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We know Hertfordshire's housing stock and what Hertfordshire County Council expects
Nationwide-calibre support for home projects across Hertfordshire.
Based in Manchester, with engineers around the country for site visits. We've worked extensively across Hertfordshire — the Medieval → modern Brick & flint, timber frame, the party wall situations that come with them.
More importantly, we know how Hertfordshire County Council’s building control team operates and we write our calculations to match. That saves time on site and avoids queries coming back.
Local knowledge
PorthouseDean provides structural engineering for extensions, knock-throughs, loft conversions, and two-storey extensions in Hertfordshire. With 240+ calculations completed across Hertfordshire, our engineers understand the area's Medieval → modern Brick & flint, timber frame properties, ensuring every design accounts for local building characteristics and Chalk ground conditions. Our most recent project in the area was a single storey extension completed in Dec 2025.
Structural engineering is the core of it. It isn’t where we stop.
The calculations and drawings are ours. So are the things around them that usually land on you: a date you can plan around, one place where everyone sees the same documents, and the change of mind nobody priced for. More than 9,000 projects since 2012 have run through the same process, from a single wall removal to a whole new build.
Three things you always know
Every job runs through the same process, so every customer gets the same three answers.
The price, before you commit
Tell us about the project and we’ll tell you the price and the steps that follow. No hourly rate. If the job changes, there is a free change request on every job.
The turnaround, chosen by you
Pick how fast you need it, and pay less if you can wait. You get a date to work back from.
Every step, in one place
Never wonder where it’s up to — just look. Your project hub shows what is happening now, what is next and anything we need from you, with your drawings, documents and invoice alongside. Share it directly with everyone involved in your project.
One document for building control, one for your builder
Building control gets the calculations. Your builder gets the contractor pack. If either of them has a question about the structure, it comes to us, not to you. How we check and what the process looks like.
Fixed fee. No surprises after you've committed.
No extras for building control queries.
Recent Projects Near Hertfordshire
Single storey extension
Two-storey extension
Two-storey extension
Single storey extension
Other
Send us your plans
A fixed price before you commit. No obligation, no chasing.
What people say
Areas We Cover in Hertfordshire
Select your area below for local project data and a quote tailored to your location.
Frequently Asked
It depends on the size and complexity of your project, so we don't publish a price range for Hertfordshire. Tell us about your project and you get a clear, fixed-fee quote before you commit.
Sure, we have worked on a wide variety of Hertfordshire's Medieval - modern properties. Our engineers aim to understand the specific requirements of your property from Brick & flint, timber frame construction, ensuring calculations that respect the original structure while meeting modern standards.
Hertfordshire typically has Chalk. Chalk with superficial clay. We factor these conditions into our foundation designs, which may affect the depth and type of foundations required.
On a full plans application, the council has five weeks to decide, or longer if you both agree it in writing (regulation 14A of the Building Regulations 2010). On a building notice there is no plans decision: building control checks the work, and our calculations, as it goes. If they raise a question about the structure, your engineer answers it.
We provide structural calculations throughout Hertfordshire and the surrounding Hertfordshire area. Our engineers regularly work on projects across the region, and you choose the delivery date that suits you.
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.
On the date you choose when you book. The price follows the date: pick a later one and it costs less, or an earlier one if you need them sooner.
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. The moments that cost you come later: when building control query something, or your builder can't follow the drawings. That's why BC queries, an amendment and a virtual site visit are included — it's where projects actually succeed or fail.
Local Area Information
Understanding Hertfordshire's unique characteristics helps us deliver precise structural solutions.
Structural engineering services in Hertfordshire
Hertfordshire Structural Calculations You Can Trust
Local knowledge makes all the difference in structural engineering. Our team has in-depth understanding of Hertfordshire’s diverse property types, spanning Medieval → modern with their typical Brick & flint, timber frame. Every calculation we produce considers local building control expectations at Hertfordshire County Council, giving you confidence in approval.
Local Geology Expertise for Hertfordshire Projects
Every structural calculation must respond to site-specific ground conditions. In Hertfordshire, we commonly encounter Chalk, requiring particular foundation solutions. Chalk with superficial clay This geological understanding informs all our work, from simple extensions to complex structural alterations.
Hertfordshire Property Specialists
The area’s diverse building stock – Villages, market-town cottages – means varied structural challenges. From period properties around Hatfield House; Knebworth House to modern homes near East Coast Main Line; M1, we’ve engineered solutions across Hertfordshire.
Working regularly with Hertfordshire County Council means our calculations align with their expectations. We’ve built a track record of first-time approvals, saving you time and frustration.
Coverage Across Hertfordshire
Operating throughout Hertfordshire and surrounding areas (population: 1.2 M), our services include:
• Loft conversion and roof extension calculations
• Extension designs – all configurations
• Internal structural alterations
• Steel beam and RSJ specifications
• Foundation and underpinning calculations
Get Your Hertfordshire Structural Calculations Quote
Ready to start your project? Contact PorthouseDean today for a competitive quote on structural calculations in Hertfordshire. You’ll get a clear, fixed-price quotation before you commit.
Ready to get started?
Send us your plans and you'll have a clear, fixed price before you commit. Or give us a call.
