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 Teddington?
In Teddington, a structural alteration typically costs £5,750–£12,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Building costs in London run about 30% above the UK average, and the figures for Teddington 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 | £5,750–£12,500 |
| Higher specification | £12,500–£15,500 |
What moves the price most:
- Moving radiators, sockets and pipes
- Party wall involvement
- Span of the opening
- Floor and ceiling repairs
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 Teddington?
Before anything is built in Teddington, 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.
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
Handled as part of most structural alterations:
- Temporary propping
- Making good, plastering and flooring repairs
- Party wall notices where needed
- Structural engineer’s calculations and drawings
- Building control sign-off
- Building control application
How long does it take?
The build itself usually takes 1 to 2 weeks on site for a typical knock-through. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in Teddington
Victorian and Edwardian terraces dominate many London streets, which is why side return, wraparound and mansard projects are so common here.
If your home is in Teddington or close by in Kingston upon Thames, Twickenham and East Molesey, 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 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
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about structural alterations in Teddington
How long does a structural alteration take in Teddington?
Typically 1 to 2 weeks on site for a typical knock-through. Design and approvals beforehand usually take 6 to 12 weeks.
Do I need building regulations approval?
Yes. Removing a load-bearing wall is building work that needs approval, with calculations for the beam.
What fire protection does a steel need?
Usually fire-rated plasterboard or intumescent paint, as building control requires.
Do I need a party wall notice?
In England and Wales, if the beam sits in a party wall, yes.
How much does a structural alteration cost in Teddington?
In Teddington, 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.
