I.K.O. manufactures a layered fibreglass shingle in the Cambridge line that carries a Lifetime manufaturers warranty. Our Cambridge premium architectural shingle provides durability, low maintenance and the great looks of a shake-like appearance at a very attractive price. They’re built to last with double-layer construction and a tough, modified sealant for superior tear strength values and greater resistance to high winds.They come in 12 colours and cover 33.3 sq. ft. per bundle. It is recommended that an underlayment is used below a 6/12 pitch.