240v mats are recommended for large spaces. One thermostat can handle the amp load of up to 300 sq ft of heated area. Nuheat mats come in a variety of sizes, and multiple 240v mats can be controlled with one thermostat so long as the maximum area is not greater than 300 sq ft. These mats are suitable for use under tile, engineered hardwood and laminate flooring. All Nuheat mats are also UL listed for use in showers and other wet areas.