Custom-made windows and doors: how to order, step by step

Ordering custom-made windows for the first time can seem like an opaque process: you call, someone comes to “take measurements”, a quote arrives, and it isn’t always clear what happens next. Many people come to us with the same underlying question: “But how does it actually work, ordering new windows?”

In this article we lay out the entire order journey from the customer’s side, from first contact through to delivery on site. This isn’t a guide to installation or to measuring: here we talk about the order flow — what to decide, what to prepare and what to ask at each stage. The aim is to remove the anxiety of a “leap in the dark” and get you to the signature knowing exactly what you’re buying.

One premise that holds throughout the article: any timeframe, price or tolerance you read is an indicative order of magnitude, given as an example. The real figures depend on your specific case, the product and the time of year, and your supplier will always confirm them to you in writing.

The stages of an order, in summary

Before going into detail, here’s the full map of the journey. Every project is different, but the basic flow is almost always the same.

Stage	What happens	Who acts
1. First contact	You describe your needs, get a sense of the price bracket	You + supplier
2. Site visit and survey	The openings are measured on site	You or your installer
3. Product selection	Profile, glass, hardware, colours, opening types	You, guided by the supplier
4. Quote and specification	Detailed offer, item by item	The supplier
5. Order confirmation	You sign, pay the deposit, production begins	You
6. Production	The custom-made windows and doors are built	The manufacturer
7. Delivery (and installation)	They arrive on site and are fitted	Your installer

How LMT works in Italy. Here “supplier” means the generic role of whoever sells you the windows. In Italy LMT works on a supply-only basis: it produces and delivers the made-to-measure windows, while the survey and installation stay with the client’s trusted fitter. In a full-service model, by contrast, survey, supply and installation are in the same hands: this guide flags both cases where it matters.

The time between stages varies a great deal. The stages that really matter — where your decisions genuinely count — are 3 and 4: that’s where you define what you’re ordering. Let’s look at each one in turn.

Stage 1 — First contact: what to prepare

The first contact is used to frame the project and to see whether there’s a good fit. You don’t need to arrive as prepared as a technician, but the more information you provide, the more sensible the guidance you’ll receive.

Useful things to have in mind or on hand:

• How many windows and doors you want to replace, and in which rooms (the whole house? just the bedrooms?).
• Rough measurements, even approximate ones taken with a tape measure: these are only for orientation, not the actual survey.
• The problem you want to solve: draughts, cold, noise, condensation, appearance. This matters more than technicalities, because it guides the product selection.
• The context of the works: renovation, new build or a straightforward replacement? This changes things considerably.

If you want a preliminary idea of common sizes and how an opening is measured, first read the guide to standard window dimensions.

At this stage it’s normal to receive an indicative price bracket, not a quote. Be wary of anyone who gives you a precise figure over the phone without having seen anything: without a survey, any number is a guess.

Stage 2 — Site visit and survey: why it’s the most important stage

This is the heart of “custom-made”. The survey is the precise on-site measurement of the openings carried out by a technician, and it’s the stage on which the success of the whole order hinges.

Why does it matter so much? Because a custom-made window is built to the actual measurements of your opening, and that opening is almost never perfectly square. An experienced technician doesn’t just measure width and height: they check the diagonals, the plumb, the presence of sub-frames, the wall thickness, the sill, and where shutters or roller blind boxes run.

Who should carry out the survey? Ideally whoever will then be responsible for installation, so that the measurement and the responsibility for it stay in the same hands. If you have the windows built to a measurement you’ve taken yourself, the risk in the event of an error is entirely yours; when whoever installs carries out the survey, a measurement error becomes their problem. With LMT’s supply-only model in Italy, the survey is handled by your fitter, not by whoever produces the windows: that’s why it should be measured by whoever will then fit them.

It’s also worth clarifying the difference between the opening measurement and the window measurement: there is always a perimeter clearance between the two (indicatively a few millimetres per side, as an example) needed for installation and sealing. This is normal, and part of a job done properly.

What you can do to make the survey easier:

• Clear the openings as far as possible, so the technician can measure and inspect comfortably.
• Point out known issues: a window that doesn’t close properly, an area with mould, a damaged sill.
• Ask whether the survey is free of charge and without obligation (it usually is).

Stage 3 — The choices: profile, glass, hardware, finishes

With the openings surveyed, you decide what you’re actually buying. This is the stage where a good supplier guides you without pushing you, explaining the reasoning behind each option. There are four main decisions.

1. The material and the profile. PVC, aluminium, timber or timber-aluminium. For most homes in Italy, PVC is the most balanced choice between insulation, maintenance and price: if that’s the direction you’re heading, start with the complete guide to PVC windows. Within the material, you then choose the profile system (for example, a specific Salamander system, manufactured in Germany), which determines thickness, number of chambers and performance.

2. The glass. Double or triple glazing, low-emissivity glass, and any acoustic or safety panes. This is the choice that has the biggest impact on thermal and acoustic insulation: it always starts from the problem you’re trying to solve.

3. The hardware. The opening and closing mechanism: it determines how the sash moves (casement, top-hung, tilt-and-turn) and the level of anti-break-in security.

4. Finishes and opening types. Interior and exterior colour (including wood-effect finishes), handle, and above all how the windows open in each room. Choosing the wrong opening type is something you only “discover” once you’re living in the house.

Choice	What you decide	What should guide you
Material and profile	Thickness, chambers, base performance	Desired insulation, budget, appearance
Glass	Thermal, acoustic, safety	The problem to solve (cold? noise?)
Hardware	Opening method, security	Ease of use, exposure, security
Finishes and opening types	Colours, handles, opening type	Appearance, how the rooms are used

Practical tip: decide one room at a time, imagining how you live in it. A window above a kitchen sink has different requirements from one in a bedroom. This isn’t a decision to make hastily at the bottom of a quote.

Stage 4 — Quote and specification: read before signing

Once the choices are made, the quote arrives, accompanied (with a well-organised supplier) by a specification describing in detail what is included. This is the moment to slow down and read.

How to assess an offer item by item is a topic in its own right: you’ll find it in the dedicated guide on what to check in a window quote. In summary, a good quote should state at least: the profile system and thickness, the window’s Uw value, glass type, hardware and brand, installation type, reference to CE marking under EN 14351-1, quantities and measurements, timeframes, warranties and payment terms.

One thing worth understanding here: installation is a separate line item, not something automatically included “by default”. An excellent window installed poorly loses most of its value. It’s best for the quote to specify that installation follows a recognised standard: in Italy the reference is UNI 11673, and we explain what that means in the guide on UNI 11673 installation, what it means.

What to ask before signing:

• Is the quote binding on price, and for how long is it valid?
• Is installation included, and following which standard?
• What is NOT included (disposal of old windows, building works, flashing, roller shutters)?
• What are the deposit and balance, and which stages are they tied to?

Stage 5 — Order confirmation: what changes

When you sign and pay the deposit, the order becomes binding: the manufacturer sends your windows into production, built to your measurements. From this point, changes become difficult or costly, because every piece is cut and assembled specifically for you: it isn’t a stock product that can simply be swapped.

For this reason, you should only sign once you’ve cleared up every doubt about stages 3 and 4. It’s perfectly legitimate to take a few extra days to decide on colours and opening types: better an extra week before ordering than second thoughts afterwards, once the profiles have already been cut.

At confirmation, make sure you have in writing the signed specification detailing exactly what you’ve ordered, the indicative delivery timeframes, and the payment terms: these are your reference point at delivery.

Stage 6 — Production lead times (indicative)

This is by far the most common question: “When will they arrive?”. The honest answer is that it depends, and anyone who gives you an exact date before order confirmation is guessing.

The production lead times for a custom-made window, as an example and as an order of magnitude, are generally measured in a few weeks from order confirmation, not days. The actual range depends on several factors:

Factor	Indicative effect on lead times
Product type	Special solutions or triple glazing tend to extend it
Colours and finishes	Unusual colours can take longer
Time of year	Lead times stretch out during peak periods
Quantity	A whole house takes longer than a single window
Material availability	Specific glass or hardware has an impact

The practical value of this stage is a single one: get the timeframes in writing at order confirmation, knowing they’re indicative and not a promise to the day. A reputable supplier gives you an honest estimate, not a sales slogan, and updates you if anything changes.

Stage 7 — Delivery

As the date approaches, the supplier arranges delivery to site; installation, when included, is handled by the fitter. On delivery, it’s good practice to check that what arrives matches the order: number of pieces, colours, opening type, accessories. The signed specification (stage 5) makes this check straightforward.

From here begins another chapter, installation, a trade in its own right which we don’t cover here as a step-by-step guide. As far as ordering is concerned, it’s enough to know that installation is part of the supply only when you’ve agreed it as such, and that installation done properly is what turns a good window into a good result.

When it’s NOT worth (or necessary) following the whole process

The process described is the “full” one, designed for a significant purchase. There are, however, situations where it should be calibrated with common sense.

• When you’re in a hurry and willing to compromise. If you need to replace a broken window quickly, a fully optimised custom-made solution with every choice weighed up may not be the way to go: sometimes a faster solution makes sense, as long as you’re aware of the trade-off.
• When the project is a single standard window. For a single opening of a common size, demanding the same level of documentation as a full renovation can be disproportionate. The essential items (product, Uw, glass, installation, CE marking) remain non-negotiable regardless.
• When you skip the survey to save time. Ordering to measurements you’ve taken yourself to “save time” is the most common false economy: if the measurement is wrong, the piece has to be remade and any time saved is lost entirely.
• When you confuse custom-made with extreme customisation. “Custom-made” means built to the measurements of your opening, not loaded with a thousand exotic options. Often the most balanced solution is also the most understated.

FAQ

How much time passes, on average, from first contact to delivery? As an indicative order of magnitude, it’s a matter of a few weeks from order confirmation to delivery, plus the days needed for the survey, the quote and your own decisions. The real figures vary by product, colours and time of year, and your supplier will confirm them to you in writing.

Should I take the measurements myself, or should whoever installs? It’s strongly advisable for whoever then fits the windows — your installer, with a technician, on site — to do it: that way the measurement and the responsibility in the event of an error stay in the same hands. With supply-only, as LMT works in Italy, the survey isn’t done by whoever produces the windows: it’s handled by the fitter you choose. If you take the measurements yourself to “save time”, the risk of an incorrectly sized piece falls on you.

Can I change the order after signing? It becomes difficult and often costly, because custom-made windows go into production cut to your measurements: they aren’t stock items. This is why choices about colour, glass and opening type need to be finalised before confirming the order. Taking a few extra days before signing is entirely normal.

What do I decide, and what does the window supplier decide? You decide the objectives and preferences: the problem to solve, the appearance, how you want the windows to open, the budget. The window supplier guides you on the technical choices (profile, glass, hardware) consistent with those objectives and carries out the survey.

Is installation included in the order? Only if you’ve agreed it, and it should be stated explicitly in the quote. Check that it’s included and that it follows a recognised standard such as UNI 11673. Details in the guide on what UNI 11673 installation means.

Do I need to pay a deposit? When? Generally yes: the deposit paid at order confirmation is what triggers production. The amount and the split between deposit and balance should be specified in the quote. For contractual matters, always have the document checked by a professional you trust: this article is a technical guide, not legal advice.

In summary

Ordering custom-made windows isn’t a leap in the dark: it’s a process with clear stages. First contact to frame the need, an on-site survey (the most important stage, ideally carried out by whoever then installs), room-by-room choices about the product, a careful read of the quote and specification, order confirmation once every doubt is cleared up, indicative production lead times, and finally delivery to be checked. There’s one common thread: decide calmly before signing, because afterwards the pieces are already made to measure.

If you’d like to explore the products before getting started, take a look at the pages on windows and doors and, in particular, on PVC windows.

Want to get off to the right start, with a quote that explains every choice item by item? Request a tailored quote: we guide you through the decisions and put everything that matters in writing, from the profile to the certifications. In Italy LMT produces and supplies the made-to-measure windows; the precise survey and installation are handled by your trusted fitter.