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

Rear extension steels · Helensburgh

Rear extension steels in Helensburgh

Rear extension steels in Helensburgh, from free survey to completion certificate.

  • Itemised written quote
  • Beam sized by a structural engineer
  • Covering Helensburgh and nearby

Free survey in Helensburgh

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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

About our rear extension steels service in Helensburgh

If you live in Helensburgh, rear extension steels can usually be planned and priced after a single survey visit. Our coverage runs across Argyll and Bute, so nearby villages are included too. We cover G84, and we fix the price in writing once the layout and scope are agreed.

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.

What to expect

  • Columns carry concentrated loads, so each normally sits on a pad foundation designed by the engineer. Digging these inside an existing kitchen or through a solid concrete floor takes planning, especially where drains run close to the back wall.
  • The building standards 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.
  • A single beam works where solid masonry is left at both ends of the opening. Where the opening runs nearly the full width or the corners are weak, the engineer may use columns or a goalpost frame, which is two posts and a beam bolted together.
  • The original rear wall of most houses is load-bearing because it supports first-floor joists and the bedroom wall above. Even where the joists run parallel to it, the masonry overhead still needs carrying, so steel is almost always part of opening it up.
  • The opening is usually formed once the extension walls and roof are up, so the house stays secure and dry. Leaving it too late can hold up plastering and floor screeding, so the steel date is agreed with the builder early on.

What happens, step by step

  1. Free visit

    A short visit to Helensburgh to see the job, agree what you want and check the bearings, floors and services that affect the design.

  2. Calculations

    The engineer's calculations and a simple drawing are prepared for your opening and shared with you before anything is ordered.

  3. Building warrant

    A building warrant is applied for from Argyll and Bute Council, and work starts only once the warrant has been granted.

  4. Steel in, made good

    On site we prop, open up, fit and pack the steel, then fire protect, box in and plaster once the inspection is done.

What do rear extension steels cost in Helensburgh?

As a guide, budget £2,300–£6,350 including VAT for opening into a rear extension in Helensburgh, based on published UK cost guides adjusted for prices in Scotland (-9%).

JobTypical guide rangeWhat it usually covers
Opening into a rear extension£2,300–£6,350Original rear wall removed with a beam or goalpost, approvals and propping, coordinated with the extension build
Structural calculations for a beam£230–£680Site measure or photos, beam and padstone design and calculations for building standards
Rear wall opening for bi-fold or sliding doors£2,300–£6,350External wall opened up to about 5 m with steel, propping, cavity tray and making good (doors supplied separately)
Steel column or post£460–£1,360 per columnColumn supplied and fitted with base and cap plates on a pad foundation

Figures include our approximate regional adjustment for prices in Scotland (-9%) and are rounded. How these figures are worked out.

Building control and neighbours in Helensburgh

Steel beam work in Helensburgh needs a building warrant from Argyll and Bute Council. The structural design is part of the application, and the council's building standards team accepts the completion certificate once the work is done as approved.

Scotland has no Party Wall Act. Work affecting a shared wall is governed by your title deeds and the general law, and in flats by the Tenements (Scotland) Act 2004, so it is sensible to agree the work with neighbours in writing before starting.

Building rules in Scotland

Rear extension steels near Helensburgh

Questions about rear extension steels in Helensburgh

Do you also work near Helensburgh?

Yes. We also cover nearby towns including Dunoon.

Do I need a party wall agreement for rear extension steels in Helensburgh?

There is no Party Wall Act in Scotland. Your title deeds and the general law apply instead, and the Tenements (Scotland) Act 2004 for flats, so agree the work with your neighbour in writing before it starts.

Is the steel included in the extension's building regulations?

Yes. The steelwork is part of the extension, so the engineer's calculations go to building standards with the extension application and the steel is inspected before it is covered. The completion certificate issued for the extension then covers the structural work to the rear wall.

Can I have a flat ceiling between the house and the extension?

Often, yes, but it depends on the floor depth above and the loads involved. The steel can sometimes be set up into the floor zone so the ceiling runs through level, which usually means more work to the joists. This needs deciding before the engineer designs the steel.

How wide can a rear extension opening be?

There is no fixed limit, and openings across the full width of a house are common with the right steel. The engineer sizes the beam or frame for the span and the loads above. Wider spans need deeper or heavier steel and possibly columns, which affects headroom and cost.

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.