External thermal blinds for caravans

As you will know, the insulated screens for MHs fix by being trapped in the cab doors and fitting around the mirrors. I’ve never heard of anything similar for caravans and don’t know how you would secure them if they exist. Also, it would be another bulky lump to carry with you for occasional use as you will not always be pitched with the front facing the sun.

For 40 years we pulled the blinds down to keep the sun out without a problem. If it concerns you, pull them part way to leave a gap for air flow.

You could invest in a caravan front  travel cover and put it on if required on sites

I was always wary of having them fully closed on our caravan for the reasons you quote. They do get incredibly hot. Similarly with the side windows on our MH. However, their design means you can have part solid, part fly blind, which means you can leave a narrow strip at the top to let the heat build up out.

You could of course close the curtains, leaving the blinds rolled up, and even pull down the fly screens too. They would not reflect the sunlight back into the windows, which would I hope he in the ventilation position in any case allowing some air flow through the van.

How about making fabric sleeves that slide over the individual windows?

I know in days of yore there was a track at the top of the windows. The French often had slide in blinds for the outside of the windows.

 If it becomes too hot, what we do is open the windows, pull the fly-screens down and the silvered blinds partially down. It makes the place noticeably cooler and doesn't damage either windows or blinds.