Steel BeamInstallers
Rear wall opened for wide doors with a galvanised steel beam and props, garden beyond

Bi-fold & sliding door openings · Haverfordwest

Bi-fold & sliding door openings in Haverfordwest

Steelwork, approvals and making good for bi-fold & sliding door openings in Haverfordwest and nearby.

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

Free survey in Haverfordwest

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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

What bi-fold & sliding door openings involve in Haverfordwest

We cover bi-fold & sliding door openings in Haverfordwest (SA61) and the streets around it. Our coverage runs across Pembrokeshire, so nearby villages are included too. Each job is designed by a structural engineer and approved through Pembrokeshire County Council before work begins.

We coordinate the structure with your door supplier's sizes, so the finished opening matches the frame. The survey visit, structural calculations from a qualified engineer, building control, propping, steel, cavity trays, weather protection while the wall is open and making good are all covered in one itemised written quote.

Things to plan for

  • Very wide openings, or ones that run close to the corner of the house, may leave too little wall for the beam to bear on. In that case the engineer may specify steel columns or a goalpost frame standing on its own foundations.
  • External walls can have gas meters, boiler flues, soil pipes, outside taps or cables near the new opening. These are found at survey and moved by the right trade, with any gas pipework done by a Gas Safe registered engineer as the law requires.
  • Level or flush thresholds are popular with bi-fold doors, but the floor inside and the patio outside need planning together. Drainage at the threshold and a proper damp-proof detail stop water running in when the outside is close to floor level.
  • The house is open to the weather between taking out the wall and fitting the doors. Temporary sheeting or a boarded frame keeps rain out and the house secure, so the gap between the structural work and door fitting should be kept short.
  • New glazed doors must meet the energy efficiency requirements of the building regulations, and a wide opening adds a large area of glazing to the house. The door supplier normally provides the performance data that building control needs.

How the job runs in Haverfordwest

  1. Free visit

    A short visit to Haverfordwest 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 control

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

  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.

Guide prices for bi-fold & sliding door openings in Haverfordwest

As a guide, budget £2,300–£6,350 including VAT for rear wall opening for bi-fold or sliding doors in Haverfordwest, based on published UK cost guides adjusted for prices in Wales (-9%).

JobTypical guide rangeWhat it usually covers
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 goalpost frame£1,800–£5,450Two posts and a beam bolted as a frame, pad foundations, base plates and fitting
Widening an internal doorway£910–£2,280Opening widened with a new lintel or short beam, approval where structural, and making good
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

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 Haverfordwest

In Wales, structural alterations come under the Building Regulations 2010 as they apply in Wales. Pembrokeshire County Council handles building control for Haverfordwest. 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.

The Party Wall etc. Act 1996 applies in Wales as well as England, so a beam bearing into a shared wall needs a party structure notice at least two months before work starts. We arrange notices through a party wall surveyor.

Building rules in Wales

Bi-fold & sliding door openings near Haverfordwest

Questions about bi-fold & sliding door openings in Haverfordwest

Can I stay at home while the work is done in Haverfordwest?

Usually, yes. The work area is screened and floors are protected. The rooms either side of the opening are out of action for a few days, and there is some noise and dust while the masonry comes out.

Do you also work near Haverfordwest?

Yes. We also cover nearby towns including Milford Haven, Pembroke Dock, Pembroke and Tenby.

Do I need planning permission for bi-fold doors?

Usually not for a rear opening in a house, as this generally falls within permitted development. Planning or another consent may be needed for front elevations, flats, listed buildings, conservation areas with extra controls, or homes where permitted development rights have been removed. We flag this at survey so you can check before work is booked.

Should I order my doors before the opening is made?

It helps to choose them first. The supplier's structural opening size and threshold detail feed into the steel design, so the opening is formed to suit the doors exactly. Many people order once the engineer has confirmed the opening, then time the structural work so the gap is weathered for as short a time as possible.

Will the house be open to the weather while the wall is out?

Only briefly, and it is protected throughout. Once the wall is out, the opening is sheeted or boarded so it stays weathertight and secure until the doors arrive. Timing the structural work close to the door delivery date keeps that period as short as possible.

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.