Waterproof/fill void left after removing vanity

Hi David, photos will greatly assist!!!

Thanks Bart, I have added a few pictures now

Originally Posted by Bart1080

Hi David, photos will greatly assist!!!

Thanks Bart, I have added a few photos

A concrete or screed mix should be fine.


The rubber stuff looks to be old waterproofing??

In the 2nd & 3rd photo, is the blackness the rubber or moisture from the shower?



RE: waterproofing the new floor
1. If you've got an enclosed shower built to AS3740 standards, then the entire floor doesn't need to be waterproofed as per AS3740.
A consideration is how the shower/bathroom was originally built which is likely to be unknown....but the age may provide clues. ie: was it pre or post AS3740 Waterproofing of Domestic Areas

2. To correctly waterproof a floor to current standards, unless you know what the previous waterproofing product was and the new product is compatible, then there is no way to fully meet the AS3740 min requirements.
So to do it correctly, any decent licensed Waterproofer will tell you that to be covered by a warranty, they would need to do the whole bathroom if your bathroom design required that under AS3740

3. If your current shower isnt leaking and is enclosed, then there is no need to waterproof the floor your about to pour....with some assumptions on point 1.

Originally Posted by Bart1080

A concrete or screed mix should be fine.


The rubber stuff looks to be old waterproofing??

In the 2nd & 3rd photo, is the blackness the rubber or moisture from the shower?



RE: waterproofing the new floor
1. If you've got an enclosed shower built to AS3740 standards, then the entire floor doesn't need to be waterproofed as per AS3740.
A consideration is how the shower/bathroom was originally built which is likely to be unknown....but the age may provide clues. ie: was it pre or post AS3740 Waterproofing of Domestic Areas

2. To correctly waterproof a floor to current standards, unless you know what the previous waterproofing product was and the new product is compatible, then there is no way to fully meet the AS3740 min requirements.
So to do it correctly, any decent licensed Waterproofer will tell you that to be covered by a warranty, they would need to do the whole bathroom if your bathroom design required that under AS3740

3. If your current shower isnt leaking and is enclosed, then there is no need to waterproof the floor your about to pour....with some assumptions on point 1.

Many thanks for the detailed explanation Bart !
Yes, it is rubber from the old waterproofing. The silicone in the shower needs replacement so this is where the water were coming from into the vanity. No signs of leaks other than that.