Durability—Resistance to Damage from Substrate Cracking/Movement

Cracking of substrates is a common challenge for all waterproofing materials. Materials provide a solution to this issue in various ways. Liquid-applied materials bond to the substrate so that when a crack occurs the membrane must elongate the complete width of the crack. Single ply membranes that do not bond to the



Test Method

Cold Liquid-Applied

ASTM C 836

No cracking

Low temperature craek bridging. C 1305. Dynamic lest at -26"C {-15°F) with 3.2 mm (1/8 in.) opening


No leakage

ASTM C 1306 or D 5385, Hydrostatic test after extension over fixed crack at standard conditions with min. 1.6 mm (1/16 in.) opening

Hot Liquid-Applied


No eraeking, splitting, or loss of

Crack Bridging Capability,

adhesion over 3 mm erack

CAN/CGSB-37.50-M89. Dynamic test at -25n±2′,C with 3 mm opening

Single Ply Membranes

ASTM D 6134. Type I

300 %, min

elongation, Ultimate, ASTM D 412, Die C

9 MPa (1300 psi), min

Tensile strength, D412, Die C

ASTM D 6134, Type II

300%, min

Hlongation, Ultimate, ASTM D 412, Die C

8.3 MPa (1200 psi). min

Tensile strength, D 412, Dio C

CAN/CGSB-37.54-95, T^pe 4,

15 %

Elongation at break ASTM D 751.

Class C

Procedure A

35 kN/m

Breaking Strength, ASTM D 751, Procedure A

CAN/CGSB-37-GP-52M, Type 2,

200 % , min

Ultimate Elongation, ASTM D 412,

Class В

Die C

500 N. min.

Breaking Strength. ASTM D 751, Method A

substrate accommodate substrate cracking and movement by a combination of elongation (capacity to stretch) and tensile strength (resistance to breaking). Refer to Table 5 for a review of standards.

Liquid-applied materials have very similar test methods and acceptance criteria for low temperature crack bridging. The principle difference between the ASTM C 1305 and CAN/CGSB-37.50-M89 crack bridging tests is in the thickness of membrane test specimens; cold liquid-applied specimens are 1.52 mm (60 mils) thick and hot liquid-applied specimens are 3 mm (118 mils) thick.

A principle difference between the tests used for single ply membranes is the speed of extension. Test machines operate much slower for PVC (5 mm/min (0.2 in./min)) compared with the other single ply standards (500 mm/min (20 in./min)). Considering the intended use of the material, the slower speed of extension used for PVC seems appropriate.