Common Do’s and Don’ts
QWhat are the main pitfalls to avoid when tanking?
Protecting the area / seal around the gully is very important. Note the differences between the wrong and right images. Key mistakes are illustrated with arrows. The blue arrows indicate where the outlet sleeve must have been cut in three places. The red arrows indicate that the outlet sleeve has bubbled and there’s air underneath, plus the meshed perimeter edge has not been bedded in the tanking compound. Additionally, the temporary cover plate has not been used to protect the gully from dust and debris.
On the top image, the’right’ image shows the outlet sleeve has been properly bedded down and allowed to dry before fitting the clamping ring to the gully. The sleeve is torte with no air bubbles, preventing any easy penetration.
In the second image, the red arrows in the ‘wrong’ image point to seams which should be covered by the tanking tape. The arrow on the left shows how the tape does not run along the whole floor wall intersection. The green arrow with small blue circle shows the screws protruding above the floor deck. Screws should be countersunk flush with the top surface. The ‘right’ image shows a completely tanked wet room ready for tiling. The surface is smooth with all tanking tape overlapped, creating a full seal of the wet room floor. In this case the complete wall has been tanked for extra security, although OTL generally recommended tanking to a minimum 1000mm up the walls in the shower area.
In the last image, the red arrow in the ‘wrong’ image shows where the floor levels are uneven, which can affect the gradient making tiling more difficult. The existing floor outside the showering area should be level with the 24mm former. The blue arrow in the ‘right’ image shows the floor is completely even underneath the tanking tape.