Had Mark Insulation round yesterday to top up my loft insulation. Used nine rolls (64sq m) of 200mm blanket, re-jacketed the coldwater tank, left the tops of two downlighters exposed, draughtproofed the access hatch, would have lagged the water pipes had they needed it, about three hours, four bedroom house, , left a roll of duct tape behind, by accident, cost £195. Very satisfied.