I need help figuring this out

Sapphyr

At our house we have this reflective stuff covering all but two of the windows. Well it's 62 degrees in the house right now because it was cold last night. And I don't know that we'll have anymore 90+ degree days until March/April. I'd like to try to keep the house warm/comfortable during the day at least since we don't have any heat here. If I take those foil things off the windows it should theoretically let the house warm up during the day but then the house would be colder at night? I've never dealt with these before living out in this region. I am going to put the weather plastic up though for the winter to help with drafts and redo the stripping on the doors.

crackerjackprinter

Is it foil or something else? I know a lot of people use foil around here.

Sapphyr

It's not tin foil.  It looks like bubble wrap covered in tin foil though.  I've seen this stuff at Lowe's recently when I was looking for a different alternative for the windows.  But, it's shiny on both sides.  I'd like to put something else up on the windows like the UV blocking car window tint.  I don't know.  I'm trying to keep the warmth in for the winter but also wonder if by taking them down that they'll make it