摘要 |
<p>A method of weather-proofing surfaces, particularly concrete roofs, is described wherein first applied is an inner layer of a soft asphalt (bitumen) having a softening point of 100 DEG -140 DEG F. and including reinforcing fibers, and then an overlying layer of an asphalt-saturated-felt. In one preferred example, the overlying layer is a glass-fiber mat saturated with a hard air-blown asphalt having a softening point of at least 180 DEG F.; and in a second described example, it is paper saturated with soft (non-blown) asphalt and coated on its outer faces with the hard air-blown asphalt. The combination of the soft asphalt inner layer and the asphalt-saturated-felt outer layer has been found to produce a barrier impermeable to water travelling inwardly, but permeable to vapor travelling outwardly thereby avoiding the formation of blisters. This combination has been further found to be suitable for surfaces having extremely high slopes, even perfectly vertical surfaces, without the need for mechanical fastening devices.</p> |