... it is not sensitive to temperature fluctuations. 2) Cushion,the fabric and sponge inside the cushions, they are all water proof ... just use 20 density which is bad. Further more,sunbrella fabric,which is famous and top quality,we can use them ... , France, Netherland, Switzerland, Argentina, Spain, USA, Mexico, UK, Rattan Furniture Sofa, Sofa Outdoor (RT-S0010) Rattan Sectional Sofa