Ecoo thermo reflective has been designed and made for the DIY market , if you currently have glass wool in your loft and want to increase your insulation values witout breaking the bank!,  this product is the one to go for, you would fix this to the underside of the rafters with staples and tape up all joints, Eco Thermo reflective will reflect heat out the house in summer keeping the house cool and in winter months reflect heat normaly lost back int the house.