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

Bi-fold & sliding door openings · Catford

Bi-fold & sliding door openings in Catford

Bi-fold & sliding door openings for homes in SE4, SE6, SE12, designed by a structural engineer.

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

Free survey in Catford

Tell us about the bi-fold & sliding door opening job in Catford.

Please enter your name.
Please enter a UK phone number.
Please enter a valid email.
Please enter a UK postcode.
Please tell us a little about the job.
  • 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 Catford

Catford has a mix of housing, and bi-fold & sliding door openings need a slightly different approach in each. The wider London area is covered as well. Whatever the age of the property, the steel goes in on proper bearings with temporary support in place throughout.

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

  • 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.
  • 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.
  • 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.
  • Width, what sits above, whether columns or a goalpost are needed, outer leaf support, threshold works and how much brickwork needs matching all affect the price. The doors themselves are normally supplied separately unless agreed otherwise.

How the job runs in Catford

  1. Look and measure

    We check the wall, the span you want and what the wall is carrying, and photograph anything the engineer needs to see.

  2. Design and price

    Calculations come back from the engineer and we confirm your fixed written price, line by line.

  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. Fit, inspect, finish

    The work is propped and the steel installed and packed tight. After inspection the opening is boxed, plastered and left clean.

How much should I budget in Catford?

As a guide, budget £3,200–£8,950 including VAT for rear wall opening for bi-fold or sliding doors in Catford, based on published UK cost guides adjusted for London prices (+28%).

JobTypical guide rangeWhat it usually covers
Rear wall opening for bi-fold or sliding doors£3,200–£8,950External wall opened up to about 5 m with steel, propping, cavity tray and making good (doors supplied separately)
Structural calculations for a beam£320–£960Site measure or photos, beam and padstone design and calculations for building control
Opening into a rear extension£3,200–£8,950Original rear wall removed with a beam or goalpost, approvals and propping, coordinated with the extension build
Steel goalpost frame£2,550–£7,700Two posts and a beam bolted as a frame, pad foundations, base plates and fitting

Figures include our approximate regional adjustment for London prices (+28%) and are rounded. How these figures are worked out.

Building rules for Catford

In England, taking out a load-bearing wall or putting in a beam is building work under the Building Regulations 2010. It needs approval from building control, either the local council's building control team or a registered building control approver, through a full plans application or a building notice. Part A covers the structure and Part B covers fire safety, which is why steel in homes is usually fire protected.

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 Catford

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

What happens at the survey visit in Catford?

We look at the wall, the floor and ceiling either side and what sits above, measure the opening you want, and note cables, pipes and access for the steel. It usually takes under an hour and there is no charge.

Do you also work near Catford?

Yes. We also cover nearby towns including Blackheath, Greenwich, Beckenham and Peckham.

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.

Why does the beam need to be stiffer for glazed doors?

Because glazed doors tolerate very little movement. Every beam bends slightly under load, and with bi-folds or sliders that movement can make panels bind, tracks drag or glass crack. The engineer sets a stricter deflection limit for these openings, which often means a heavier section than strength alone would need.

How wide can a bi-fold door opening be?

There is no fixed limit, as it depends on the loads above and what the beam can bear on. The engineer designs the steel and, for very wide openings or ones near a corner, may specify columns or a goalpost frame. The door system's own maximum panel sizes and configurations also need checking.

Do you cover Catford for bi-fold & sliding door openings?

Yes. We carry out bi-fold & sliding door openings in Catford and the SE4, SE6, SE12, SE13 and SE14 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.