Rainy or sunny weather, aerogels always insulate. With outdoor installations the rain will not stop work, because Aspen aerogels are hydrofobic and do not need to be covered.

Aspen Aerogels’ blanket products are chemically treated to repel water at the molecular level. This treatment process keeps water from penetrating or condensing within the pore structure under demanding conditions - even after submersion in seawater for 6 weeks! The test was done with Spaceloft 2200, and its thermal properties were tested afterwards with ASTM C177 test. No change in thermal properties was noticed afterwards. Aspen's patented production proces adds hydrophobicity to all their materials.

While many insulation material possess good MCT properties few can hold out liquid water allowing the ability to perform the inverted cup portion of the ASTM E 96 test.

Aspen's blankets have a high moisture transmission rate. ASTM E96 Standart Test Methods for Water Vapor Transmission confirm that the moisture transmission rate is comparable to commonly used WWR fabrics. The table below compares Spaceloft AR 3191 to 26 commercial available breatable waterproff fabric packages.