HDPE knitted sails and Textilene can block up to ~98% UV while still passing rain. PVC membranes block more heat and are waterproof.

Energy · 5 min · 2026-05-06

UV protection ratings for outdoor fabrics

UPF, openness factor and heat-sealed membranes — what each number means for skin and interiors.

Pick fabric for the job

Solution-dyed acrylic on awnings is UV stable through the fabric warranty. Screen fabrics are specified by openness (1–10%). Shade sails list UV block on the Vela page. Pool solar slats are about water temperature, not skin UPF.

Questions people ask

Does mesh block UV?: HDPE knitted sails and Textilene can block up to ~98% UV while still passing rain. PVC membranes block more heat and are waterproof.