Bi-fold & sliding door openings · Milford Haven
Bi-fold & sliding door openings in Milford Haven
Steelwork, approvals and making good for bi-fold & sliding door openings in Milford Haven and nearby.
- Free survey visit in Milford Haven
- Engineer's calculations arranged
- Building control handled for you
- 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 Milford Haven
We carry out bi-fold & sliding door openings in Milford Haven, covering the SA73 postcode district. The wider Pembrokeshire area is covered as well. The job starts with a free survey visit so the engineer's calculations are based on your actual walls, floors and loads.
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.
Worth knowing before you start
- 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.
- Both leaves of a cavity wall need support over the opening. Depending on the design, the outer brickwork may sit on a plate fixed to the beam or on a separate external lintel, and the engineer specifies which suits the loads and the look.
- 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.
- 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.
From survey to sign-off in Milford Haven
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.
Design and price
Calculations come back from the engineer and we confirm your fixed written price, line by line.
Building control
We submit the application or notice to Pembrokeshire County Council under the Building Regulations as they apply in Wales, before work starts.
Fit, inspect, finish
The work is propped and the steel installed and packed tight. After inspection the opening is boxed, plastered and left clean.
Guide prices for bi-fold & sliding door openings in Milford Haven
As a guide, budget £2,300–£6,350 including VAT for rear wall opening for bi-fold or sliding doors in Milford Haven, based on published UK cost guides adjusted for prices in Wales (-9%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Rear wall opening for bi-fold or sliding doors | £2,300–£6,350 | External wall opened up to about 5 m with steel, propping, cavity tray and making good (doors supplied separately) |
| Opening into a rear extension | £2,300–£6,350 | Original rear wall removed with a beam or goalpost, approvals and propping, coordinated with the extension build |
| RSJ supply and fit (single beam) | £730–£2,280 per beam | Beam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately) |
| Lintel replacement | £360–£1,090 per lintel | Propping, removing the old lintel, new lintel set on beds and brickwork made good |
Figures include our approximate regional adjustment for prices in Wales (-9%) and are rounded. How these figures are worked out.
Approvals in Milford Haven
Welsh building regulations treat beams and new openings as controlled building work. We apply to Pembrokeshire County 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.
Bi-fold & sliding door openings near Milford Haven
- Pembroke Dock 4.4 mi
- Pembroke 6.0 mi
- Haverfordwest 6.8 mi
- Tenby 14.8 mi
Bi-fold & sliding door openings in Milford Haven: your questions
Do you also work near Milford Haven?
Yes. We also cover nearby towns including Pembroke Dock, Pembroke, Haverfordwest and Tenby.
Do I need a party wall agreement for bi-fold & sliding door openings in Milford Haven?
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.
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.
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.
Do I need a steel beam for bi-fold doors?
Usually, yes. Bi-fold and sliding doors need wide openings, and in a load-bearing external wall that span is normally carried on steel. The engineer designs it for strength and stiffness, because glazed doors can stick or be damaged if the beam deflects. A small opening under light loads might only need a lintel, but that is the engineer's call.
Can I stay at home while the work is done in Milford Haven?
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.