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Residential structural engineering that doesn't leave you guessing
Trusted by builders and architects in Hertsmere for reliable calculations. Request your structural calculations quote – fast, reliable, trusted.
Offices in Manchester, London and Gloucester, with engineers around the country for site visits. We've worked extensively across Hertfordshire and know Hertsmere well — the Post-war → modern Brick semis, the party wall situations that come with them.
More importantly, we know how Hertsmere Borough Council’s building control team operates and we write our calculations to match. That saves time on site and avoids queries coming back.
PorthouseDean provides structural engineering for extensions, knock-throughs, loft conversions, and two-storey extensions in Hertsmere. With 240+ calculations completed across Hertfordshire, our engineers understand the area's Post-war → modern Brick semis properties, ensuring every design accounts for local building characteristics and London Clay ground conditions. Our most recent project in the area was a single storey extension completed in Dec 2025.
We don't do commercial. We don't do bridges. We do extensions, loft conversions, knockthroughs, new builds — and we've done over 240+ 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.
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.
The number we quote is the number you pay. No extras bolted on for BC queries, no awkward invoice three months later.
Fixed fee quote within 24 hours. No obligation, no chasing.
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.
Having completed 240+ projects across Hertfordshire, we can confirm structural calculations typically start from £500 + VAT.
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.
Understanding Hertsmere's unique characteristics helps us deliver precise structural solutions.
With extensive experience across Hertfordshire, our structural engineers combine technical excellence with detailed understanding of local building stock. From Post-war → modern properties featuring Brick semis, we’ve worked on hundreds of projects throughout the area. Our calculations are specifically designed to meet Hertsmere Borough Council requirements, ensuring smooth approval processes.
Calculations That Account for Hertfordshire’s Geology
Ground conditions vary significantly across regions. Hertfordshire presents its own considerations with London Clay. Clay with sand lenses Our engineers have extensive experience designing foundations for these local conditions, essential for any extension, conversion, or alteration project.
We regularly work with Suburban semis throughout Hertfordshire. Whether you’re renovating near Radlett Woods or extending a property with convenient access to West Coast Main Line, we bring relevant local experience.
Hertsmere Borough Council building control knows our work and trusts our calculations. This established reputation translates to smoother approval processes and fewer obstacles for your project.
From our base serving Hertfordshire (population: 110 k), we provide structural engineering services for all types of residential projects:
• Loft conversions and dormer extensions
• Single and double-storey rear extensions
• Side return and wrap-around extensions
• Internal alterations and load-bearing wall removals
• Foundation design and underpinning calculations
Hertfordshire Structural Engineering – Request Your Quote
Begin your project with confidence. Contact PorthouseDean for structural calculation services in Hertfordshire. Our fixed-fee quotations arrive within one working day.
Send us your plans for a fixed-fee quote within 24 hours. Or call us — we actually answer.