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 Egham?
In Egham, a structural alteration typically costs £5,000–£10,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Prices across the South East are typically 12% above the UK average for this kind of work, which is reflected in the range for Egham. 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 biggest cost drivers are:
- Flush or downstand beam
- Floor and ceiling repairs
- Party wall involvement
- 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 Egham?
Approvals for a structural alteration in Egham follow the rules for 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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
The work we manage on a structural alteration:
- Structural engineer’s calculations and drawings
- Steel beam supply and installation on padstones
- Temporary propping
- Building control sign-off
- Fire protection to the steel
- Building control application
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 Egham
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
If your home is in Egham or close by in Staines, Ashford and Windsor, a free home visit is the first step.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about structural alterations in Egham
How much does a structural alteration cost in Egham?
In Egham, 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.
What fire protection does a steel need?
Usually fire-rated plasterboard or intumescent paint, as building control requires.
How long does a knock-through take?
Usually 1 to 2 weeks on site, plus a few days for plastering to dry.
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.
Who approves a structural alteration in Egham?
Planning matters in Egham go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
