Window treatments are a fundamental element of every home, and one of the primary aspects when designing any interior scheme. Equally important in terms of both functionality and style, they need to be very well considered (after all they’re quite an investment), however the world of window treatments can often be tough to navigate due to the sheer number of options and choices available.
We sat down with Kathryn McLeod, Founder of KLS Interiors – the go to window treatment manufacturer for London’s top interior designers – to give us the lowdown all things curtains, blinds and more. We have worked with Kathryn and her trusted team for ten years and as you’ll see when you read on, there is nothing Kathryn doesn’t know when it comes to this field, and no problem she can’t solve!
What are the starting points and main considerations when choosing window treatments?
I always try to consider the function of the space and how it might be used, as well as the shape and size of the window, and the aesthetics that the client is looking for. If the window is in a bedroom, is blackout required? If so, to what level? Curtain poles sit off the wall, so light will come up between the pole and the wall, therefore pelmets or a covered track (known as a lath and fascia) might be a better option. Alternatively, layered window treatments would work, such as a combination of a blind and a curtain as these block light in different places. Consider also where the window treatment will be fitted. Is there space for a pole above a window? Ideally you need around 10cm of wall space to fit a pole comfortably; a lath and fascia can be fitted into a much smaller gap.
You also need to consider what is going on in the area around the window, for example will joinery be fitted which may impact on the space available? If the client wants curtains, we need to ensure that wardrobe or cupboard doors can open without crashing into a curtain pole. If there is a sofa in front of the window, will this impact on the client’s ability to open and close curtains? If so, a corded track or curtain pole would make functionality much easier.
In terms of aesthetics, what style is the client drawn to? Some people prefer curtains, others blinds. Window treatments offer the opportunity to re-proportion a space. Fitting a blind outside a window reveal can make a window appear taller and more generous, for example, as well as maximising the light in a room. Similarly, making curtains wider than the window with a generous stack back will also allow as much light as possible to come into a room. Wall to wall curtains can add a sense of drama, as can a combination of blinds and curtains, which can pull in different colours and textures and soften a space.

When should you choose curtains, and when should you choose blinds?
Doors or tall, large windows lend themselves to curtains, whereas smaller windows may work better with blinds.
Is there space for the curtains to stack either side of the window? Or if a blind is preferred, would it look better inside the window frame or fitted above? If the property has small, low windows then blinds would work better, but preferably fitted outside the frame to give the impression that the window is taller, and so that the blind doesn’t block light or sit in the line of sight.
What is the client’s preference and how will they use the room? What are the proportions of the window? If there is a lot of wall space above the window then a blind might work better, or a combination of a blind and a curtain. In this scenario I would fit a curtain pole quite high up on the wall, with the blind fitted just below it to cover the wall space. This is a great way of re-proportioning a room and making the windows appear larger and more generous, and the combination of a curtain and blind can look luxurious.
Can you talk us through the main types of curtains and the practicalities of each?
Curtains generally fall into three categories: interlined (face fabric, lining and a middle layer called interlining which is available in a thinner and heavier weight), lined only, and sheer/unlined curtains. These look quite different to each other and fulfil a variety of functions.
We would usually create blackout curtains with blackout lining and interlining, making them thicker and warmer and more luxurious, but interlined curtains without blackout lining work well in most spaces.

Lined only curtains I find only work well with certain fabrics, and generally better when lined with a contrast fabric rather than a standard cotton lining. Standard cotton linings will protect the fabric from damage from moisture and the sun’s rays, but they are a close weave, flat fabric and usually feel very different to the face fabric so often don’t work well together and lined only curtains can also appear thin and quite limp. Furthermore, the stitching of the lining to the face fabric is visible without interlining, you will see small dots on the sides and bottom where the lining is attached no matter how small the stitching. This is more visible still if the lining and face fabric are quite different textures, and particularly on curtains made from a fabric which is closely woven and flat in texture. However a good weight linen, lined with a thinner linen can hang beautifully, and the lack of interlining allows the curtain fabrics to hang in their natural state which can be lovely.

Unlined curtains are generally machine made so stitching will be visible, but when done neatly it offers a flat, clean finish. Unlined curtains don’t have to be particularly sheer and can be made with heavy as well as very sheer fabrics. The choice of fabric is key here, as it will hang in its natural state. Texture and colour can be used to great effect on unlined curtains but beware that when closed the light travelling through the curtain will take on the colour of the fabric, therefore darker, muddier colours will dim the light in a space.

The choice of hardware (poles, tracks, pelmets, lath and fascias) has visual and practical implications. Tracks are best used where a corded system, as opposed to drawn by hand, is needed. If fitting into a ceiling pocket, or under a pelmet or lath and fascia then tracks are almost always used. These are generally corded but don’t have to be. Cords can be removed if the client prefers hand drawn. Tracks are not particularly good looking items, so work best when hidden, but they can be supplied motorised so are often used on electric installations, again, preferably best hidden from view. Alternatively, many suppliers offer tracks that can be recessed into a ceiling, so that the bottom of the track sits flush with the ceiling line. This is a contemporary option and looks very effective in certain spaces. The curtains go right up to the ceiling which is elegant and offers great proportions. These work well on wide expanses of floor to ceiling glass.
Pelmets and lath and fascias are made from timber and are great for blackout as they eliminate light bleed at the top. As timber-made items, they can also be cut around awkward window frames and can fit into small spaces where poles cannot be installed. Lath and fascias are slim items with a 40mm fascia strip, usually covered in the same fabric as the curtains, but they can also be painted, and as such can ‘disappear’ visually into a window frame. The curtains sit in front of the fascia so when closed the curtains are full height to the top of the board, which is completely obscured and can look very elegant. Pelmets are making something of a comeback and can be shaped / trimmed as required so offer the chance to get quite creative! Pelmets don’t have to look traditional, and often work well in contemporary spaces if the design is quite pared back.



Poles come in all sorts of styles, from traditional to contemporary, and are available in different finishes and diameters so are incredibly adaptable in terms of your scheme. Thicker diameter poles, in wooden and metal plated finishes with rings, are generally more traditional. Thinner metal poles are more popular at the moment, as are French poles which curve back to the wall, and allow the curtains to stack back further away from the window. French poles work particularly well on windows with box frame shutters which project quite far from the wall, as the poles wrap around the deep frame and cover it at the sides. Always consider the space that the pole is fitting into before purchasing. For example, wooden poles in a thicker diameter will have quite large chunky rings, so just check that there is plenty of space for the rings to sit above the window. I would stay away from thinner diameter wooden poles which can look quite cheap and may bend under the weight of a heavy curtain. Metal poles come in a wide range of diameters and finishes to suit different schemes, and usually offer an extensive choice of finials from highly decorative to very simple. Poles can sometimes be available as corded (or electric) as well. In this case they may not have rings, and the curtain heading will sit directly under the pole for a neat finish.



What choices are there for curtain headings?
There are many choices for curtain headings, from traditional to contemporary and everything in between. Traditional options would be a pinch pleat (double or triple, often called a French pleat) or a goblet pleat. More contemporary headings would include a wave heading, or an inverted pleat.
Curtains usually sit below a pole, so rings are visible, but certain headings can be raised up to cover the ring and some of all of the pole. A gathered heading with a standup is quite successful at covering a pole but any heading with a standup will occupy more space (stack back) when the curtains are open. Tape headings such as pencil pleats are still used and are more economical in terms of manufacturing cost, but tape headings are usually machined onto the curtain so these look best under pelmets where the heading is tucked away. Pencil pleats are making a bit of a comeback and can also be hand made which looks lovely. A hand made heading offers the chance to choose the height of the heading (as tape headings are only available in limited sizes). Some unstructured headings are also increasingly used and are more adaptable in terms of style. We often make curtains with sew in hooks, and hook two hooks into one ring on a pole which makes a very natural, softer heading style which appears more relaxed.



Can you talk us through the main types of blinds and the practicalities of each?
Roman blinds are the most commonly used style of blind and can be made blackout and interlined. These are flat and square in appearance and fold neatly up into place when made properly! They are installed either on a track with a beaded chain, or more traditionally on a wooden covered 1 inch square batten with strings and a metal plated or wooden acorn. A cleat is used to secure the string to the wall and to hold the blind in its up position. Because of their flatness, roman blinds offer the opportunity to showcase a lovely fabric and can also be trimmed and bordered with fabric or braids, or even a more decorative bead or pom pom trim. Roman blinds can be made with a ‘waterfall’ design. Waterfall blinds have the rods spaced differently, which creates a stepped effect where the folds fall below one another. These blinds take up more space when in their up position but show more of the fabric.



Recently there has been a move towards a more ‘relaxed’ shape of blind, and rodless romans fall into this category as do London blinds. They are made much the same way as a standard roman blind however they don’t have rods, which gives are more natural look. Depending on the stiffness of the fabric chosen and the spacing of the rings the blind may appear more or less ’scooped’. As the rings are stitched directly onto the fabric itself, it’s safer to opt for a fabric with some weight, as thin, open weave fabrics can be damaged where the rings are stitched on when the blind is raised and lowered.
London blinds are more traditional and depending on the ring spacing and the mechanism used to operate the blind, they can have raised or dropped down sides. London blinds can be made with inverted pleats, often in a contrast fabric and are fuller and make more of a statement. More traditional still are Austrian or festoon blinds which are very full and use a lot of fabric. They are usually gathered on both the width and the length, and work better when static and not operated due to the time and patience required to ‘dress’ them into place.



Roller blinds are mostly functional rather than aesthetic items, often used under pelmets or behind curtains for example to add blackout, or a privacy (sheer) layer. However, you can also laminate your own fabric to make them a bit more interesting, or have a sheer fabric processed, which stiffens it and makes it possible to cut without fraying. Roller blind brackets are generally not very pretty (hence the need to cover them) but some companies such as Tilly’s make lovely brackets in plated finishes which smarten them up. Roller blinds have the added advantage of rolling up into a relatively small space which is ideal where space is tight or to allow as much light as possible into a room. They can also be made motorised and recessed into a ceiling (ideally with a blindspace box to completely conceal the blind when rolled up), for a contemporary finish.
Skylight blinds and cassette blinds are the last but by no means least category! Skylight blinds are often (though not always) motorised and can be blackout or various grades of sheer. They usually function in a similar fashion to a roller blind, where the fabric rolls on and off a barrel, and can be applied to flat or sloping windows but must be square/rectangular applications. These are often fitted into a concealed box or on a ’shelf’ which looks a bit like a frame. Pleated blinds are another option for skylights, these aren’t particularly attractive items but fold up into a small space due to the thinness of the fabric and the efficient folds. These are often seen in conservatories and have the added benefit of being available shaped for awkward or apex windows. Pleated blinds can also be used in vertical applications such as triangle shaped windows, and can also be manual/motorised/blackout and non-blackout fabric. Cassette blinds are basically roller blinds which sit inside a frame. Again they are not particularly attractive items, these blinds nevertheless serve a purpose where total blackout is required such as a cinema room or child’s bedroom. We usually try to fit these underneath a roman blind which covers the headrail box and draws the eye away from the cassette blind itself.
How high should curtains/blinds be positioned?
I usually try to position blinds and curtains fairly high up on a wall as they can help stretch the height of a room visually and add a better sense of proportion. Points to consider however with curtains is the available wall space. If positioning a pole high on a wall, will it leave too much space between the bottom of the pole and the top of the window? If so, this can look a little disjointed, and a blind may additionally be required to fill the space. Also consider the width of the pole or track relative to the window, to allow enough space for the curtains to stack away from the glass. Bear in mind that interlined curtains will take more stack back space than sheer, and that wider windows will also need more stack back space than narrower ones. Roman blinds can also be fitted outside the frame to great effect but if fitted higher than around 20cm or so, the client will need to make sure they don’t raise the blind too much when opening it, as nothing looks worse than a blind with a section of wall space below it! They should ideally be dressed to just below the window reveal/architrave.
What combination and style of window treatments would give the best blackout solution in a bedroom?
The belt and braces answer to this is a cassette blind which has a box at the top which the blind rolls up into, as well as a frame at the sides and sometimes the bottom. This eliminates all or virtually all light however the big downside is that they are not particularly beautiful items. Alternatively, a combination of curtains and blinds will give good blackout, however a board based window treatment will be much more effective then a pole which leave a gap between the curtain and the wall. In nurseries for example we will often recommend a pelmet with curtains and a blackout roller blind as this combination covers light ingress on all sides providing the curtains touch the floor.

What is the best option if you need privacy but still want to let light through?
Privacy is almost always a talking point during a consultation, and is usually required on some level, especially in city properties which tend to be more overlooked. The most functional option is a roller blind which rolls up into a small space, so is fairly discreet, and also gives a smart ‘flat’ appearance from the front of a property. These almost always roll down from the top, so will obscure the top of the window when down or partially down, but they can be made as ‘bottom up’ roller blinds which are fitted to the window sill and roll up from the bottom. These are string operated and on a spring tension system, so they can be lowered to the desired level and tied off on a clear. These are often popular where privacy is needed on the lower part of the window only and the client wants to retain a clear window space above.
Roman blinds function the similarly to roller blinds in that they fold down from the top of the window, but are much more aesthetic and can be made with or without rods depending on the look required.
A rodless sheer roman will look much like a sheer panel when down and have the benefit of not having visible horizontal rods running through it. A sheer panel is budget friendly and can be used in places where it will not need to be raised or lowered. It can be made with a loose hem for a more relaxed look, or with a clear bottom bar for a more structured appearance. We often install half height panels with rods to the top (and sometime also the bottom) of a sash window, which remains static and also cannot be used, however the use of a rod top and bottom to stretch the fabric out can look smart and offers a good solution for covering the lower half of the window only, at a reasonable cost. Rods can come in different plated finishes to suit the scheme if budget permits.
Recently there is a trend towards cafe curtains which can be made slot headed or on rings if additional functionality is required. These can look very pretty and can be made half, three quarter or full height depending on the look and the privacy requirement. None of these treatments have to be made in particularly sheer fabric, and there is a massive selection of material available to suit different levels of privacy, and different schemes.
Finally, I usually suggest that the privacy layer (which is almost always the closest window treatment to the glass) is harmonised at the front of a property. It can look quite untidy from the road or driveway if the privacy layers vary from room to room.

What fabrics work best for window treatments? Are there any to be avoided?
I would always suggest natural fibre fabrics, as they tend to hang better and stand the test of time, however, be cautious with using raw silk on a window treatment. On windows which get a lot of sun raw silk can turn brittle and tear quickly, particularly on the leading edges. Thin fabrics will generally need an interlining to make them look and feel better if not being made up as an unlined item. We normally use the thicker weight interlining on very thin fabrics as it stabilises the different layers and makes them work and look better together.
If working to a tight budget, how do you elevate the look of window treatments without breaking the bank?
You can find a good range of fabrics for a reasonable price so I would try to get the best value for money here. Also, some curtain poles are relatively inexpensive but try to stay away from any that have flimsy brackets as they may bend under the weight of a curtain, especially if used continuously. Machined headings can also be more economical as they are less labour intensive. I wouldn’t compromise on interlining however, as this looks much better and will help the curtains to last longer. Also, it is a false economy to go for short curtains, which don’t look nearly as good. Most curtain companies charge per width so you may end up spending the same amount on short curtains than long ones, so you would probably only be saving a bit on fabric costs.
You work with many leading interior design studios – what trends are you seeing coming through for window treatments? Likewise, what types of window treatments are considered outdated?
We are seeing more of a demand for cafe curtains, under sink curtains, and curtains that are applied to joinery (under counter pantry curtains, dressing room curtains and so on). There is also a move towards more relaxed and organic shaped window treatments, such as rodless roman blinds. However I am a great believer that traditional styles such as pelmets and London/festoon blinds should not be written off, and with the right fabric, in the right setting they can look stunning and quite contemporary.

KLS Interiors is a London based manufacturer of bespoke top end soft furnishings for the trade. They work with many of London and the UK’s top interior designers, developers and architects on a range of residential and commercial projects. Established in 2006, their experienced in house team of 21 staff conduct site surveys and consultations, project manage, manufacture and expertly install a full range of hand made products including curtains, blinds, cushions and upholstery from their North West London premises. They work extensively across the South of England and overseas. As long standing members of the Guild of Master Craftsmen they are committed to quality, but also to reliability.