found this interesting cork product.

Cork Floating Flooring This looks interesting for those trying to soundproof the upstairs bedroom. If you click the specs page it gives all the detail. I also wonder what the absorption coefficient would be as it's 1/2" thick so it must absorb some of the high-mids (the surface finish would reflect highs I presume.) anyone ever used this ?? It's expensive - $6.50 - $8.00/sqft. cheers john

Lumber Liquidators in the US has something very similar for right under $4 a square foot. I am interested in using cork on the ceiling (unfinished) first because of it's acoustic properties, but also because it's visually attractive. I found raw cork in 1/4 inch thick rolls for $120 for 200 square feet.