To ensure the drainage system is compatible with the Sika-Trocal®/Sikaplan® roofing system, and provides effective drainage, high quality injection moulded gravity fed rainwater outlets and scuppers can be used. Where alternative rainwater outlets or scuppers are used compatibility with the Sika-Trocal®/Sikaplan® membrane must be checked, the outlets must also provide an effective sealing method.

Where Sika-Trocal®/Sikaplan® rainwater outlets are used the Sika-Trocal®/Sikaplan® membrane is simply welded to the injection moulded flange incorporated into the body.