FloorMuffler UltraSeal Acoustic Underlayment the premium choice in flooring underlayment. It is ideal for use with laminate, engineered and solid hardwood flooring installations. FloorMuffler can be used and excels with floating and glue down applications. FloorMuffler boasts the most effective acoustic sound barrier on the market which deadens any hollow sounds and effectively creates a sound barrier between levels of your home. Along with its superior sound deadening, FloorMuffler acts as a remarkable moisture barrier exceeding industry standards by 700%.