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 on the Isle of Wight?
In the Isle of Wight, a structural alteration typically costs £5,000–£10,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for the Isle of Wight 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 | £5,000–£10,500 |
| Higher specification | £10,500–£13,000 |
The main things that change the cost:
- Moving radiators, sockets and pipes
- Span of the opening
- 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 on the Isle of Wight?
Approvals for a structural alteration in the Isle of Wight 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.
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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
What we take care of:
- Steel beam supply and installation on padstones
- Building control application
- Building control sign-off
- Fire protection to the steel
- Temporary propping
- Party wall notices where needed
How long does it take?
Expect 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 on the Isle of Wight
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Towns we cover on the Isle of Wight include Newport, Ryde, Cowes and Sandown.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 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 on the Isle of Wight
How much does a structural alteration cost in the Isle of Wight?
In the Isle of Wight, 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.
Can the beam be hidden?
Often, by setting it within the ceiling depth. It depends on the joists and span.
Do you build structural alterations in the Isle of Wight?
Yes. We build structural alterations across the Isle of Wight, including postcodes PO30, PO31, PO32, PO33 and PO34. 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.
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.
