Happened to notice a new build going up and dump some goodies in a skip as they are just doing the snagging. Managed to get around 50 brand new, 7 newton blocks. Movin that lot certainly burnt a few calories! Theres still more in there, but imagine they'll be gone by the time I go back! A couple of years ago I managed to find a skip near a commercial build which had around 6 bales of shrink wrapped soundpoofing rockwool slabs.
Dave