What is a structural alteration?

A structural alteration changes how a house carries its loads, most often by removing a load-bearing wall and replacing it with a steel beam. It is how kitchens and dining rooms become open-plan, and how extensions are joined to the original house.
How much does a structural alteration cost in Epsom?
In Epsom, a structural alteration typically costs £5,000–£10,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for Epsom are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical knock-through with steel beam | £5,000–£10,500 |
| Higher specification | £10,500–£13,000 |
The main things that change the cost:
- Moving radiators, sockets and pipes
- Party wall involvement
- Span of the opening
- What sits above the wall
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a structural alteration in Epsom?
Here is how the rules work for a structural alteration in England. In England removing a load-bearing wall does not need planning permission but does need building regulations approval with an engineer’s calculations. If the beam bears on a party wall, a party wall notice must be served.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
We check this for your address before design work starts, so there are no surprises later.
What we handle
The work we manage on a structural alteration:
- Structural engineer’s calculations and drawings
- Steel beam supply and installation on padstones
- Building control sign-off
- Building control application
- Making good, plastering and flooring repairs
- Party wall notices where needed
How long does it take?
The build itself usually takes 1 to 2 weeks on site for a typical knock-through. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Epsom
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Epsom sits in Surrey, about 15 miles north-east of Guildford. We cover the whole of Epsom, including postcodes KT17 and KT19.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about structural alterations in Epsom
How much does a structural alteration cost in Epsom?
In Epsom, a structural alteration typically costs £5,000–£10,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Who approves a structural alteration in Epsom?
Planning matters in Epsom go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
What fire protection does a steel need?
Usually fire-rated plasterboard or intumescent paint, as building control requires.
How do I know if a wall is load-bearing?
Only a survey can confirm it. Walls that carry floor joists, roof loads or walls above are load-bearing. We check on site and the engineer confirms.
Do I need building regulations approval?
Yes. Removing a load-bearing wall is building work that needs approval, with calculations for the beam.
