Turning lined curtains so width becomes length; possible?

[ComtesseDeSpair]

We have two enormous windows in our living room which require very long curtains - 390cm. There's absolutely nowhere which does this sort of drop ready-made and even most made-to-measure services won't make up a drop of longer than 300cm; quotes from a couple that do were upwards of £2,000. Even buying fabric and making up my own runs to at least £500 per pair for good-quality heavy fabric and linings.

I've found some beautiful, heavy Laura Ashley curtains going cheap on eBay. Each curtain is 420cm wide with a 200cm drop. They are fully lined. Is it possible (and, I suppose, also fairly easy) to somehow 'turn' the curtains around so that the 420cm width becomes the drop? By removing the header tape currently at the top and restitching a new piece along one side of the current width? They are ungathered, so no gathering to contend with. Would the lining pose any problems doing this? I'm reasonably handy with a sewing machine for basic stitching so more than willing to give it a go if there's a good chance it'll work.

Thanks :)

Sounds like it would work to me. Once the header tape is off you might find you need a larger hem or to cut some material off of its not looking too neat. I just made some curtains myself and didn't bother with header tape, I just made a pocket at the top which has worked really well. they are also fairly giant drop wise, 300cm. They're so high that the way you hang them isnt so obvious.

I did this last year with velvet curtains in bedroom, including adding a strip across bottom edge to get exact size I wanted. They worked very well, (and have been admired) but with anything patterned you need to be sure they look good turned 90 degrees.

I had the same problem with our bay window.
In the end I bought the longest drop curtains I could fromb&q and an extra pair . I then stitched a border to the bottom of each curtain cut from the spare pair. Cost me about £120.

Cant see any problem if you are handy with a sewing machine.But do e careful about how these curtains are made up.Usually very wide curtains are actually 2 or even 3 lengths sewn together.This would not look good as widths instead unless they were very well made indeed.

Also check for weights. If they are weighted, you'll need to remove them and probably reset them at the new bottom for them to hang/sit well.