The short answer
A fitted bifold door in the UK typically costs between £2,500 and £9,000, with most three to four-pane installations into an existing opening landing around £3,500 to £6,500. That figure combines the made-to-measure door set, fitting labour of roughly £600 to £1,500, and sometimes additional building work. Installation alone is a fraction of the total; the bigger swing comes from whether you are simply replacing an existing door or enlarging an opening, which needs a structural lintel or steel beam, plus plastering and making good. Always confirm exactly what a fitted quote covers before comparing prices, because two quotes can describe very different scopes of work.
Installation labour is only part of a fitted bifold cost; structural and finishing work often sits alongside it and is easy to overlook.
Quick reference
- Fitting labour only£600–£1,500
- Fitted 3-pane (existing opening)£2,500–£5,000
- Fitted 4-pane£3,500–£6,500
- New steel beam (if widening)£1,500–£4,000+
What a fitted bifold cost includes
A fitted price brings together the door, the labour and, depending on the job, structural and finishing work. The table shows indicative UK 2026 figures for a like-for-like replacement into an existing opening, where no major structural change is needed.
In this scenario the bulk of the cost is the door set itself, with fitting labour the next largest line. Making good covers tidying the reveals, sill and internal plaster where the old door is removed. The total is predictable because the opening already exists and is supported by a lintel, so the work is mostly removal, fitting and finishing rather than building.
| Element | Typical cost | Notes |
|---|---|---|
| Door set (3-pane) | £1,500–£3,500 | Made-to-measure, aluminium |
| Fitting labour | £600–£1,500 | 1–2 fitters, 1–2 days |
| Making good / plastering | £200–£600 | Reveals and internal finish |
| Removal & disposal | £100–£300 | Old door taken away |
| Total fitted (typical) | £2,500–£5,000 | Existing opening |
Indicative UK figures for a like-for-like replacement; widening an opening adds structural cost.
When the opening needs structural work
If you are replacing a single door or window with a wide bifold, the wall opening usually has to be enlarged. That means a new structural lintel or steel beam designed to carry the load above. This is where costs climb steeply:
- Structural calculations from an engineer for the beam specification.
- Supply and fit of a steel beam or concrete lintel, often £1,500 to £4,000 or more depending on span.
- Building Regulations approval for the structural opening, separate from the door's own glazing compliance.
- Brickwork, plastering and floor making good around the new opening.
For an extension, the bifold opening is usually formed as part of the build, so the structural element sits in the builder's quote rather than the door installer's. Either way, the structural work can roughly double the cost compared with a simple same-size replacement, so it is worth deciding early whether a wider opening is worth it.
Comparing fitted quotes fairly
Because a fitted quote can mean very different scopes, compare like for like. Ask each installer whether the price includes the threshold type you want, removal and disposal of the old door, scaffolding if needed, structural work, and making good. A cheaper headline quote that excludes plastering or a lintel can end up dearer than a fuller one once the missing items are added.
Self-certified installations through a FENSA or equivalent scheme also save you a separate building control fee for the glazing, and give a registered installer's accountability for the work. Check the product warranty on the door and glass, the workmanship guarantee on the fitting, and whether VAT is included in the quoted figure, since these affect the true cost and the cover you get if something goes wrong later.
How long the work takes and how to budget
A straightforward replacement into an existing opening usually takes one to two days for a pair of fitters, while a job that involves forming or widening an opening, fitting a steel beam and making good can run to a week or more across the trades. Planning for the disruption matters, especially where the doors are the main access to a garden or where the room is in daily use.
When budgeting, treat the door set and the building work as two separate lines. Get the structural work specified and priced first if the opening is changing, then add the door supply and fit. Build in a contingency for unexpected findings once the old door or wall is opened up, such as a lintel that needs upgrading or floor levels that need adjusting for the new threshold. A clear, itemised quote that separates door, fitting, structure and making good is the easiest to budget against and to compare.
It also pays to think about timing and sequencing across the trades. Where an opening is being widened, the structural beam and brickwork usually come first, then plastering needs time to dry before the final finishes go on, and the door fit slots in once the opening is formed and the lintel signed off. Squeezing those stages together to save days can backfire if a wet plaster reveal is rushed or the threshold is set before the floor level is confirmed. A realistic schedule, agreed with the installer and any builder, keeps the job moving without compromising the finish, and avoids the extra cost of returning to put right work that was done out of order. For most homeowners, the dependable route is a single fitted quote that names the door, the labour, the structural element and the making good as separate lines, so the price and the programme are both clear before anyone starts.
Frequently asked questions
How long does it take to fit bifold doors?
A straightforward replacement into an existing opening usually takes one to two days for two fitters. Jobs involving a new opening, steel beam and making good can run to a week or more across the trades involved.
Do I need building regulations for bifold doors?
Replacement glazed doors must meet thermal and safety glazing standards, which a registered installer can self-certify through FENSA. Enlarging the opening is a structural change that needs separate building control approval.
Is installation cheaper if I supply the doors myself?
Buying supply-only and hiring a fitter can work if you already have a builder on site, but you take on responsibility for measurements and compliance. Many homeowners prefer a single fitted quote so one company is accountable.
What is usually excluded from a fitted quote?
Common exclusions are a new lintel or steel beam, structural calculations, significant plastering, scaffolding and floor levelling. Always ask what is not included so a low quote does not hide essential extra work.
Does a fitted quote include VAT?
Not always, so check. Some quotes show the figure before VAT, which adds twenty per cent. Confirming whether VAT is included makes comparison between installers accurate.
Sources & further reading
- Checkatrade — bifold door cost guide
- MyJobQuote — bifold door installation costs
- FENSA — replacement window and door rules
Figures on this page are typical UK ranges drawn from published sources and depend on your specific opening and material. They are guidance, not a quotation.