From lofts to new builds, we support residential designs in Hillingdon.
Based in Manchester, with engineers around the country for site visits. We've worked extensively across Greater London and know Hillingdon well — the Mid-century suburbs Brick semis, dormer bungalows, the party wall situations that come with them.
More importantly, we know how Hillingdon 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 Hillingdon. With 1,500+ calculations completed across Greater London, our engineers understand the area's Mid-century suburbs Brick semis, dormer bungalows 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 Jan 2026.
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 Hillingdon. 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 Hillingdon's Mid-century suburbs properties. Our engineers aim to understand the specific requirements of your property from Brick semis, dormer bungalows construction, ensuring calculations that respect the original structure while meeting modern standards.
Hillingdon typically has London Clay. Clay over chalk. We factor these conditions into our foundation designs, which may affect the depth and type of foundations required.
On a full plans application, Hillingdon 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 Hillingdon and the surrounding Greater London 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 Hillingdon's unique characteristics helps us deliver precise structural solutions.
With extensive experience across Greater London, our structural engineers combine technical excellence with detailed understanding of local building stock. From Mid-century suburbs properties featuring Brick semis, dormer bungalows, we’ve worked on hundreds of projects throughout the area. Our calculations are specifically designed to meet Hillingdon Council requirements, ensuring smooth approval processes.
Calculations That Account for Greater London’s Geology
Ground conditions vary significantly across regions. Greater London presents its own considerations with London Clay. Clay over chalk Our engineers have extensive experience designing foundations for these local conditions, essential for any extension, conversion, or alteration project.
We regularly work with 1930s semis, post-war terraces throughout Greater London. Whether you’re renovating near Heathrow Airport, Ruislip Woods or extending a property with convenient access to Piccadilly line, National Rail, we bring relevant local experience.
Hillingdon Council building control knows our work and trusts our calculations. This established reputation translates to smoother approval processes and fewer obstacles for your project.
Coverage Across Greater London
Operating throughout Greater London and surrounding areas (population: 310 k), 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
Greater London Structural Engineering – Request Your Quote
Begin your project with confidence. Contact PorthouseDean for structural calculation services in Greater London. Our fixed-fee quotations arrive within one working day.
Send us your plans and you'll have a clear, fixed price before you commit. Or give us a call.