TECHNOELAST K-MS 170/4000 is a polyester based Underlay saturated and coated with high quality SBS (Styrene-Butadiene-Styrene) modified bitumen. The membrane is protected with thermofusible film on its lower side and fine-grained sand on the upper side, making the membrane suitable for both Torch – On and Hot or Cold mastics application.
Materials can be used as underlays in built up waterproofing systems or as vapour barriers on new built or refurbished flat roofs as well as part of overlay systems to existing asphalt waterproofing. Not recommended for use as single ply waterproofing.

Membranes are applied by traditional Torch – On method onto previously prepared surface, clear of any debris or sharp projections, primers shall be used to prepare substrate for achieving most effective waterproofing longevity. The membranes should be heated carefully ensuring the complete melt of dispersible film as work proceeds. Side laps must be minimum 75mm with end laps at minimum of 100 mm. The subsequent cap sheet layer should be offset 300 mm from the underlay to avoid build up of overlaps.

Product technical data

 Length x width, m 10 x 1
 Thickness, mm -
 Mass per unit area, kg/m2 4.0 ± 0.20
 Reinforcement type polyester
 Elongation L / T, % 50/50±25
 Tensile strength L / T, N/50 mm 700/500±100
 Tear resistance L / T, N 180/180±30
 Flexibility at low temperature, °C ≤ -25
 Flow resistance at elevated temperature, °C ≥ 100
 Protective covering type on the top fine-grained sand
 Protective covering type on the bottom film