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  • About Us
    • Our Practice
    • Meet the Team
    • Careers
    • Testimonials
  • Locations
  • For Architects
  • Services
    • Extensions
    • New Build Homes
    • Home Renovation
    • Loft Conversion
    • Basements
    • Structural Engineer Calculations
    • Structural Engineering Drawings
    • Lift Apertures
  • Process
    • Quality Assurance
  • Advice
    • Industry Professionals
    • Homeowners
    • Careers
  • Get In Touch
  • Become an Architectural Partner

South East & East England - 0208 183 4321

South West, Wales & Midlands - 01452 346 156

North England & Scotland - 0161 820 3230

Advice Centre

All Posts Advice Centre Building Control Careers Extensions Foundations Global Guides Homeowners Industry Professionals Load-Bearing Walls Loft Conversions Portfolio Retaining Walls Steel Beams Timber Floors & Roofs

Adding a First Floor Extension Over an Existing Ground Floor Extension

Advice Centre

Posted on March 31, 2026

Loading a first floor over an existing single-storey extension is feasible in many cases — but the foundation adequacy must be confirmed before design can proceed. Here’s what the investigation involves.

Tags: extensions, supporting

Can a Wall on Strip Foundations Be Used to Retain Ground?

Advice Centre

Posted on March 31, 2026

External walls are not automatically retaining walls. Small retaining walls can sometimes be designed without bespoke engineering — but you need to know the limits and your soil type.

Tags: extensions, supporting

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