UNDERLAY BASE 900

SBS-modified bitumen glass fiber reinforced underlay membrane for pitched roofs with mechanical fixation

SBS-modified bitumen membrane UNDERLAY BASE 900 is used as an underlayment for roofing shingles in systems of pitched roofs with mechanical fixation (nailing). The material is installed on the continuous rigid wood decking (OSB-3, plywood, tongue or groove planks). Cannot be used in zones of valleys and eaves as these areas are most prone to leakages and require the application of self-adhesive membrane ULRAFLEX SA.

Waterproofing material UNDERLAY BASE 900 has the following advantages:

  • Both sides of the material are covered with fine-grained sand that prevents applicators from slipping from the pitched roof;
  • The light weight of the membrane makes application on the roof slope easier and safer;
  • The high-quality polymer-bitumen compound has the property of self-healing, which grants absolute tightness in places of nail penetration.

Product technical data

PROPERTIES PERFORMANCE
Mass per unit area, kg/m2 0.9±0.1
Length x width, m 20 x 1
Flexibility at low temperature, °C ≤-5
Flow resistance at elevated temperature, °C ≥95
Elongation L / T, % 4±2 / 4±2
Tensile strength L / T, N/50 mm 400±100 / 400±100
Tear resistance L / T, N 100±50 / 100±50
Reinforcement type glass fiber
Protective covering type on the top fine-grained sand
Protective covering type on the bottom fine-grained sand