Insulate windows

Hi,

I use Insulbright installed over the frame and held in place with industrial velcro.

We've cut-fit Styrofoam insulation to fit windows frames when RVing at -40.

At Lowes you can buy the silver quilted insulation in rolls. We attached with velcro.

When I made the new curtains in our camper I used reclaimed upholstery fabric, made a double sided curtain and placed the silver covered bubble insulation inside. Attached to windows with velcro. I made the curtains large enough to fit the metal frames of the windows.

Two pieces of identical solid foam insulation with a cut-out in the center to be able to see outside.
In between the two pieces of board, I used heat shrink self stick storm window wrap and sandwiched it in between the two pieces of board. I used some glue to hold the two pieces together.
After seeing that everything fit nice, I painted it .
This particular piece stays in place by cutting it snug to allow the emergency handles and top of the valance to hold it in place.
On the other cab-over windows, double sides tape could be used .

It seems to work very well with no condensation in nigh time temps down to -30F. My non slide TC warms up to 70-75F using the furnace . An electric heater keeps it warm enough (60F) for daytime use.
I cover the door using an insulated drape . That helps a lot being those doors leak a good amount of air.