These two models are built on a white PVC frame covered with a 21-ounce vinyl canvas that remains installed on the frame year round. This mould-treated canvas has a lifespan of 15 to 18 years and requires no maintenance. The vinyl panels are heat-sealed together to make this canvas even more efficient. If windows have been added, we recommend cleaning them with a mild, non-abrasive soap diluted in a large quantity of water.