Customer ServiceFrame material, Cover fabric, Certificates ... 3 layer shell inner decorative lining Polyester. Exterior c UV resistant waterproof canvas or Wool felt. The wool-felt is installed under canvas as insulation Frame is hardwood or steel and wood in L series. Lattice walls are constructed from wood pine. Roof ring and rafters are solid hardwood. Warranty is one year Lifespan is 20 plus with proper care.