Wool fabrics have low thermal conductivity and, this means that they feel warm to the touch in cold weather and cool in warm weather. In humid conditions wool can remain comfortable and not clammy because it has the ability to absorb moisture vapour without feeling wet.
And if thats not enough, in these days of increasing allergies, wool even offers hypo-allergenic properties. It is naturally resistant to mould, mildew and dust mites, all of which can trigger allergic reactions. Not only is wool hypo allergenic, it also acts as an air purifier and reduces VOC's (volatile organic compounds) which are in the air all around us.