Installing Dacron covering at high room temperatures

[tigger_na]

Dear Forumites
Dacron contracts with higher temperatures and expands in lower temperatures, right? If I now mount my covering with 38°C room temperature, won't it be loose and sloppy when I fly at 5°C or lower in winter? If yes, what do I do?
Blue skies
Arthur

[German]

Cool the room down before covering

[tigger_na]

The "room" is rather big. In the States I hear that they sometimes pack the wings with snow before tying things up.