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

Bi-fold & sliding door openings · Farnborough

Bi-fold & sliding door openings in Farnborough

Bi-fold & sliding door openings in Farnborough, from free survey to completion certificate.

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

Free survey in Farnborough

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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 bi-fold & sliding door openings service in Farnborough

Bi-fold & sliding door openings in Farnborough are planned around the house, not a standard kit. Farnborough is around 8.7 miles from Woking, and we cover both. We visit, measure and check what the wall carries, then arrange calculations and building control approval before any steel is ordered.

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

  • Door suppliers quote a structural opening size, which allows for the frame and fixing tolerances. Agreeing that size before the steel is designed avoids reveals that are too tight or gaps that have to be packed out later.
  • A wide glazed opening changes the security of the back of the house. During the works the opening is boarded at night if the doors are not yet fitted, and it is worth checking the locking and glass specification of the doors you choose.
  • 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.
  • 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.
  • 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.

What happens, step by step

  1. Survey in Farnborough

    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 a building notice or full plans application to the local council's building control team, so approval is in place before the wall is touched.

  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.

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

As a guide, budget £2,800–£7,850 including VAT for rear wall opening for bi-fold or sliding doors in Farnborough, based on published UK cost guides adjusted for prices in the South East (+12%).

JobTypical guide rangeWhat it usually covers
Rear wall opening for bi-fold or sliding doors£2,800–£7,850External wall opened up to about 5 m with steel, propping, cavity tray and making good (doors supplied separately)
Lintel replacement£450–£1,340 per lintelPropping, removing the old lintel, new lintel set on beds and brickwork made good
RSJ supply and fit (single beam)£900–£2,800 per beamBeam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately)
Structural calculations for a beam£280–£840Site measure or photos, beam and padstone design and calculations for building control

Figures include our approximate regional adjustment for prices in the South East (+12%) and are rounded. How these figures are worked out.

Building control and neighbours in Farnborough

For Farnborough, building control is provided by the local council's building control team, or by a registered building control approver if preferred. We send them the engineer's calculations with a building notice or full plans application and book the inspections. Work done without approval can cause problems at sale and is far dearer to put right later.

If the beam bears into a wall you share with a neighbour, the Party Wall etc. Act 1996 applies, and a party structure notice must be served at least two months before that work starts. We arrange this through a party wall surveyor.

Building rules in England

Bi-fold & sliding door openings near Farnborough

Bi-fold & sliding door openings in Farnborough: your questions

Do you also work near Farnborough?

Yes. We also cover nearby towns including Camberley, Aldershot, Fleet and Sandhurst.

Can you work on older or listed homes in Farnborough?

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.

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.

Can I have a level threshold with bi-fold doors?

Often yes, but it has to be designed. The inside floor, outside paving and drainage all need to work together so water cannot run in, usually with a drainage channel outside and the right damp-proof detail under the door frame. We look at levels at the survey and plan the threshold with the door supplier.

How long does it take to make an opening for bi-fold doors?

The structural opening usually takes three to five working days, including propping, cutting out the wall, fitting the steel and outer leaf support, and forming the reveals. The doors can then be fitted, with inside making good and outside brickwork finishing following on. Lead times on made-to-order doors affect the overall timeline more than the 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.