ROCKWOOL FLEXI® has been designed as a multi-use, dual purpose acoustic and thermal mineral wool insulation with a unique flexible edge along one side. The ROCKWOOL FLEXI® slab is manufactured with the patented flexible edge which ensures a perfect fit is maintained between the insulation and the supporting framework. The insulation can be fitted between fresh timber and will expand into the wider space as the timber dries out and shrinks back. Other types of insulation can often become displaced resulting in cold spots or poor acoustics. ROCKWOOL FLEXI® provides excellent thermal and acoustic performance as well as being A1 classified non-combustible for fire resistance.