Calculations and drawings for Stevenage renovations.
Based in Manchester, with engineers around the country for site visits. We've worked extensively across Hertfordshire and know Stevenage well — the New Town (1950s) → modern Concrete panels, brick, the party wall situations that come with them.
More importantly, we know how Stevenage 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 Stevenage. With 240+ calculations completed across Hertfordshire, our engineers understand the area's New Town (1950s) → modern Concrete panels, brick properties, ensuring every design accounts for local building characteristics and Boulder clay ground conditions. Our most recent project in the area was a single storey extension completed in Dec 2025.
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.
Every job runs through the same process, so every customer gets the same three answers.
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.
Pick how fast you need it, and pay less if you can wait. You get a date to work back from.
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.
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.
No extras for building control queries.
A fixed price before you commit. No obligation, no chasing.
It depends on the size and complexity of your project, so we don't publish a price range for Stevenage. 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 Stevenage's New Town (1950s) - modern properties. Our engineers aim to understand the specific requirements of your property from Concrete panels, brick construction, ensuring calculations that respect the original structure while meeting modern standards.
Stevenage typically has Boulder clay. Boulder clay. We factor these conditions into our foundation designs, which may affect the depth and type of foundations required.
On a full plans application, Stevenage Borough 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 Stevenage 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.
Understanding Stevenage's unique characteristics helps us deliver precise structural solutions.
Professional Structural Calculations for Hertfordshire Properties
Your project deserves engineers who know Hertfordshire inside and out. We work extensively with the area’s building heritage – New Town (1950s) → modern constructions using Concrete panels, brick. Our familiarity with Stevenage Borough Council processes means fewer queries and fewer complications for your project.
Structural Calculations Tailored to Hertfordshire Properties
Every area has its challenges. In Hertfordshire, we regularly work with Boulder clay, which requires specific foundation design approaches. Boulder clay Our structural engineers account for these local conditions in every calculation, ensuring your extension, loft conversion, or structural alteration is built on solid foundations.
From New-town townhouses & flats, we’ve worked on projects throughout Hertfordshire. Whether your property sits near Fairlands Valley Park or benefits from proximity to East Coast Main Line, we understand the local context.
Our established relationship with Stevenage Borough Council building control helps expedite your project. We consistently deliver calculations that meet their standards, minimising delays and resubmissions.
We provide structural engineering services for all types of residential projects across Hertfordshire:
• 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
Structural Calculations Quote for Your Hertfordshire Project
Ready to move forward? Contact PorthouseDean for structural engineering services in Hertfordshire. We provide clear, competitive quotes within one business day.
Send us your plans and you'll have a clear, fixed price before you commit. Or give us a call.