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Structural Engineers in the City of London

Residential structural engineering that doesn't leave you guessing

Compliant structural solutions for unique City of London properties. Speak to our engineers today and get peace of mind for your project.

1,500+
Projects across Greater London
100%
BC approval record
4.6 ★
Google rating

We know City of London's housing stock and what City of London Corporation expects

Offices in Manchester, London and Gloucester, with engineers around the country for site visits. We've worked extensively across Greater London and know City of London well — the Medieval → modern towers Steel & glass high-rises, the party wall situations that come with them.

More importantly, we know how City of London Corporation’s building control team operates and we write our calculations to match. That saves time on site and avoids queries coming back.

Local knowledge

Projects completed across City of London and surrounding areas
Familiar with River alluvium ground conditions and what that means for your foundations
Experience with Medieval → modern towers properties and the structural challenges they present
Working near St Paul’s Cathedral; Bank of England and the surrounding neighbourhood
Site visits arranged locally when your project needs one

PorthouseDean provides structural engineering for extensions, knock-throughs, loft conversions, and two-storey extensions in City of London. With 1,500+ calculations completed across Greater London, our engineers understand the area's Medieval → modern towers Steel & glass high-rises properties, ensuring every design accounts for local building characteristics and River alluvium ground conditions. Our most recent project in the area was a single storey extension completed in Jan 2026.

Houses are all we do. That specialism matters when something goes awkward.

We don't do commercial. We don't do bridges. We do extensions, loft conversions, knockthroughs, new builds — and we've done over 1,500+ of them with a 100% building control success record.

That specialism means when your project throws up something unexpected — and they always do — we've seen it before. We know what works, what building control will push back on, and what your builder actually needs on the page to build from.

1,500+
Residential projects
100%
BC approval rate
4.6 ★
Google reviews

The quote's the easy part. It's three weeks later that matters.

The difference between structural engineers doesn't show up in a quote. It shows up when your builder's on site and something doesn't add up. When building control come back with a query. When the design changes halfway through and someone needs new calcs yesterday.

Our calculations are detailed enough that your builder can work from them without ringing anyone. When BC come back with a query, we deal with it — as many as they want. If they want something changed, we change it.

Project changes? Every quote includes a free amendment because we know designs evolve. Need to speak to your engineer? We give you a direct booking link for meetings, and our tech support team handles urgent queries whenever you need them.

A builder standing around waiting for a structural answer costs real money. We're the engineers who pick up the phone.

Fixed fee. No surprises after you've committed.

The number we quote is the number you pay. No extras bolted on for BC queries, no awkward invoice three months later.

Full structural calculations
Detailed enough for your builder to work from without calling anyone. Standard delivery in 10 working days — or as little as 1.
Unlimited BC queries
Building control come back with questions — we deal with every one. If they want changes, we make them.
One free amendment
Projects change — we know that. One design amendment included in every quote as standard.
Virtual site visit
A face-to-face video call with your engineer to talk through specific design requirements. Included in your quote.
Direct engineer access
A booking link to schedule meetings with your engineer directly, plus tech support for urgent queries.
Quote within 24 hours
Often much quicker. A fixed fee so you can plan your budget or quote your own client with confidence.

Recent Projects Near City of London

Example of a single storey extension — the type of work we carry out in City of London

Single storey extension

StainesTWSep 2025
Example of a single storey extension — the type of work we carry out in City of London

Single storey extension

AshfordTWSep 2025
Example of a single storey extension — the type of work we carry out in City of London

Single storey extension

Englefield GreenTWSep 2025
Example of a single storey extension — the type of work we carry out in City of London

Single storey extension

TeddingtonTWSep 2025
Example of a single storey extension — the type of work we carry out in City of London

Single storey extension

SunburyTWSep 2024

Send plans. Get a quote. We handle the rest.

1
Send us your plans
Drawings, sketches, whatever you've got. We'll take it from there.
2
Fixed fee quote within 24 hours
Often much quicker. A clear number so you can plan your budget or quote your own client with confidence.
3
Virtual site visit with your engineer
Put a face to the name, talk through the specifics. Included in your quote — no physical visit needed to get started.
4
Calculations in 10 working days (or as little as 1)
Signed off and ready for City of London Corporation. Detailed enough to build from.
5
We deal with building control
However many queries they come back with, we handle them. If they want something changed, we change it.

Send us your plans

Fixed fee quote within 24 hours. No obligation, no chasing.

What people say

★★★★★
I've used PorthouseDean engineers for many of our clients and my personal project. I find their pricing fair to reflect the quality work that has been produced. Definitely recommend.
— Clinton Johnson · Trustpilot
★★★★★
I was referred to them by the building control designers. I found them responsive and helpful. The engineering came through quickly for building control and as I needed them to get contractors quotes. Fair and reasonable price for the excellent service.
— Oasis · Trustpilot
★★★★★
The internal structural walls changed at least 3 times and the engineer assigned to me was very accommodating with the changes. I liked the fact that the work they do is peer-checked. Would not hesitate to use them again.
— Phil Neo · Trustpilot

Frequently Asked

If you're removing a wall, converting a loft, building an extension, or doing anything that affects the structure of your house — yes. Building control will require structural calculations before they sign off the work.

A virtual site visit is included in every quote — it's a chance to put a face to the name and talk through specific design requirements with your engineer. But we don't believe a physical visit is necessary for most residential projects. Working remotely allows us to be more economical while maintaining the same quality throughout. If your project does need a physical visit, we have engineers around the country who can arrange one.

Quote within 24 hours of receiving your plans — often much quicker. Standard delivery is 10 working days, but we can turn calculations around in as little as 1 working day if you need them urgently.

Based on our 1,500+ projects across Greater London, structural calculations typically start from £500 + VAT depending on complexity.

Fees depend on the scope and complexity of your project. We provide clear, fixed-fee quotes within 24 hours so you know exactly what you'll pay before we start. No hidden costs, no extras for building control queries.

Every quote includes one free amendment because we know projects change — that's normal. Beyond that, we'll quote any further changes clearly so there are no surprises.

The quote's not the product — the project is. A cheaper set of calculations might get you through the door, but when building control query something or your builder can't follow the drawings, that's when it costs you. We include BC queries, an amendment, and a virtual site visit because that's where projects actually succeed or fail.

Local Area Information

Understanding City of London's unique characteristics helps us deliver precise structural solutions.

Population
9 k
Building Era
Medieval → modern towers
Soil Conditions
River alluvium
Local Authority
City of London Corporation
Housing Stock
Office conversions, luxury apartments
Transport Links
Central, Northern lines; Thameslink
Engineering Note: River terrace deposits

About Our City of London Structural Engineering Services

Structural Engineering Excellence in Greater London

Choosing the right structural engineer means finding someone who truly understands your area. We specialize in Greater London properties, working regularly with everything from Medieval → modern towers homes built with Steel & glass high-rises. This local expertise ensures our designs satisfy City of London Corporation building regulations efficiently.

Foundation Design for Greater London’s Soil Types

Successful structural projects begin with proper foundation design. Greater London’s typical River alluvium presents specific engineering requirements. River terrace deposits We incorporate this geological knowledge throughout our calculations, ensuring safe, durable foundations for extensions, conversions, and renovations.

Local Expertise, Professional Service

Office conversions, luxury apartments This diversity means we’ve developed expertise across all property types – whether you’re extending a period property near St Paul’s Cathedral; Bank of England or renovating a modern home with easy access to Central, Northern lines; Thameslink.

We maintain strong working relationships with City of London Corporation building control, streamlining approvals for your project. Our structural calculations are accepted first time, avoiding costly delays.

Structural Engineering Services Throughout Greater London

We provide comprehensive structural calculations across Greater London (population: 9 k), covering:

• Loft conversions and dormer additions
• Rear extensions – single and double storey
• Side and wrap-around extensions
• Load-bearing wall removal calculations
• Foundation designs and underpinning assessments

Request Your Free Greater London Structural Engineering Quote

Starting your project? Get in touch with PorthouseDean for structural calculation pricing in Greater London. Expect our detailed, fixed-fee quotation within 24 hours.

Ready to get started?

Send us your plans for a fixed-fee quote within 24 hours. Or call us — we actually answer.