Steel BeamInstallers
Victorian house mid-conversion into flats with new steel beams and stud walls

Flat & HMO conversion steels · Caerphilly

Flat & HMO conversion steels in Caerphilly

Survey, engineer's design and installation of flat & HMO conversion steels anywhere in Caerphilly.

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

Free survey in Caerphilly

Tell us about your flat & HMO conversion steels project in Caerphilly.

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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 flat & HMO conversion steels service in Caerphilly

Flat and HMO conversion steels are the beams, columns and frames needed when a house or building is reworked into self-contained flats or a house in multiple occupation. New layouts move walls, stairs and bathrooms, so steel picks up the loads that old walls used to carry, designed to work alongside the fire separation and sound insulation the conversion also needs.

We carry out flat & HMO conversion steels throughout Caerphilly, for homeowners, landlords and builders who need the structural part done properly. Coverage takes in Risca, Blackwood and Gelligaer and everywhere in between. You get an itemised written quote that shows the calculations, approvals, steel, labour and finishing as separate lines.

Key points for your project

  • Converting a house into flats is treated as a material change of use for building regulations purposes, so fire safety, sound insulation and other requirements apply across the building, not just to the structural work. The steelwork forms one part of that wider approval.
  • In a conversion, walls that carried load are often taken out to form open kitchens or wider corridors, while new partitions go in elsewhere. Each change is checked, because a new stud wall standing on old joists can add load the floor was never designed for.
  • The engineer looks at the whole building rather than one opening at a time. Loads from upper floors, new bathrooms and water storage are traced down to the foundations, and steel is placed so it suits the new layout without awkward downstands in habitable rooms.
  • A conversion to flats or an HMO may need planning permission for the change of use, depending on the scheme, its size and any local restrictions. Checking the planning position before design work begins avoids redesigning the layout and its steel later.
  • Large Victorian and Edwardian houses are popular for conversion, but they bring timber lintels, chimney breasts, lime mortar and joists notched for old services. These are uncovered early so the engineer can account for them before any steel is ordered.

Four stages, one team

  1. Survey in Caerphilly

    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 Caerphilly County Borough 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.

How much should I budget in Caerphilly?

As a guide, budget £2,300–£8,200 including VAT for steelwork for a flat or HMO conversion in Caerphilly, based on published UK cost guides adjusted for prices in Wales (-9%).

JobTypical guide rangeWhat it usually covers
Steelwork for a flat or HMO conversion£2,300–£8,200Beams and posts for a revised layout, with approvals; fire and sound separation priced with the conversion
Fire protection to a steel beam£140–£550 per beamFire-rated board boxing or an intumescent coating system as specified
Loft conversion steels£2,300–£5,450Supply and fit of floor and ridge steels on padstones, including lifting into the roof space
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 Wales (-9%) and are rounded. How these figures are worked out.

Building control and neighbours in Caerphilly

Welsh building regulations treat beams and new openings as controlled building work. We apply to Caerphilly County Borough Council on your behalf before anything is removed, give the commencement notice the 2026 Welsh rules require, and the steel is checked before it is boxed in.

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

Flat & HMO conversion steels by town

Questions about flat & HMO conversion steels in Caerphilly

Do I need a party wall agreement for flat & HMO conversion steels in Caerphilly?

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.

How much do flat & HMO conversion steels cost in Caerphilly?

As a guide, budget £2,300–£8,200 including VAT for steelwork for a flat or HMO conversion in Caerphilly, based on published UK cost guides adjusted for prices in Wales (-9%). The exact figure depends on the span, what the wall carries, access and the finish, and is fixed in writing once the scope is agreed.

What steel beams are needed for a flat conversion?

It depends on how much the layout changes. Typical steelwork includes beams where load-bearing walls are removed, trimmers around new stair openings, and columns or frames where loads have to come down through the building. A structural engineer designs each element from the new layout and the existing structure, and the calculations go to building control.

Does 5% VAT apply to a flat conversion?

It may. A reduced rate of VAT can apply to some conversion work, such as changing the number of dwellings in a building or converting a house into an HMO, provided the conditions are met. The rules have detail and exceptions, so confirm the position with your accountant before pricing the project on that basis.

Do I need an HMO licence before converting a house?

Possibly. Many HMOs need a licence from the local council, and some areas license smaller HMOs too. Licensing covers room sizes, amenities and fire safety, and it is separate from planning and building regulations. Check the council's requirements early, as they can affect the layout and therefore the steelwork needed.

Do I need planning permission to convert a house into an HMO?

You may, depending on the size of the HMO, where it is and any local restrictions. In some areas smaller HMOs can be formed without a planning application, while larger ones, and conversions into self-contained flats, usually need permission. Check with the local planning authority before committing to a layout and its steelwork.

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.