Polyester is usually priced lower than Sunbrella and similar or higher than Tyvek, depending on the manufacturer. Some RV covers employ a high-quality material such as Tyvek only on the roof, using something less expensive on the sides to keep costs lower. Full Tyvek covers may be as expensive as Sunbrella or less expensive than Polyester depending on the manufacturer and what percentage of the cover is in fact Tyvek.
