Have a piece of thick MDF cut to fit it like a child’s wooden jigsaw - insert it at night - if it’s covered with wadding and fabric it will squeeze in and stop the light. In the daytime just sit it on the floor or keep it under the bed.

As a professional in the industry and also have a 360cm bifold door at home i know the issue all too well. It all comes down to the budget you want to spend. I would have to recommend use a curtain track so you can get good support all the way across the track and know that it is sturdy to hold a heavyish pair of curtains. You will have to go with a metal curtain track of some description as the plastic ones are just not substantial enough and will not work as smoothly as the aluminium ones. You will certainly be able to have a single curtain pull to one side with a good quality track. Now the main element of this is the heading style for these curtains. The modern wave headings give you a beautiful pleat that will always look beautiful. Any of our metal tracks would be substantial enough and some of them can be upgraded to 60mm or 80mm wave heading. https://www.direct-fabrics.co.uk/curtain-tracks/metal Price for a 350cm would be around £40 upwards for medium domestic. going upto a heavy duty around £150 even more for silent gliss products. Fitting and installation with a qualified CSCS fitter would be around £120 maybe more depending on location. However to note you will have curtains right infront of a beautiful bifold door that will obstruct light coming in through the windows. I would suggest shaping the track outside the reveal but the book cases are in the way. Perfect Fit Blinds An alternative if you want the light to continue to come in is perfect fit blinds these work as frames that go out side the rubber seals of the window and allow a secondary frame to be mounted without any drilling into the window. This means you can fit them quickly and easily. A pleated blind would look incredible. A further option would be electric curtain tracks that fold to the left or right. These would be around £1000 Best option for cost Other options a light unlined hotel weight dimout pair of curtains these would be 95% blackout and you wouldnt see through them, with an eyelet heading top fixed inside the reveal with recess brackets. would work well. Really simple you would have 32 eyelets on a 4 width pair. not quite 100% fullness but would still look very clean. This would take up approx 16cm per side. But would be stacked back beautifully https://www.direct-fabrics.co.uk/recess-curtain-pole-kit.html Hope this gives you some ideas. If you would like some samples let the team know www.direct-fabrics.co.uk

Hi Lee- the window recess is actually a bonus in this case because it gives you sufficient depth for the 2 blind mechanisms. Plus the additional recess into the ceiling will help as well because it will disguise hanging the blinds at slightly different heights, eg one rod above the other, which you will likely want to do to get both blinds as close to the window as possible. The closer the blind the less light through the sides. I would recommend you get a standard roll roller blind, eg you want the fabric to go down the back of the roll. We’ve had really good luck ordering from Tuiss in the past for our roller blinds, and they do Romans’ as well. One thing you might also want to look at is cassette blinds, which have fixed side rails and thus offer better blackout and thermal coverage. We have a “Velux Duo” on a loft window and it’s terrific. It would give you a different option to combine a pull-up bottom mounted sheer blind to hide passerby (but keep the upper part of the window uncovered for better light) along with a traditional top mounted roman/roller blind for nighttime cover.

My daughter had shutters fitted at great expense and I found they made their room dark, I know people loke them, but I dont! If you want to buy curtains that will last when you change the colour of your walls, go for plain off white/ reamcream/linen, in a good quality material. Patterned curtains matching your present colour scheme can tie you to the same colour scheme if you fancy a change, unless you like getting new cheaper curtains regularly, I’d stick to plain, good quality off white, decent quality is worth paying for, it works out cheaper in the end!