Hannah asked in the Ask me Anything:
The answer to this is... it's complicated. Which, by the way, is the answer to a lot of general questions regarding things in the Middle Ages. The reason for this is a) our source material, which often does not cover things in detail; b) the fact that many things were probably just as varied and different from household to household and region to region as cooking recipes are; c) the Middle Ages are a long time, and things also changed over that time.
The sources we have for use of fabric (types) in garments are mostly the garments themselves and in second rank descriptions of clothing, both in form of literature and of lists or inventories. Both of them have their pitfalls. Extant garments are few and far in between, and if they are archaeological textile finds, there's almost no chance for linen or other plant fibres to survive. From extant clothing, we do have evidence for wool and silk upper garments, plant fibre fabric linings for these upper garments, and plant fibre fabric used for undergarments. As far as I know, there's no evidence for plant fibre fabrics as upper garments.
The High Medieval German texts mention plant fibre fabrics for undergarments and silk or wool for upper garments. Silk can also be used for undergarments, in some cases, according to these texts.
So - we have good evidence for the use of silk and wool for upper garments, and for the use of plant fibre fabrics (which could be linen, nettle, hemp, or cotton) for linings and undergarments. This, by the way, includes padded and quilted undergarments. There's no good evidence for the widespread use of wool as undergarment fabric to my knowledge, and there's no good evidence for the use of plant fibre fabrics as upper garments. Both cannot be excluded completely, of course.
When you go into detail more, it gets even more complicated, as the preferred weave types for wool and silk fabrics also change over time, according to the amounts of (mostly wool) fabric scraps found in archaeological context. Plainweave, though, can be found through all ages in quite large quantities - so if in doubt when looking for fabrics, this is your friend. For the decision on which fabric to use for clothing regarding a specific time and area, I'd recommend to try and find out about textile finds from there, and then try and find a fabric that is approximating the finds - which can, unfortunately, be quite a challenge, as many of the "typical" medieval fabrics are not available today anymore.
I have this question which kind of follows me around since I got involved in all this medieval stuff. It is a quite common topic and I have of course discussed it with fellow fans of the Middle Ages but still I am very unsatisfied with the answers. So, here it comes: which fabrics were used for which type of garments (e.g. is it true that linen was only used for undergarments?). Or do we just not know enough about this yet?
The answer to this is... it's complicated. Which, by the way, is the answer to a lot of general questions regarding things in the Middle Ages. The reason for this is a) our source material, which often does not cover things in detail; b) the fact that many things were probably just as varied and different from household to household and region to region as cooking recipes are; c) the Middle Ages are a long time, and things also changed over that time.
The sources we have for use of fabric (types) in garments are mostly the garments themselves and in second rank descriptions of clothing, both in form of literature and of lists or inventories. Both of them have their pitfalls. Extant garments are few and far in between, and if they are archaeological textile finds, there's almost no chance for linen or other plant fibres to survive. From extant clothing, we do have evidence for wool and silk upper garments, plant fibre fabric linings for these upper garments, and plant fibre fabric used for undergarments. As far as I know, there's no evidence for plant fibre fabrics as upper garments.
The High Medieval German texts mention plant fibre fabrics for undergarments and silk or wool for upper garments. Silk can also be used for undergarments, in some cases, according to these texts.
So - we have good evidence for the use of silk and wool for upper garments, and for the use of plant fibre fabrics (which could be linen, nettle, hemp, or cotton) for linings and undergarments. This, by the way, includes padded and quilted undergarments. There's no good evidence for the widespread use of wool as undergarment fabric to my knowledge, and there's no good evidence for the use of plant fibre fabrics as upper garments. Both cannot be excluded completely, of course.
When you go into detail more, it gets even more complicated, as the preferred weave types for wool and silk fabrics also change over time, according to the amounts of (mostly wool) fabric scraps found in archaeological context. Plainweave, though, can be found through all ages in quite large quantities - so if in doubt when looking for fabrics, this is your friend. For the decision on which fabric to use for clothing regarding a specific time and area, I'd recommend to try and find out about textile finds from there, and then try and find a fabric that is approximating the finds - which can, unfortunately, be quite a challenge, as many of the "typical" medieval fabrics are not available today anymore.