Back on topic
Absolutely @macten
There's a firm argument in its necessity in the floor of a wet area and 4" up the walls. But as to whether it's a must have all the way up to ceiling, with your 600x600 porcelain tiles. No
As someone says, there's key areas which are common to Water ingress.
Sometimes OTT belt and braces have a habit of becoming the norm!
Absolutely @macten
There's a firm argument in its necessity in the floor of a wet area and 4" up the walls. But as to whether it's a must have all the way up to ceiling, with your 600x600 porcelain tiles. No
As someone says, there's key areas which are common to Water ingress.
Sometimes OTT belt and braces have a habit of becoming the norm!