Wave curtains: the contemporary S-fold

A wave curtain has a flat heading that attaches at intervals to carriers, the small runners that slide along the track. The carriers are linked to each other at a fixed spacing. Where one carrier holds the fabric forward and the next lets it fall back, the curtain forms a smooth, alternating fold, in front of the track and then behind it, all the way along.

Because the spacing between carriers is set, the folds are set too. Draw the curtains across the window and the S-curve keeps the same depth; pull them back and they close up evenly into a neat bundle, each fold lying against the next. There is none of the bunching at one end and stretching at the other that a gathered heading can suffer.

That regularity is the whole point of wave. It gives a curtain the calm, repeating rhythm that suits a modern interior, and it looks as deliberate half drawn as it does fully open or closed. The heading itself is plain, with no gathers or pleats at the top, so the eye reads the folds rather than the fixing.

A wave curtain cannot hang from a pole. It needs a track with carriers made to hold it, and the track is chosen with the curtain rather than afterwards. The spacing of the carriers sets the depth of the folds, and the length of the track sets where the curtains stack when they are open.

The track is also the part you see least. With the fabric folding in front of it, a wave track mostly disappears behind the curtain, leaving an unbroken line of folds across the top of the window. That is a large part of the clean look, and one reason wave is often chosen for rooms where a pole with finials would feel fussy.

Our fitters supply and fit the track as part of the job, set it level, attach the curtains to the carriers and check with you that the pair draws smoothly before they leave. On a wide window or a run of doors, the track can carry a single curtain drawing to one side or a pair meeting in the middle, and your advisor will talk through which suits the way you use the room.

Most curtains look their best either fully open or fully closed. Half drawn, a gathered heading bunches at one point and stretches at another, and a pleated heading loses its rhythm. Wave does not, because every fold is held at the same spacing by the carriers.

That makes a real difference on windows that spend much of the day partly covered. A south-facing room where the curtains are drawn part way to keep the sun off the sofa. A bedroom where one curtain stays across a window overlooked by the house next door. A kitchen-diner where a long run of glass is half closed in the evening. In each case, the curtain still looks finished.

The even folds also suit fabrics that benefit from a steady rhythm, such as stripes, or a plain fabric with a heavy texture, where the regular curve shows the fabric off rather than crumpling it. Very stiff fabrics can resist the curve, and very soft ones need the right lining to hold it; your advisor will point you towards fabrics that fold well.

Wave curtains fold neatly when open, but they still need somewhere to go. On a wide window or a run of glazed doors, the stack is a real width of fabric, and the track has to carry on past the glass for the curtains to clear it completely.

On most wide windows that means a run of wall at one or both sides. Bi-fold and sliding doors often have it; a window set close to a corner, a kitchen unit or a chimney breast may not. Where the wall is only on one side, a single wave curtain drawing to that side can work well, and a wide expanse of glass often looks calmer with one long curtain than with a pair.

Working out the stack is part of measuring the window. Your advisor measures the wall either side as well as the opening, and tells you on the day how far the track needs to run and whether the glass will be clear when the curtains are open. For wide glazed doors in particular, our patio and bi-fold door blinds guide compares curtains with the blind options.

A curtain track can be fixed to the wall above the window or, where the ceiling is suitable, to the ceiling itself. Ceiling fixing is one of the things wave does best. The curtain falls from ceiling to floor in one continuous run of folds, which makes a room look taller and turns a wall of glass into a single soft surface when the curtains are drawn.

It suits modern extensions, new builds with windows that run almost to the ceiling, and any room where there is simply no wall above the window for a bracket. It also avoids the band of bare wall above a pole that can make a tall window look shorter than it is.

Whether a ceiling fixing works depends on what the ceiling is made of and what is in it or above it: joists, plasterboard, recessed lights and so on. Your advisor looks at the ceiling as well as the window and will tell you on the day what our fitters can fix to. If the track has to go on the wall, a wave curtain still looks clean; it simply starts a little lower.

Some wave tracks are drawn by a cord rather than by hand, which keeps hands off the fabric and the folds even. If there are young children in the house, that cord deserves the same thought as a blind cord.

The safety standard for internal blinds, BS EN 13120, does not apply to curtains. That does not make a corded track safe: RoSPA points out that corded curtain tracks can pose the same risks as blinds, and should be part of any check on cord and chain safety. In practice that means keeping the cord out of a child's reach, keeping cots, beds and anything a child could climb away from it, or choosing curtains that are simply drawn by hand.

If young children will be in the room, tell your advisor at the appointment, so the way the curtains are drawn is part of the conversation from the start rather than an afterthought. Our guide to blind cord child safety covers cords, chains and safety devices in more detail.

Wave belongs in modern and open-plan rooms: kitchen-diners with a wall of glass onto the garden, living rooms with bi-fold doors, new builds and extensions with wide windows and plain walls. The regular folds sit comfortably with clean lines, flat ceilings and simple furniture, and the hidden track keeps the top of the window uncluttered.

It also works well in a bedroom, particularly with a blackout lining and a track fixed close under the ceiling, which leaves less of a gap for light to escape over the top than a pole standing off the wall.

Wave is harder to love in a small, traditional room. On a narrow cottage window, with no wall to stack onto, it can look like a curtain that has wandered in from somewhere else, and in a formal period room, pinch pleat usually carries the character better. A bay is possible only where the track can follow the shape of the bay, which your advisor will confirm when they measure.