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East SussexStructural alterations and knock-throughs

Structural alterations and knock-throughs in Brighton

SK Developments builds structural alterations in Brighton. We look after the design, the planning or permitted development check, building control and the build itself.

Guide price in Brighton

£5,000–£10,500 for a typical knock-through with steel beam

In Brighton, a structural alteration typically costs £5,000–£10,500 for a typical knock-through with steel beam, including VAT at 20% (standard rate).

Book a free home visit

Tell us about your project. We reply to arrange a visit and a fixed quote.

Free home visit and measured survey
Fixed price for the agreed specification
Drawings, approvals and build in one contract
Building control sign-off arranged
England, Wales, Scotland and Northern Ireland

What is a structural alteration?

Steel beam installed across a wide opening with props in place during a knock-through

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 Brighton?

In Brighton, 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 Brighton are adjusted to reflect that. Design, structural calculations and council fees are extra.

Guide prices for Brighton, including VAT at 20% (standard rate)
Size or typeGuide range
A typical knock-through with steel beam£5,000–£10,500
Higher specification£10,500–£13,000

Your quote will depend mainly on:

  • Flush or downstand beam
  • Moving radiators, sockets and pipes
  • What sits above the wall
  • Span of the opening

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 Brighton?

Approvals for a structural alteration in Brighton 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.

At the survey we check your house’s planning history and any restrictions, and tell you which route applies.

What we handle

The work we manage on a structural alteration:

  • Structural engineer’s calculations and drawings
  • Steel beam supply and installation on padstones
  • Building control application
  • Party wall notices where needed
  • Temporary propping
  • Fire protection to the steel

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 Brighton

Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.

We work across Brighton and neighbouring areas such as Hove, Portslade and Rottingdean. Postcodes we cover in Brighton include BN2.

How it works

  1. 01

    Free visit

    We look at the property, talk through what you want and measure up. There is no charge and no obligation.

  2. 02

    Design and pricing

    Design options, then a fixed quote based on the chosen drawings and specification.

  3. 03

    Approvals in place

    We handle planning, building control and neighbour notices before work starts.

  4. 04

    Build and sign-off

    We run the build to a written programme and hand over the completion certificate.

Questions about structural alterations in Brighton

How long does a structural alteration take in Brighton?

Typically 1 to 2 weeks on site for a typical knock-through. Design and approvals beforehand usually take 6 to 12 weeks.

What fire protection does a steel need?

Usually fire-rated plasterboard or intumescent paint, as building control requires.

Can the beam be hidden?

Often, by setting it within the ceiling depth. It depends on the joists and span.

How much does a structural alteration cost in Brighton?

In Brighton, 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.

Do I need a party wall notice?

In England and Wales, if the beam sits in a party wall, yes.

Ready to talk about a structural alteration in Brighton? Book a free home visit or get an instant guide price.

Call 0800 088 6248 or get an instant guide price online.

Call 0800 088 6248Get a guide price