Slimline doors and windows

Slimline doors and windows, also referred to as minimal, thin, and ultra-slim, are popular for their sleek, minimalist, modern design aluminium frames and large areas of glass, which allow more natural light into your home.

The various marketing terminology used to describe slim doors and slim windows vary across brands, making it difficult to differentiate and compare. The sightline width of frame depends on the frames construction and opening element configurations. High-end premium minimal framed ultra-slim windows are designed so the frame hides behind the structure, giving an all-glass look.

For your research, it is essential to understand the distinctions between slim, ultra-slim, minimal, and frameless doors and windows.

What are slimline doors and windows?

Are slimline doors and windows expensive?

It’s important to note that most slimline doors and windows are high-end premium products, which is reflected in their cost. However, this investment is justified by their engineering and design aesthetics, which are specifically intended for large sizes of contemporary architectural glazing. The slim and ultra-slim frames may appear thin face on, but they are deeper than regular windows and doors to retain the product’s performance, strength, and stability.

Virtually any type of door or window opening comes in a slim frame. Currently, no PVCu, timber, or hybrid systems, which are cheaper, offer dimensions even close to those of slim-frame aluminium products.

What is the difference between external and internal slimline doors and windows?

Exterior-quality slim doors and windows have insulated aluminium profiles and good glass specifications.

Interior doors and screens come in two versions: an exterior-grade door customised for interior use and a dedicated interior system that may be single-glazed and without profile insulation.

Sliding slim doors and ultra-slim

Slim sliding door sightlines start at around 16mm at the door mullions, which are part of a frame that divides or separates the frame into different sections. These doors are perfect for making an interior space look and feel bright and spacious.

Most sliding doors use a structurally bonded design, and all have a frame; hiding the frame and track gives the sliding door frame a slim appearance.

With slim and ultra-slim sliding doors, it’s crucial to understand that the frame proportions are not the same as the heavily marketed slim mullion . This is especially true when using the standard non-hidden installation method. By being aware of these differences, you can make a more informed choice.

Importantly, slimline sliding doors require several considerations when buying. To help you buy better, we have compiled the top 11 questions about slimline sliding doors and reviewed who makes the slimmest sliding door.

Bifolding slim doors

Bifold doors can’t achieve the large opening dimensions of sliding doors.

Slimline bifold doors typically have reduced dimensions at the door mullions, which are part of a frame that divides or separates the frame into different sections.

We’ve compiled a list of the slimmest bifolding door brands based on their door mullion sightlines. Other brands provide an even more minimal frame using the slide-and-turn opening design, and at the top end are the premium brands such as Sieger Lux.

Finally, more advanced bifold systems offer options for recessing the frame into the structure, creating even more minimalist sightlines. However, these also come at a very high price.

Thin profile floor-to-ceiling glazing and curtain walling

For modern homes, floor-to-ceiling glazing and curtain walling provide products spanning two or more floors. These products utilise designs found in commercial facades. The construction involves box mullions of various sizes, assembled on site and creating large screens.

In addition to providing large fixed glazing, these systems also integrate fully with sliding doors, bifolding doors, and opening windows. The slimness of these profiles depends especially on several factors: Location, wind loadings, supports and whether they are tied back to any floors are all essential requirements. Often, the larger the screen the thicker the mullions and frames. However, it’s common to find face widths of 50mm. Frame depths vary from 50mm to more than 200mm for the largest facades.

Interior slim windows, doors and screens

Products designed for internal use provide the best solution for slim interior doors, windows and screens. Near-frameless versions are also available. Steel-look glazing is one of the most sought-after among these thin-framed products.

Exterior-grade doors and windows can work inside the home in many situations. Still, the higher insulation and performance benefits of exterior windows and doors you pay extra for aren’t necessarily required internally. However, double glazing provides acoustic solutions when correctly chosen.

How to buy slim doors and windows

First, it’s important to decide how slim you want your doors and windows to be, what is structurally possible, and how much you are willing to pay.

It’s very important to engage with a professional supplier and installer who can demonstrate expertise and knowledge of slim doors and windows. These suppliers tend to go beyond regular window and door installations, providing a broader range of technical glass solutions such as glazed links, glass balustrades, fire-resistant glazing, glass floors, and other advanced glazing systems.

Slim doors and windows are usually best designed, made and fitted by the same business. We do not recommend buying these products directly online; high-end suppliers will have a showroom where you can see and touch the quality.

Please get in touch with us if you would like some advice on which brand and installer to contact.