How to choose between Schüco bifold doors suppliers

Here is the thing nobody selling you a door will lead with: the aluminium is not the variable. Schüco designs and extrudes the profiles and supplies them to fabricators. Whether your doors come from a firm in Cheshunt or a firm in Borehamwood, the extrusion is the same extrusion.

Which means the £4,000 spread between your cheapest and dearest quote is buying something other than metal. Usually it is buying some combination of glass specification, survey competence, fitting quality and the likelihood that anyone returns your call in year four. Those are worth paying for. They are also invisible on a quotation unless you go looking.

What "approved fabricator" actually means

Systems houses run partner or approved-fabricator schemes. Being on one generally means the company has been trained on the system, has the right machining equipment and buys directly rather than through a middleman. It is a meaningful signal, particularly for warranty claims later, because a direct fabricator can get technical support and replacement parts through a proper channel.

It is not a guarantee of good fitting. Fabrication and installation are different skills and are often different people. Plenty of excellent fabricators subcontract fitting; some of those subcontractors are superb and some are two lads and a van. Ask who is fitting, and whether they are employed or subcontracted. The answer does not have to be "employed", but the willingness to answer tells you something.

Six questions that sort the field quickly

1. Which system, exactly? Not "Schüco bifold" — the system code and profile depth. Anyone who cannot answer immediately is not fabricating your doors.
2. Who does the final survey, and when? The correct answer is: someone technical, after the structural opening exists and the beam is in. Surveys taken off a drawing are a gamble with your money.
3. What is the whole-door U-value, and what glass gives you that figure? A number without the glass spec attached is meaningless.
4. What deflection do you need in the beam above? If they have no view on this, they have not thought about your opening.
5. Who makes good the reveals, inside and out? The single most common gap between what a homeowner expects and what a quote includes.
6. Can I see one you fitted more than three years ago? New installations all look fine. A three-year-old one shows you the gaskets, the coating and whether the gear has held its adjustment.

Reading the quote itself

A quotation that consists of one line and one number is not a quotation, it is a hope. What you want to see, itemised:

• System name, profile depth and configuration, with a drawing of the leaf layout and the stacking direction
• Glass specification: unit make-up in millimetres, coating, gas fill, spacer type, and whether toughened or laminated
• Threshold type
• RAL number and finish, with dual-colour noted separately if applicable
• Hardware: handle, lock, cylinder standard
• Removal and disposal of the existing frame
• Making good, and to what standard — plaster-ready or decorated
• Scaffolding or access equipment if needed
• Guarantee terms, split between product and installation
• VAT, stated explicitly

Firms that publish their range and technical detail openly rather than hiding everything behind a lead-capture form tend to quote the same way. It is a reasonable proxy. 5EC Alu, for example, is one of the North London fabricators that puts profile and configuration information on the site rather than making you fill in a form to see it, which at least lets you check a quote against something.

Guarantees: read which half is which

There are almost always two. The product guarantee covers the doors themselves — typically ten years on the profile and coating, and often shorter on moving parts and sealed units. The installation guarantee covers the work, and this is where the range is enormous: we have seen anything from twelve months to ten years.

The awkward truth is that most problems in the first five years are installation problems, not product problems. A door that binds, drops, or lets water past the threshold is nearly always a fitting or a structural issue. A one-year installation guarantee on a ten-year product is a mismatch worth asking about.

Also check what happens if the company stops trading. Insurance-backed guarantees exist for exactly this reason and cost the installer very little. Ask whether yours is backed and by whom.

Deposits and stage payments

Twenty to thirty per cent on order is normal — these are made-to-measure goods and the fabricator is committing to materials. Anything approaching half up front deserves a hard look. Anything demanding the full amount before installation deserves a polite no.

Pay the deposit by credit card if the amount qualifies, because the additional statutory protection costs you nothing. Keep a final payment of at least ten per cent until after the doors have been snagged and you have used them for a week. Reputable installers expect this; it is not an insult.

The very cheap quote

If one price is thirty per cent below the others, something has been left out. Usually it is one of: the glass has dropped to a basic unit, making good is excluded, the threshold has changed, the survey will be done off a drawing, or VAT is missing. Occasionally the company genuinely has lower overheads and is a bargain. Find out which by asking them to itemise against the highest quote you have, line for line.

One last suggestion, and it costs nothing. If you are also replacing windows, price them at the same time and from the same firm. Not only for the discount — matching the coating batch across doors and aluminium windows ordered together avoids the slight but visible colour drift you get when the same RAL is coated two years apart.

Common questions