Steel BeamInstallers
Garage conversion with the old door opening being bricked up around a new window

Garage conversion openings · Brecon

Garage conversion openings in Brecon

Steelwork, approvals and making good for garage conversion openings in Brecon and nearby.

  • Free survey visit in Brecon
  • Engineer's calculations arranged
  • Building control handled for you

Free survey in Brecon

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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 garage conversion openings service in Brecon

Planning garage conversion openings in Brecon? Our team covers LD3 and the streets around them. We also cover the surrounding towns and villages in Powys. You get one written quote for the calculations, approvals, propping, steel and making good.

Converting a garage is a popular way to add a room without extending. Structurally, two things usually happen: the big garage door opening is filled in with a wall, window or door on proper foundations, and a doorway or wider opening is formed through the wall between the garage and the house.

What to expect

  • The beam or lintel over a garage door was designed to span an open gap. It may be timber, concrete or steel, and in older houses it can be undersized or corroded, so the engineer checks it before anything is built underneath or above it.
  • Forming a doorway from the house into the converted garage often goes through a load-bearing wall, especially the original external wall of the house where the garage is attached. That opening needs a lintel or beam designed by the engineer.
  • An integral garage is usually separated from the house by fire-resisting construction. If part of it stays as a garage or store, that separation must be kept, and any new door between garage and house normally needs to be a fire door.
  • An infill wall needs a proper foundation. Garage floors are often a thin slab with no footing under the door line, so a new trench footing is usually dug across the opening to a depth and width the engineer and building control agree.
  • With an integral garage, the room above usually has its front wall sitting on the beam over the garage door. Any sag or rust in that beam matters more because it carries a wall and floor, and replacing it means propping the upstairs while new steel goes in.

What happens, step by step

  1. Survey in Brecon

    We visit, look at the wall and what sits above it, measure the opening and note services, access and how the steel can be brought in.

  2. Engineer's design

    A structural engineer sizes the beam, padstones and any posts, and sets out the temporary support needed while the wall is out.

  3. Building control

    We submit the application or notice to Powys County Council under the Building Regulations as they apply in Wales, before work starts.

  4. Install and sign-off

    Props go in, the opening is formed, the steel is set and packed, building control inspects it, and we make good.

What do garage conversion openings cost in Brecon?

As a guide, budget £910–£2,730 including VAT for garage door opening infill (structural part) in Brecon, based on published UK cost guides adjusted for prices in Wales (-9%).

JobTypical guide rangeWhat it usually covers
Garage door opening infill (structural part)£910–£2,730Beam or lintel checked or replaced, foundation and infill wall for the old door opening (window and finishes extra)
RSJ supply and fit (single beam)£730–£2,280 per beamBeam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately)
Lintel replacement£360–£1,090 per lintelPropping, removing the old lintel, new lintel set on beds and brickwork made good
Widening an internal doorway£910–£2,280Opening widened with a new lintel or short beam, approval where structural, and making good

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

Approvals in Brecon

In Wales, structural alterations come under the Building Regulations 2010 as they apply in Wales. Powys County Council handles building control for Brecon. For work started or approved from 1 July 2026, the Welsh system uses an application to building control, dutyholders appointed in writing, a commencement notice before work starts and a compliance statement at the end.

Where the steel bears into a wall shared with next door, notice must be served under the Party Wall etc. Act 1996. If your neighbour dissents, surveyors agree how the work is done before it starts.

Building rules in Wales

Garage conversion openings near Brecon

Questions about garage conversion openings in Brecon

Do I need a party wall agreement for garage conversion openings in Brecon?

Yes, if the beam bears into a shared wall: the Party Wall etc. Act 1996 applies in England and Wales, and a party structure notice must be served at least two months before that work starts. We arrange it through a party wall surveyor.

Can you work on older or listed homes in Brecon?

Yes. Older homes often have lime mortar, timber lintels or shallow footings, which the engineer allows for. Listed buildings need listed building consent for internal structural changes as well as building regulations approval, and that must be in place first.

How long do the structural works for a garage conversion take?

Typically one to two weeks for the structural stage: digging and concreting the infill foundation, building the infill wall, and forming any new opening into the house. Building control inspections fit around these stages, and the insulation, electrics, plastering and flooring of the conversion follow on afterwards.

Do I need a steel beam for a garage conversion?

Not always. If the existing beam over the garage door is sound and the infill wall sits on its own foundation, new steel may not be needed. Steel is usually required when forming an opening through a load-bearing wall into the house, or when the garage door beam is undersized or corroded. The engineer decides.

Does the infill wall need foundations?

Yes. A new masonry wall across the garage door opening needs a proper footing, as the existing garage slab is usually not designed to carry it. A trench is dug across the opening and a foundation is formed to the engineer's and building control's requirements, then inspected before the wall is built.

Do you cover Brecon for garage conversion openings?

Yes. We carry out garage conversion openings in Brecon and the LD3 postcode districts. Book a free survey visit and we will check the wall, arrange the engineer's calculations and send an itemised written quote.

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.