Since 1994, Knell Construction has installed millions of square feet of gypsum floor underlayments and sound control mat. Knell Construction has a proven track record of providing quality installations of gypcrete floor underlayments, sound mats, radiant heat flooring and hardrock concrete. Knell Construction serves both residential customers (radiant heat flooring, flooring level-ups, custom homes and remodels) and commercial customers (fire and sound rated systems for multi-family projects, hotels, senior living centers and commercial level-ups).