DESCRIPTION
Permavent use the very latest technology from the medical industry to encapsulate the highest grade hydrophobic film inside the very highest quality spunbond polypropylene layers. Unlike other companies, who simply stick the different layers together, Permavent membranes are manufactured in a single process that greatly improves the quality and integrity of our membranes. This 3 in 1 process means that Permavent offer the best performing breather membranes in their class with superior strength, breathability, flexibility and durability.
Permavent-ECO is also fully certified under the CE having been tested and certified by independent European laboratories and is only manufactured under the strictest ISO requirements.
REQUIREMENTS OF BS 5534 ANNEX A FOR WIND UPLIFT
| Geographical wind zone | Design wind pressure, Pu, for underlay (N/m2) |
| Well sealed ceiling (e.g. standard domestic application) | Minimum requirement |
| 5 | 1600 |
| 4 | 1330 |
| 3 | 1150 |
| 2 | 975 |
| 1 | 820 |
| Not sealed or non-ceiling (e.g. garage or warehouse) | 1900 |
| Not sealed or non-ceiling in addition to permanent structural opening (e.g. car port or open store) | 2350 |
PHYSICAL PROPERTIES
| Weight, g/m2 | 90 |
| Water tightness, class | w1 |
| Water vapour transmission (sd),m | 0.02 |
| Maximum tensile force (MD), N/50mm | 200 |
| Maximum tensile force (CD), N/50mm | 150 |
| Elongation at max. tensile force (MD), % | 65 |
| Elongation at max. tensile force (CD), % | 55 |
| Resistance to tearing MD (nail shank), N | 100 |
| Resistance to tearing CD (nail shank), N | 90 |
PERMAVENT APEX WIND UPLIFT RESULTS
| Batten gauge | Declared Wind Uplift Resistance, PD (N/m2) | Zone Suitability |
| ?345 mm (maximum gauge, large format tiles) | Taped lap: 1539 | 1 to 4 (All aplications) |
| Batten restrained lap: not test | - | |
| ?250mm (600mm slates) | Taped lap: >2500 | 1 to 5 (All aplications) |
| Batten restrained lap: 1510 | 1 to 4 (All aplications) |
