premium, especially for drawings/site visits in congested areas.

Project Complexity & Scope

The more structural change (foundation work, large span beams, new build vs renovation) the higher the cost. Complex ground conditions, listed buildings or structural defects require more time and expertise.

Location & Property Type (London/Surrey Premium)

As above, projects in the London/Surrey area cost more due to higher overheads, travel, higher insurance, and regulatory complexity.

Engineer Experience & Deliverables (Report, Drawings, Site Visit)

A senior engineer, full drawings + calculations + detailed report = higher fee than a simple site review. Ensure your quote differentiates “report only” vs “full package”.

Required by Building Regulations or When Structural Work Is Involved

If your project involves load-bearing walls, major structural alterations, new builds, or building regulation submission, you’ll almost always need a structural engineer. Many UK guides emphasise this. 

Projects Where It Might Be Optional – But Still Wise

For simpler non-structural changes (e.g., cosmetic refurbishment, non-load bearing partition removal) you may not legally need an engineer, but hiring one still mitigates risk and supports compliance.

What Should Your Quote Include?

A reliable quote should list: engineer’s scope (site visit, designs, report), deliverables (drawings, calculations), fees for revisions/site inspections, travel costs, VAT, timeline.

Questions to Ask Your Structural Engineer

• Is the fee fixed or based on hours?

• Will the quote include structural drawings and building regulation submission if needed?

• Are additional site inspections included?

• What are the payment milestones?

Ways to Control Costs Without Compromising Safety

• Provide clear brief and information to engineer to reduce revisions

• Use local engineers (reduces travel/time)

• Bundle drawings with other consultants (architect + engineer) for economies

• Avoid late design changes which increase cost substantially

Our Local UK Experience (London & Surrey)

With years of experience delivering home renovations, extensions and structural work across London & Surrey, KT5 Construction brings local insight and relationships with structural engineers and building control teams.

Full Project Support – From Consultation to Drawings to Build

We don’t just manage the build: our team coordinates structural engineer appointment, drawings, building regs submission and the build itself — reducing duplication and cost inefficiencies.

Transparent Pricing, Budgeting & Deliverables

Our quotes include detailed breakdowns of structural-engineering fees, so you understand what you’re paying. We help you compare costs and manage your budget effectively.

Project-First Approach & Compliance

We prioritise quality, safety and compliance — whether it’s removing a load-bearing wall, designing an extension or managing structural defects — your home remains safe, compliant and future-sale proof.