Structural alteration feasibility study
A study of whether a proposed structural alteration is feasible, with the options and likely implications before you commit to a design.
About this service
Before you pay for full architectural drawings, it helps to know whether the big idea is structurally sensible. Can that spine wall come out to create an open-plan ground floor? Will the existing walls take another storey? Is a basement realistic under a Victorian terrace on London Clay? A structural alteration feasibility study answers questions like these early, sets out the options and explains what each one is likely to involve.
The study starts with the building as it is. We look at how the existing structure carries its loads, what it is built from, how previous owners have altered it and what condition it is in. Only then do we test the proposal against it. That order matters, because many London houses have been altered several times, and the hidden history often decides which option is practical.
Buyers find this especially useful. If you are purchasing a property with plans to extend, open up or convert, a study before exchange can flag the alterations that will be costly, need a party wall process or depend on a neighbour. Architects use it too, to get structural input before the design is fixed. For a check on condition rather than alterations, a General Structural Inspection report is usually the better fit.
When you need it
- You're thinking about major alterations and want to know what's possible
- You're buying a property and want to check your plans are achievable
- Your architect needs early structural input
What's included
- Review of the existing structure
- Structural options for the proposed alteration
- Key risks and implications
- Recommendations
How it works
- Understand your ambitionsWe talk through what you want to achieve, review any sketches or estate agent plans, and agree which alterations the study should test so the scope is clear from the start.
- Inspect the existing structureWe visit to identify load-bearing walls, floor spans, roof structure, chimney breasts and signs of past movement, recording anything that limits what can be done.
- Develop and compare optionsFor each alteration we set out one or more structural approaches, such as steel frames, new piers or foundation changes, with their practical implications and main risks.
- Report with recommendationsWe issue a clear report recommending a preferred way forward and noting any further surveys needed. It goes through our three-step quality control process, with final sign-off by our Head of Engineering.
What you receive
What a feasibility study can and cannot tell you
A feasibility study is about direction, not detail. It will tell you that removing a wall is achievable with a steel beam on new padstones, or that adding a mansard will need the party walls checked and possibly strengthened. It will not size every member, because the design is not fixed yet. Where we cannot see inside a wall or below a floor, we say so and suggest targeted opening-up rather than guessing.
Most of the big risks in London alterations are predictable. Ground conditions, neighbouring structures, trees close to foundations and the Party Wall etc. Act 1996 all shape what is sensible. Flagging them early lets you budget time as well as money. When you are ready to proceed, our guide to removing a wall and guide to adding a storey explain the next stages.
Frequently asked questions
Should I get a structural engineer before buying a house I want to extend?
If your plans depend on significant structural changes, it is worth it. A feasibility study before exchange can show whether removing walls, going up or digging down is realistic, and what each option is likely to involve. It will not give you construction costs, but it identifies the issues that drive cost and programme, so you can make an informed decision or renegotiate.
What is included in a structural feasibility study?
We review the existing structure, set out the structural options for each proposed alteration, highlight key risks such as party walls, ground conditions or hidden defects, and make recommendations. The study is written in plain English for owners and buyers, with enough technical content for an architect to develop the design from it.
How much does a structural feasibility study cost in London?
Our structural alteration feasibility study starts from £600 + VAT. The fee depends on the size of the building and how many alterations you want assessed. We confirm a fixed fee in writing before starting, and our typical turnaround is 10 working days. Our guide to structural engineer costs explains how fees vary.
Can a feasibility study replace structural calculations?
No. It sets out the approach, but Building Control will need detailed calculations and drawings once the design is fixed. The study does make that later stage quicker, because the structural principles are already agreed, the risky areas have been looked at and your architect has designed around realistic structural zones.