Insulating windows with transparent film?

[HoppyFish]

Hi all. I live in a flat with a nice big double aspect lounge/dining room, with three large double glazed UPVC windows. The windows are bigger than normal, with a low cill, the windows measuring 1.68m high x 1.07m. It's lovely in summer but gets very cold in winter. The wall temperature isn't too cold and I'm fairly sure most heat is lost through the windows (or cold coming in?). I know lined curtains will help when I get them, but I wondered if anyone has experience of using transparent insulating film? For example:
https://www.amazon.co.uk/dp/B0B6V6MC76/ref=sspa_dk_detail_1?pd_rd_i=B0B6V6MC76&pd_rd_w=TUqcn&content-id=amzn1.sym.46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_p=46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_r=Z81D4P1T1SX8XMMEETWS&pd_rd_wg=BTdlO&pd_rd_r=d856ac1d-58a7-4e3d-b5a1-92c3675bafde&s=kitchen&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw&th=1
Many thanks!

I did this one year and I think it helped a little with heat loss, but when I removed it in the spring it pulled the paint from my window frames which was such a pain. Also, as it seals the whole window you can’t open any to freshen the house

so I’d say that if you have unpainted windows and extractor fans go for it, but otherwise be careful. Instead I put up insulated blinds behind the curtains and shut them as soon as the sun sets- then I got secondary glazing which is the best solution but obviously very expensive

I know you still want to be able to see out the window, but I've heard of people using bubble wrap to insulate windows. I don't know if you could make a blind from it and use blue tak to stick it to the window. If you want to open it up though, you could just roll the bubble wrap back up to the top.

If you own the flat, secondary double glazing would make the most sense as @Cactuscuddles says. You can unclip it after winter and store it until colder weather.

My neighbour has problems with drafty windows in the winter and she installed secondary glazing. It looks inoffensive and it really works to keep the drafts away. Once the Spring is here she simply takes it off and puts it all away until next Winter. Maybe this kind of thing would work better for you? A bigger initial outlay but something you can use time and time again.

I’ve just done this and it does make a difference. We’ve got draughty old sash windows though. We left one set de of the box bay window uncovered for ventilation.

I have used it before and it does make a difference. Like others have said, secondary magnetic glazing is probably a better bet you can order online and it is pretty easy to install.

I used to live in the coldest house in Christendom. Agree with everyone above: the film helps, bubble wrap's better if you don't mind the frosted bathroom window effect, and secondary window panels are better still.

If you're considering bubble wrap: spray the window with a bit of water to make it stick (flat side on the glass). Stays on all winter.

Thanks all! I will definitely look into secondary glazing. Seems like it might be a more sensible spend, even if the initial outlay is a bit more.

That film is really good, I used to do it in all my rented places back in the day, and it made a massive difference especially for the draughty sash windows that a lot of them had.
I also found you could often put one layer over the frames directly around the glass panes, and another over the main frames, making a kind of pauper's triple glazing.
It's definitely a bodge but for the money and ability to redo it every year in rented places it's perfect.