Will cold or heat cause yarn and material to deteriate or get weaker in strength

Question:

Will cold or heat cause yarn and material to deteriate or get weaker in strength?

I have had to store some of my stuff like that in a shedd, because of lack of space. I appreciate any help that someone knows. Thanks in advance for your help.

Best Answer - Chosen by Asker:

This is going to depend on the material. Generally, if things didn't get wet or infested with bugs, they should be all right. The main danger isn't chemical decomposition or "deterioration," it's that your fabric gets damp and grows mildew or gets eaten by moth larvae etc.