In Waterproof Membrane Construction, Which Parts Are Prone To Leakage

Waterproof membrane bubbling

Phenomenon

Bubbling is found after the coil is pasted, usually from small to large. With the increase of temperature, the number and size of bubbles increase.

Cause Analysis

The base layer is not dry, the surface is not cleaned, water vapor penetrates into the bottom of the waterproof layer, the base layer is not coated with the base treatment agent, the adhesive does not match the material of the membrane, the coating is uneven, and the air on the floor is not excluded when the coil is applied , Some exhaust slots are blocked.

Prevention

The base layer must be dry and can only be paved after passing the simple inspection method. The base layer should be cleaned, and the base treatment agent and adhesive selected should match the material of the membrane, and can be used only after passing the test. After the brushed base treatment agent is dried, apply the adhesive. When laying the rolls, the air underneath must be wiped and compacted. Can also use sticky, point sticky, empty paving methods to ensure that the exhaust duct is unblocked.

waterproofing membrane crack

Phenomenon

Leakage along the ends of prefabricated roof slabs, joint cracks, and irregular cracks

Cause Analysis

Blindly use a low elongation coil, and the plate ends and node details have not been made with additional buffer layers and reinforcement layers. The construction method is wrong, such as pulling too tight when laying the coil.

Prevention

Ⅰ. Selection of coils with large elongation and durability over 15 years

Ⅱ. A buffer layer is provided at the end seam of the prefabricated roof panel, and the width of the dry-laid coil is 300mm. It should not be pulled too tightly when coiling. In summer, relax after construction.

Ⅲ. When the waterproof membrane has cracks, cut along the cracks with a cutter. If there is no separation seam in the base layer, cut it. The width of the seam is 20mm. A flexible sealing paste is embedded in the seam. A 200mm wide coil strip is laid along the seam as a buffer layer, and a 350mm wide coil is fully waterproof.