A made-to-measure door should fit the way you live, not force your project around a standard size. Whether you are opening a kitchen extension to the garden, replacing dated patio doors or specifying a larger scheme for a client, knowing how to order bespoke doors helps you make the key decisions in the right order. It also reduces the risk of costly delays, incorrect measurements and compromises on performance.
Bespoke does not need to mean complicated. The strongest results come from starting with the opening and the purpose of the space, then working through configuration, material, glass and finishing details before placing the order.
Start with what the door needs to do
Before comparing frame colours or sightlines, decide what you need the door to achieve. A set of doors between a kitchen and patio may need to maximise light, improve the connection to the garden and provide a wide clear opening in summer. Doors for a side return, balcony or exposed elevation may put weather resistance, security and thermal performance first.
This early brief shapes every later choice. For example, bifold doors are a natural choice where a wide opening is the priority, as the panels stack neatly to one or both sides. Sliding doors retain large areas of glass and slim visual interruptions, making them particularly effective when you want uninterrupted garden views. French doors may suit a smaller opening, a period-style property or a room where only occasional access is required.
Think about daily use as well as the finished look. Ask who will use the doors, where furniture will sit, how often you want to open them fully and whether the threshold needs to be as level as possible. For trade buyers, this is also the point to confirm the architect’s drawings, planning requirements and the overall build-up of the wall, floor and roof.
How to order bespoke doors: measure the opening correctly
Accurate measurements are the foundation of a successful bespoke order. Measure the structural opening, sometimes called the brickwork opening, rather than the old frame or the visible glass area. Take the width at the top, middle and bottom, and the height at the left, centre and right. Use the smallest measurement in each direction as your working figure.
Do not assume an opening is square. Even newer extensions can have small variations that affect fitting. Note the diagonal measurements too, as these help identify whether the aperture is out of square. A qualified installer can assess this on site, but providing clear initial dimensions makes product selection and quotation far more straightforward.
You also need to allow for installation tolerances. The finished frame must not be manufactured to exactly the same size as the structural opening, because fitters need appropriate space to position, pack and seal it correctly. The exact deduction depends on the system, installation method and site conditions. It is better to confirm this with the supplier before finalising dimensions than make assumptions based on a previous project.
Record the following details alongside your measurements:
- Opening width, height and diagonals
- Internal and external floor levels, including any finished floor coverings
- Wall construction and available fixing points
- Existing obstructions, such as pipes, gutters, radiators or roof overhangs
- Access for installation, including narrow side passages and upper-floor locations
A photograph of the opening from inside and outside is often just as useful as a list of figures. It gives the technical team context around reveals, drainage, threshold levels and access.
Check finished floor levels early
Threshold decisions can affect both the appearance and practicality of the installation. A low threshold gives a cleaner transition from inside to out and can be useful for accessibility, but it needs careful detailing so water drains away from the property. The external patio or decking level must be planned around the system’s drainage requirements.
This is particularly important on extensions where flooring, screed and external landscaping are still being designed. Resolve the door threshold before the builders complete these elements. Retrofitting a solution after the patio has been laid can be difficult and expensive.
Choose the right configuration for the opening
Once you know the available size, choose a door arrangement that works in real life. With bifolds, consider the number of panels, panel widths, whether they fold left, right or split from the centre, and whether a traffic door is needed for quick everyday access. A traffic door allows you to step outside without folding back the full set, which many households find useful.
With sliding doors, consider the number of tracks and panels. A two-panel slider can offer a simple, balanced arrangement, while three or four panels may suit wider openings. More tracks can create a larger opening, although they also introduce more frame lines and affect the depth of the system. There is no single best arrangement – it depends on how much open space you want versus how much uninterrupted glazing you prefer.
Opening direction matters too. Think about pathways, dining areas, kitchen islands and external seating. A door that looks right on a plan can become awkward if an open panel blocks a route through the room or out onto the terrace.
Specify material, colour and sightlines
Aluminium is a popular choice for larger glazed doors because it is strong, low-maintenance and available in a broad choice of finishes. Its strength supports slim frames and generous glass panels, helping to brighten your home without making the structure feel heavy. It is often well suited to contemporary extensions, garden rooms and design-led renovation projects.
uPVC can be a practical, value-focused option for certain door styles and sizes. It offers good thermal performance and straightforward maintenance, although frame profiles are generally wider than aluminium. Heritage-style aluminium systems can provide the slim, steel-look appearance that works especially well in period properties and industrial-inspired interiors.
Colour should be considered in relation to both the property and the room. Anthracite grey remains a versatile option, while black creates stronger contrast and lighter tones can soften a traditional elevation. A different colour inside and out may be available on some systems, allowing you to coordinate the external façade with the interior scheme. Check the finish specification carefully, particularly where the doors will be exposed to strong sun, coastal conditions or frequent use.
Select glass for comfort as well as appearance
The glass makes up most of a glazed door, so it has a major effect on warmth, solar gain, privacy and sound. Modern double glazing is suitable for many projects, while triple glazing can improve thermal performance in the right system and location. However, triple glazing is heavier and may not always be the best value or practical choice for every configuration. A well-specified double-glazed unit can be an excellent solution.
For south- or west-facing rooms with extensive glazing, solar-control glass can help manage overheating and glare. It is worth considering alongside shading, ventilation and the overall design of the extension. Privacy glass may suit overlooked boundaries, bathrooms or side elevations, while acoustic glass can be valuable near busy roads or rail routes.
Ask for the relevant performance figures rather than choosing glass on a description alone. U-values indicate thermal performance, while security glass specifications and safety-glass requirements should be confirmed for doors, low-level glazing and critical locations. For new-build and extension work, the final specification should support the project’s Building Regulations requirements.
Confirm hardware, security and practical details
Handles, hinges, locking systems and thresholds are not minor finishing touches. They determine how the doors feel every day. Choose a handle finish that works with the wider scheme, but prioritise a system that is comfortable to operate and suited to the door’s weight and configuration.
Security should be built into the specification from the start. Look for suitable multi-point locking, toughened or laminated safety glass where required, and products tested to relevant UK security standards. If your project needs a particular standard for building control, insurance or a development specification, raise it before ordering rather than after manufacture has begun.
Also confirm whether trickle vents are required. Ventilation rules and project circumstances vary, especially when replacing existing doors versus creating a new opening. Your installer or supplier can advise based on the property and scope of works.
Review drawings before production
A bespoke door order should be checked against a clear order drawing or confirmation document. This is the point to verify overall dimensions, frame colour, glass specification, opening direction, panel layout, handle position, threshold type and any accessories. Read it as if you were standing inside the room and looking out.
Do not approve the drawing until every point is right. Bespoke products are made to your agreed specification, so changes after production starts may not be possible or may involve additional cost. For a larger renovation, share the approved drawing with the builder, installer and kitchen or landscaping team so threshold levels and finishes stay coordinated.
Plan delivery and installation around the build
Made-to-measure doors need a dry, secure place to be stored before fitting. Confirm lead times at the quotation stage and avoid scheduling delivery before the opening is ready, unless secure storage is available. Large glazed units are heavy and need careful handling, so access should be assessed well in advance.
Check whether a lorry can reach the property, whether panels must travel through a house or side passage, and whether lifting equipment may be required. On tight urban sites, delivery and installation planning can be just as important as the product specification.
Horizon Windows and Doors can help customers work through configurations, technical details and product options before purchase, which is particularly useful where drawings are complex or measurements need a second check. It is a practical way to keep design ambition aligned with the realities of the opening and installation.
The best bespoke doors feel effortless once fitted: they open where you expect, frame the view you wanted and keep the room comfortable through every season. Take the time to specify them carefully, and your new opening can become one of the most rewarding parts of the project.
