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DorsetStructural alterations and knock-throughs

Structural alterations and knock-throughs in Christchurch

SK Developments designs, gets approval for and builds structural alterations in Christchurch and across Dorset, with one contract from the first drawing to the building control sign-off.

Guide price in Christchurch

£4,500–£9,750 for a typical knock-through with steel beam

In Christchurch, a structural alteration typically costs £4,500–£9,750 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 Christchurch?

In Christchurch, 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 Christchurch reflects that. Design, structural calculations and council fees are extra.

Guide prices for Christchurch, including VAT at 20% (standard rate)
Size or typeGuide range
A typical knock-through with steel beam£4,500–£9,750
Higher specification£9,750–£12,000

The biggest cost drivers are:

  • Span of the opening
  • Party wall involvement
  • Flush or downstand beam
  • 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 Christchurch?

Before anything is built in Christchurch, 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.

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:

  • Temporary propping
  • Structural engineer’s calculations and drawings
  • Building control application
  • Steel beam supply and installation on padstones
  • Building control sign-off
  • Party wall notices where needed

How long does it take?

Expect 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 Christchurch

The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.

Projects in Christchurch (BH23) are surveyed in person before we quote, so the price reflects your actual property.

How it works

  1. 01

    Survey and brief

    We visit, discuss your ideas and budget, and survey the property or site at no cost.

  2. 02

    Design and pricing

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

  3. 03

    Permissions sorted

    Applications, building control and neighbour arrangements, all before the start date.

  4. 04

    Construction and completion

    We build, put right any snags and hand over the building control certificate.

Questions about structural alterations in Christchurch

How much does a structural alteration cost in Christchurch?

In Christchurch, 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.

Do I need a party wall notice?

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

Do you build structural alterations in Christchurch?

Yes. We build structural alterations across Christchurch, including postcodes BH23. Every project starts with a free home visit.

What fire protection does a steel need?

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

How long does a knock-through take?

Usually 1 to 2 weeks on site, plus a few days for plastering to dry.

Get a free, no-obligation home visit for your structural alteration in Christchurch.

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

Call 0800 088 6248Get a guide price