what I mean is I need something lightproof to cover 3'x5.5' - like on some of those grow tents you see advertised, where it's some kind of sheeting that gets rolled up to gain access.

I don't have enough space for a conventional hinged door - i've only got two foot in front of the cab, and my carpentry skills are not upto making two 1.5' doors.

I was thinking of using mylar but when I saw it in the growshop it was just too flimsy and creases up.

Thanks for the input though - appreciate any responses.