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 Bournemouth?
In Bournemouth, a structural alteration typically costs £4,500–£9,750 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Prices in the South West sit near the national average for this kind of work, and the range for Bournemouth reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical knock-through with steel beam | £4,500–£9,750 |
| Higher specification | £9,750–£12,000 |
The main things that change the cost:
- Flush or downstand beam
- What sits above the wall
- Party wall involvement
- Moving radiators, sockets and pipes
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a structural alteration in Bournemouth?
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.
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:
- Steel beam supply and installation on padstones
- Making good, plastering and flooring repairs
- Fire protection to the steel
- Party wall notices where needed
- Building control application
- Structural engineer’s calculations and drawings
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 Bournemouth
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
We work across Bournemouth and neighbouring areas such as Christchurch, Poole and New Milton. Postcodes we cover in Bournemouth include BH1, BH2, BH7 and BH10.
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 pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about structural alterations in Bournemouth
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.
How long does a structural alteration take in Bournemouth?
Typically 1 to 2 weeks on site for a typical knock-through. Design and approvals beforehand usually take 6 to 12 weeks.
How much does a structural alteration cost in Bournemouth?
In Bournemouth, a structural alteration typically costs £4,500–£9,750 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Can the beam be hidden?
Often, by setting it within the ceiling depth. It depends on the joists and span.
Do I need building regulations approval?
Yes. Removing a load-bearing wall is building work that needs approval, with calculations for the beam.
