Steel BeamInstallers
Rear extension under construction with a steel beam over the opening into the house

Rear extension steels · Prestwich

Rear extension steels in Prestwich

Rear extension steels for homes in M25, M26, M45, designed by a structural engineer.

  • Price fixed in writing once scope is agreed
  • Building control arranged
  • Temporary works and making good included

Free survey in Prestwich

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  • Free survey visit
  • Engineer's calculations arranged
  • Building control handled
  • Fixed written price once scope is agreed
  • England, Wales, mainland Scotland & NI

Rear extension steels in Prestwich: how it works

Planning rear extension steels in Prestwich? Our team covers M25, M26 and M45 and the streets around them. It sits about 3.2 miles from Salford, which we also cover. You get one written quote for the calculations, approvals, propping, steel and making good.

Building a rear extension is only half of the open-plan result. The original back wall still holds up the first floor and the rear wall of the bedrooms above, so opening it needs steel. Depending on the width and what is left to bear on, that could be a single beam on padstones, a beam on columns, or a full goalpost frame.

Worth knowing before you start

  • The steelwork forms part of the extension's building regulations approval, and the engineer's calculations go in with it. Planning for the extension itself is separate; many rear extensions to houses in England fall within permitted development, subject to size limits and conditions.
  • When bi-fold or sliding doors sit directly beneath the new steel, the beam has to stay stiff enough not to bind the door panels. The engineer sets a tighter deflection limit, which can mean a deeper or heavier section than strength alone would need.
  • Two-storey rear extensions add a second level of loads to think about. Steels at first-floor level may carry the existing rear wall of the bedrooms or tie the new roof into the old one, so the engineer looks at both floors together.
  • Opening the rear wall is usually the dustiest stage of an extension project. The work face is sheeted off from the rest of the house, and the kitchen is often out of use for a few days while the opening is formed and the steel goes in.
  • The building control completion certificate for the extension covers the steelwork to the old rear wall. Keep it with the engineer's calculations and drawings, as a buyer's solicitor will expect to see the structural paperwork for the extension.

From survey to sign-off in Prestwich

  1. Look and measure

    We check the wall, the span you want and what the wall is carrying, and photograph anything the engineer needs to see.

  2. Design and price

    Calculations come back from the engineer and we confirm your fixed written price, line by line.

  3. Building control

    We submit a building notice or full plans application to Bury Council, so approval is in place before the wall is touched.

  4. Fit, inspect, finish

    The work is propped and the steel installed and packed tight. After inspection the opening is boxed, plastered and left clean.

Guide prices for rear extension steels in Prestwich

As a guide, budget £2,400–£6,700 including VAT for opening into a rear extension in Prestwich, based on published UK cost guides adjusted for prices in the North West (-4%).

JobTypical guide rangeWhat it usually covers
Opening into a rear extension£2,400–£6,700Original rear wall removed with a beam or goalpost, approvals and propping, coordinated with the extension build
Party wall surveyor (agreed surveyor, per neighbour)£860–£1,920 per neighbourSchedule of condition and award where a neighbour dissents; serving notice alone, where the neighbour consents, costs far less (England and Wales only)
Structural calculations for a beam£240–£720Site measure or photos, beam and padstone design and calculations for building control
Steel goalpost frame£1,900–£5,750Two posts and a beam bolted as a frame, pad foundations, base plates and fitting

Figures include our approximate regional adjustment for prices in the North West (-4%) and are rounded. How these figures are worked out.

Approvals in Prestwich

In England, taking out a load-bearing wall or putting in a beam is building work under the Building Regulations 2010. It needs approval from building control, either Bury Council or a registered building control approver, through a full plans application or a building notice. Part A covers the structure and Part B covers fire safety, which is why steel in homes is usually fire protected.

Terraced and semi-detached homes often need party wall notices, because cutting into a shared wall to take a beam end is notifiable under the Party Wall etc. Act 1996. Allow at least two months for the notice period unless your neighbour agrees sooner.

Building rules in England

Rear extension steels near Prestwich

Questions about rear extension steels in Prestwich

What happens at the survey visit in Prestwich?

We look at the wall, the floor and ceiling either side and what sits above, measure the opening you want, and note cables, pipes and access for the steel. It usually takes under an hour and there is no charge.

How soon can rear extension steels start in Prestwich?

Start dates depend on the engineer's calculations, the building control approval and, where needed, party wall notice periods. We give you a realistic timetable after the survey and keep you updated as each approval comes through.

Do I need a steel beam for my rear extension?

If the original back wall is being opened up into the extension, almost certainly yes. That wall normally carries the first floor and the wall above, so a beam, columns or a goalpost frame takes over the job. A structural engineer confirms exactly what is needed once the opening width and loads are known.

Do I need a party wall agreement for extension steels?

In England and Wales, if a beam bears into a wall shared with a neighbour, or the extension foundations are dug close to theirs, notice under the Party Wall etc. Act 1996 is usually required. We can arrange the notices through a party wall surveyor. There is no equivalent legislation in Scotland or Northern Ireland.

Who designs the steels for a rear extension?

A structural engineer. Your architect's drawings show the layout, but the engineer calculates the beams, columns, connections and foundations. We arrange those calculations, or work from an engineer's design you already have, and make sure the details suit the builder's programme.

Planning to take a wall out?

Book a free survey visit. You get an itemised written quote covering calculations, building control, steel and making good.