Sierra Premium Wood Fired 6 person Hot Tub | Hud-1 EZ Buildings The Sierra Premium Wood Fire Hot Tub comes ready to use no assembly required just connect the chimney spout. With the fiberglass liner which makes the hot tub extermly easy to clean and drain. The Sierra offers a rounded design, includes a Northern European slow growing Spruce which offers the highest quality and its' luxurious look. The Sierra Premium Wood burning fire place offers a much faster heating time heats within 1 1/2 - 2 hours. The Sierra Premium Wood burning hot tub comes ready to use no assembly required just connect the chimney spout and your ready to enjoy hours of relaxation.