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Hi, could any members point me in the right direction please want to do a under over waterproofing on my shower base, during the pour, forgot to put fall in the rebate,is there some product I could use that will bond to the substrate and give me good fall for the under
Under screed waterproofing,any help would be greatly appreciated
Cheers
Welcome to the Bunnings Workshop community @saundersmob. It's fantastic to have you join us, and many thanks for your question about creating fall in a shower.
It sounds like you'd need something like Dunlop 20kg General Purpose Construction Grout, and you'll need to use the Dunlop 4L Multipurpose Primer to ensure it bonds sufficiently to the current cement. The area you'll be adding falls to must be cleaned well before priming.
The Dunlop construction grout is suitable for layers from 10-100mm. Let me know if you need to do feather edging or less than 10mm.
Please let me know if you have any questions.
Mitchell
Hi @saundersmob,
I've gone back to Dunlop to work through this with their technical assistance. The advice I've now received from a tiler is that it would be better to screed the area with standard sand and cement. They advised that to ensure the sand and cement adheres to the existing concrete, it's important to create a wet cement slurry over the concrete first. Wet the area, sprinkle cement over it, and broom it in to form a paste. Whilst it is still wet (so it is best to mix your sand and cement up prior and have it waiting), apply your sand and cement over the area and work it with a trowel to achieve your fall.
The cement slurry must be wet, so it's a wet-on-wet mixture. This allows a connection to form between the slab, cement, and sand and cement.
Please let me know if you have any questions.
Mitchell
