Calculations prepared by IStructE Engineers

Structural Engineers for Extensions & Alterations.

We prepare structural drawings and calculations for all types of extensions and alterations, including single-storey, double-storey, side, rear and more.

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> 5,000 Drawings delivered across London homes.

Independent drawings and calculations prepared by IStructE Chartered Engineers.

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Providing structural designs that support safe construction, meet regulations, and are tailored to your project.

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Structural Survey

Structural inspections carried out quickly, so your extension design can begin without delay.

Structural Drawings

Detailed drawings tailored to your home, ensuring your extension is safe, compliant, and build-ready.

Structural Calculations

Precise load-bearing calculations for beams, foundations, and walls, giving your builder clear instructions.

Planning Permission

Guidance on whether your project falls under permitted development or requires a planning application.

Building Regulations

Full compliance with UK Building Regulations, with drawings and specifications ready for Structural Building Control approval.

Chartered Expertise

All designs and calculations are carried out by an IStructE Chartered Engineer for complete peace of mind.

> 1,100

Extensions, lofts, and conversions completed across London since 2020.

We’re here for you. Our team is available to answer your questions, explain the process, and provide guidance at every stage of your project.

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Every extension reviewed by an IStructE professional.

Survey to drawings in as little as 5 working days.

Clear, compliant designs your builder can follow.

Why homeowners choose us

Fast, compliant, and practical designs — tailored to your extension.

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We keep your project moving. From measured survey to draft extension drawings, our process is designed for speed and clarity.

Compliance built in. Every design meets UK Building Regulations, giving your builder and Building Control everything they need without delays.

Included with every project. Clear, build-ready designs and full support at every stage.

Site Visit

Structural Calculations

Structural Plans

Ongoing Support

Connect with Vetted Builders

Dedicated Chartered Engineer

Advice

Structural Survey

Site Visit

Structural Calculations

Structural Plans

Ongoing Support

Connect with Vetted Builders

Dedicated Chartered Engineer

Advice

Structural Survey

Site Visit

Structural Calculations

Structural Plans

Ongoing Support

Connect with Vetted Builders

Dedicated Chartered Engineer

Advice

Structural Survey

Fully insured with AXA, covering public and professional liability for complete peace of mind.

Everything you need, included as standard. No hidden extras, no unexpected costs — just clear, build-ready designs and full support from start to finish.

AXA Liability Cover

Up to £1M PI and PL Cover

Trusted collaborations

Chosen by architects for structural expertise

From concept sketches to final approvals, we work closely with leading architecture practices to deliver safe, compliant, and practical structural solutions. Our collaborative approach ensures projects move forward smoothly, without delays or uncertainty.

How it works

Our step-by-step process for a stress-free extension

From the first consultation to final sign-off, we handle every stage of your extension with clarity, compliance, and care.

Step 1

Get a Quote

Fill out our online form with your project details. We’ll review the information and send you a tailored quote promptly.

Step 2

Site Visit & Survey

One of our Chartered Structural Engineers will visit your property to take precise measurements and assess the extension requirements.

Step 3

Structural Calculations & Drawings

We prepare detailed structural calculations and drawings, ensuring your extension is fully compliant and build-ready.

Step 4

Planning & Building Regulations

If approvals are required, we provide the documents and guidance needed to secure planning permission and Building Control sign-off.

Step 5

Project Delivery

Within as little as 5 working days, your final structural package is ready — giving your builder everything they need to get started.

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