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 Ruislip?
In Ruislip, a structural alteration typically costs £5,750–£12,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). That range is adjusted for London, where domestic building work typically costs around 30% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical knock-through with steel beam | £5,750–£12,500 |
| Higher specification | £12,500–£15,500 |
The biggest cost drivers are:
- Span of the opening
- Flush or downstand beam
- Moving radiators, sockets and pipes
- Party wall involvement
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 Ruislip?
Before anything is built in Ruislip, we confirm which approvals apply 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.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
On a typical structural alteration we handle:
- Fire protection to the steel
- Structural engineer’s calculations and drawings
- Steel beam supply and installation on padstones
- Party wall notices where needed
- Building control application
- Temporary propping
How long does it take?
The build itself usually takes 1 to 2 weeks on site for a typical knock-through. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Ruislip
Victorian and Edwardian terraces dominate many London streets, which is why side return, wraparound and mansard projects are so common here.
Projects in Ruislip (HA4) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about structural alterations in Ruislip
Do you build structural alterations in Ruislip?
Yes. We build structural alterations across Ruislip, including postcodes HA4. Every project starts with a free home visit.
Do I need building regulations approval?
Yes. Removing a load-bearing wall is building work that needs approval, with calculations for the beam.
Can the beam be hidden?
Often, by setting it within the ceiling depth. It depends on the joists and span.
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 Ruislip?
In Ruislip, a structural alteration typically costs £5,750–£12,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
