Wool and Linen (Shatnez) in Separate Garments.
Are you allowed to wear two separate clothes, one wool and the other linen, such as a linen shirt with a woolen sweater or pants?
The Aish Rabbi Replies
The general rule is that if both of the garments can be removed without first removing the other one, they do not combine to be Shatnez. If however, for example, the shirt cannot possibly be removed without first removing the sweater, they do combine. Nevertheless, it is best to avoid such combinations, even if one can somehow remove the inner garment without the first removing the outer. (Sources: Shulchan Aruch Y.D. 300:4, Pitchei Teshuvah 6.)