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What changes the cost of a structural engineer?
A structural engineer's fee depends on what you need: a visit and short report, calculations and drawings for building control, or a full design for an extension or conversion. Site visits, the size of the job and any revisits change the total, so this guide prints no fee and explains what to compare.
Last reviewed:What does a structural engineer do on a home project?
A structural engineer works out how a building carries its weight and whether a change will keep it standing safely. On a home project they usually:
- size a beam to replace a load-bearing wall
- design the structure of an extension, loft conversion or basement
- inspect cracks or movement and say what is causing it
- design repairs, such as new lintels, ties or underpinning
- answer building control's questions about the structure
Most homeowners need an engineer for one specific question, not the whole project. That is good news for the fee, because it can be scoped to that question.
This guide does not print a fee, an hourly rate or a typical total. It explains what changes an engineer's price and what their fee letter should say, so you can compare engineers on the same terms.
QuoteZila starts in Cheshire, with Crewe, Nantwich and Sandbach first, and anyone in the UK can post a job that needs an engineer.
When do you need a structural engineer?
Removing or opening up a load-bearing wall. The Planning Portal says building regulations will normally apply if you remove an internal wall or form an opening in one, and explains that load-bearing walls carry loads from other parts of the structure, roof and floors down to the foundations [S3]. It says care should be taken before removing any internal wall [S3]. On the Planning Portal's Interactive House, it says removing a load-bearing wall in a flat will require building control approval as it alters the structure, and you will be required to provide a report from a structural engineer who will provide structural calculations [S2].
Extensions and large openings. The Federation of Master Builders says that where structural elements are altered, such as removing load-bearing walls or forming large bi-fold door openings, structural calculations are essential [S1].
Chimney breasts. The Interactive House says that if work goes to an internal chimney stack or breasts, building regulations will be needed to understand the structural impact [S2]. Removing a chimney breast explains the job.
Loft conversions and basements. New floors, steel beams, dormers and dug-out floors all need structural design. Cellar conversion and loft conversion cover those projects.
Cracks, bulges and movement. An engineer can tell you whether a crack is settlement, movement that has stopped, or something still happening.
GOV.UK says building regulations approval is different from planning permission, that you might need both, and that you should check with a building control body if you can't decide whether you need approval [S4]. GOV.UK: building regulations approval. QuoteZila is not affiliated with this organisation. GOV.UK explains when you need building regulations approval.
What types of service do engineers offer?
| Service | What you usually get | What changes the fee |
|---|---|---|
| Visual inspection and letter | A visit and a short written opinion | Travel, access, how much there is to see |
| Structural report | A fuller written report on a defect, with photos and advice | Size of the problem, monitoring, research |
| Beam or lintel calculations | Calculations for one beam or opening | Number of beams, loads above, point loads |
| Calculations and drawings | Calculations plus drawings for building control | Number of drawings and details |
| Full structural design | Design for an extension, conversion or basement | Size and complexity of the project |
| Site visits during work | Checking openings, ground or steel on site | Number of visits |
| Building control queries | Answering questions after submission | Time spent, rounds of comments |
A fee letter should say which of these is included. Ask what happens, and what it costs, if building control asks for changes or the builder finds something unexpected.
What changes a structural engineer's fee?
Whether they need to visit. Some calculations can be done from good photos and measurements. Others need the engineer to see the house, especially if the loads above the wall are not clear.
The loads above. A wall carrying only a ceiling is simpler than one carrying a floor, a roof and another wall. Point loads, where a beam rests on another beam or post, add work.
Opening-up. The engineer may need to see what is behind plaster, under floors or in the loft. Who does the opening-up, and who pays, should be clear.
Drawings. Many builders and building control officers want a drawing as well as calculations. Some engineers include simple sketches. Others charge separately for drawings.
Foundations and ground. Extensions and underpinning depend on ground conditions. Trial holes or ground investigation may be needed, and are usually priced separately.
Revisions. If the design changes, or building control raises questions, there may be extra time. Ask how revisions are charged.
Urgency. Ask whether a quicker turnaround costs more.
The Federation of Master Builders says professional and compliance costs can add approximately 15-20% to an extension budget, depending on how complex the project is [S1]. That covers more than the engineer, but it shows why design fees belong in the budget from the start.
Does a party wall affect the engineer's work?
It can. GOV.UK says you must tell your neighbours if you want to carry out building work near or on your shared boundary, or party wall, in England and Wales, and that party walls include walls that form part of a building and garden walls, but not wooden fences [S5]. It says party wall agreements are different from planning permission and building regulations approval [S5].
If a beam will sit in a party wall, or an extension's foundations are close to the neighbour's, the engineer's design and the party wall process will overlap. Ask the engineer whether their drawings will be suitable to share with a party wall surveyor.
How do you compare structural engineer quotes?
Send each engineer the same details:
- what you want to change, with a sketch or architect's drawing if you have one
- photos of the wall, crack or area, and of the rooms and loft above
- the age and type of house
- who your builder is, if you have one
- whether you need drawings for building control, or calculations only
Then compare:
- what is included, and what is extra
- whether a site visit is included
- the turnaround time
- whether they will answer building control's questions
- whether their fee is fixed or estimated
Citizens Advice says to check what insurance a trader has, and that professional indemnity insurance covers a trader who does faulty design work or gives bad advice [S6]. It is worth confirming that cover for any engineer you appoint.
Citizens Advice says a quote is a fixed price, while an estimate is just a rough guess, so you might end up paying more [S8]. It suggests getting written quotes from at least 3 different traders [S8].
Engineers who are not VAT registered won't add VAT. GOV.UK says a business must register for VAT if its taxable turnover for the last 12 months goes over £90,000 [S7]. Check every fee letter says whether VAT is included.
Who else is involved?
Your builder turns the design into work on site. Some builders work with an engineer they know and include the fee in their quote. Our builders page covers the trade.
Building control checks that the work meets the regulations. They will usually want the engineer's calculations before or during the work.
An architect or designer may produce the main drawings for an extension, with the engineer working alongside.
A surveyor looks at the general condition of a property. If a survey flags a structural concern, it may recommend an engineer. House survey costs explains surveys.
For the beam itself, steel beam (RSJ) costs explains what changes the price, and load-bearing walls explains how to tell what a wall does. For movement in foundations, underpinning covers the repair.
Jobs you might post
These are examples, not taken from real job posts.
- "Want to knock the kitchen and dining room together. Wall may be load-bearing. Need beam calculations and a drawing for building control."
- "Diagonal crack above the back door that seems to be getting wider. Looking for a structural engineer to inspect and report."
- "Planning a single-storey rear extension with large glazed doors. Need structural design to go with the architect's drawings."
Posting a job that needs an engineer
Photos of the wall or crack, the rooms above, and any drawings you already have are the most useful things to add. Your job goes to up to five matched local businesses [QZ2]. QuoteZila is free for customers and local businesses [QZ1].
Honest status: QuoteZila is new. We're starting in Cheshire, beginning with Crewe, Nantwich and Sandbach, and growing area by area. Anyone in the UK can still post a job or register a business. How fast you get quotes depends on how many local businesses have joined near you. Businesses can register and receive jobs straight away. We don't check insurance, qualifications or registrations, so please check these yourself before you hire.
Posting a job is not open yet
Questions about structural engineer fees
How much does a structural engineer cost?
This guide does not print a fee. A single visit to look at a crack is a very different job from beam calculations for building control, or a full structural design for a two-storey extension. Ask each engineer for a written fee that says what is included and what costs extra.
Do I need a structural engineer to remove a wall?
If the wall is load-bearing, usually yes. The Planning Portal says removing a load-bearing wall in a flat will require building control approval, and that you will be required to provide a report from a structural engineer with structural calculations.
What is the difference between a structural engineer and a surveyor?
A building surveyor looks at the general condition of a property. A structural engineer specialises in how the building stands up: loads, beams, foundations and movement. If a surveyor finds a structural concern, they may recommend an engineer.
Will the engineer deal with building control?
Ask. Some engineers send calculations straight to building control and answer their questions. Others give you the calculations and leave the submission to you or your builder. Find out before you agree the fee.
Can my builder size the steel beam instead?
Building control will normally want calculations for a structural beam. Some builders work with an engineer they know and include the fee in their quote. Either way, ask who is responsible for the design.
Do I need an engineer for cracks in my walls?
Not every crack is structural. If cracks are growing, wider at one end, or doors and windows are sticking, an engineer can tell you whether there is movement and whether it needs action. Tell your buildings insurer early if you suspect subsidence.
What insurance should a structural engineer have?
Citizens Advice says professional indemnity insurance covers a trader who does faulty design work or gives bad advice. Ask any engineer to show that theirs is in place for the work you need.
Does QuoteZila check structural engineers?
No. We don't check insurance, qualifications or registrations, so please check these yourself before you hire. You can report a quote or a business from your job page.
This page is general information, not professional or legal advice. QuoteZila does not check Gas Safe, WaterSafe, NFRC, NICEIC or other registrations against the register on your behalf: look them up yourself.
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Related pages
- Timber Frame Extension Cost: What to Ask. A timber frame extension in Cheshire is still an extension. Planning looks at appearance and size. Ask for the frame, the cladding and the ground.
- Two-storey extension: what changes the price. Two-storey extensions typically cost £1,000 to £2,500 per square metre in Master Builders guides. Compare drawings in Cheshire. QuoteZila does not set prices.
Sources
- QZ1: QuoteZila product fact. QuoteZila home and FAQ copy.
- QZ2: QuoteZila product fact. QuoteZila FAQ How does getting quotes work.
- S1: Single storey extension costs: a practical guide, Federation of Master Builders. Accessed 2026-11-02. https://www.fmb.org.uk/resource/single-storey-extension-costs-a-practical-guide-for-homeowners.html
- S2: Can I replace my grass lawn with artificial grass? (Common questions), Planning Portal (Interactive House). Accessed 2026-11-02. https://interactive.planningportal.co.uk/faqs/can-i-replace-my-grass-lawn-with-artificial-grass
- S3: What building regulations apply to internal walls?, Planning Portal. Accessed 2026-11-02. https://www.planningportal.co.uk/permission/common-projects/internal-walls/what-building-regulations-apply-to-internal-walls/
- S4: Building regulations approval, GOV.UK. Accessed 2026-11-02. https://www.gov.uk/building-regulations-approval
- S5: Party walls and building work, GOV.UK. Accessed 2026-11-02. https://www.gov.uk/party-walls-building-works
- S6: Before you get building work done (insurance), Citizens Advice. Accessed 2026-11-02. https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/before-you-get-building-work-done/
- S7: Register for VAT, GOV.UK. Accessed 2026-11-02. https://www.gov.uk/register-for-vat
- S8: Before you get building work done, Citizens Advice. Accessed 2026-11-02. https://www.citizensadvice.org.uk/consumer/getting-home-improvements-done/before-you-get-building-work-done/