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We know Windsor and Maidenhead's housing stock and what Royal Borough of Windsor & Maidenhead expects
Expert structural calculations for extensions, lofts, and renovations in Windsor and Maidenhead, Berkshire.
Based in Manchester, with engineers around the country for site visits. We've worked extensively across Berkshire and know Windsor and Maidenhead well — the Medieval → modern Brick & stone, the party wall situations that come with them.
More importantly, we know how Royal Borough of Windsor & Maidenhead’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 Windsor and Maidenhead. With 220+ calculations completed across Berkshire, our engineers understand the area's Medieval → modern Brick & stone properties, ensuring every design accounts for local building characteristics and River gravels ground conditions. Our most recent project in the area was a single storey extension completed in Jan 2026.
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 Windsor and Maidenhead
New-build
Single storey extension
Two-storey extension
Single storey extension
Loft conversion
Send us your plans
A fixed price before you commit. No obligation, no chasing.
What people say
Frequently Asked
It depends on the size and complexity of your project, so we don't publish a price range for Windsor and Maidenhead. 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 Windsor and Maidenhead's Medieval - modern properties. Our engineers aim to understand the specific requirements of your property from Brick & stone construction, ensuring calculations that respect the original structure while meeting modern standards.
Windsor and Maidenhead typically has River gravels. River terrace deposits. We factor these conditions into our foundation designs, which may affect the depth and type of foundations required.
On a full plans application, Royal Borough of Windsor & Maidenhead 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 Windsor and Maidenhead and the surrounding Berkshire 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 Windsor and Maidenhead's unique characteristics helps us deliver precise structural solutions.
Structural engineering services in Windsor and Maidenhead
Structural Engineering Excellence in Berkshire
Choosing the right structural engineer means finding someone who truly understands your area. We specialize in Berkshire properties, working regularly with everything from Medieval → modern homes built with Brick & stone. This local expertise means our designs are written to satisfy Royal Borough of Windsor & Maidenhead building regulations.
Foundation Design for Berkshire’s Soil Types
Successful structural projects begin with proper foundation design. Berkshire’s typical River gravels 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
Historic townhouses, riverside homes This diversity means we’ve developed expertise across all property types – whether you’re extending a period property near Windsor Castle; Maidenhead Bridge or renovating a modern home with easy access to Elizabeth line; M4; Great Western Main Line.
We maintain strong working relationships with Royal Borough of Windsor & Maidenhead building control, streamlining approvals for your project. Our calculations are approved by building control, or you get a refund.
Serving Berkshire and Surrounding Areas
We provide structural engineering services for all types of residential projects across Berkshire:
• 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
Request Your Free Berkshire Structural Engineering Quote
Starting your project? Get in touch with PorthouseDean for structural calculation pricing in Berkshire. You’ll have a detailed, fixed-fee 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.
