I had this company put cavity insulation in in 2005 they have been back twice since but it is still not fixed 6 years later I still have a problem They used Rockwool I had the Rockwool guy out today he says they did not use the correct drill pattern or "blow" it in correctly so creating empty spaces resulting in cold damp areas they havent done the paperwork correctly so I have an unauthorised installation and no Building Regulation certificate Registered letters are ignored by the head office DONT TOUCH THEM