Pioneering Eco-Friendly Hot Tub Solutions in the UK. As a leading manufacturer, RotoSpa is celebrated for its innovative designs that blend sustainability with cutting-edge technology. Our hot tubs, renowned for their durability and energy efficiency, are crafted using a unique dual shot-moulding process and Ultra-High Blow Polyethylene Foam Insulation. This state-of-the-art insulation system enables our hot tubs to achieve up to a 35% reduction in energy consumption.