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 Brentwood?
In Brentwood, a structural alteration typically costs £4,750–£10,000 for a typical knock-through with steel beam, including VAT at 20% (standard rate). That range is adjusted for the East of England, where domestic building work typically costs around 6% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical knock-through with steel beam | £4,750–£10,000 |
| Higher specification | £10,000–£12,500 |
Your quote will depend mainly on:
- Party wall involvement
- What sits above the wall
- Floor and ceiling repairs
- Flush or downstand beam
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a structural alteration in Brentwood?
Whether you need planning permission depends on your house and its location 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
On a typical structural alteration we handle:
- Fire protection to the steel
- Building control application
- Temporary propping
- Structural engineer’s calculations and drawings
- Steel beam supply and installation on padstones
- Party wall notices where needed
How long does it take?
Allow 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 Brentwood
Across the East of England, 1930s and post-war semis, newer estates and rural cottages all feature, each with different extension and loft options.
If your home is in Brentwood or close by in Billericay, Upminster and Hornchurch, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about structural alterations in Brentwood
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.
What fire protection does a steel need?
Usually fire-rated plasterboard or intumescent paint, as building control requires.
How much does a structural alteration cost in Brentwood?
In Brentwood, a structural alteration typically costs £4,750–£10,000 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 Brentwood?
Planning matters in Brentwood go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Do I need a party wall notice?
In England and Wales, if the beam sits in a party wall, yes.
