I have been using TCNA B431-20 for shower receptors for years, although I am beginning to run into shower designs that require a topical system based on material availability. I am planning a larger shower than I’m used to; is it acceptable to combine TCNA F141-20 and F145-20 in the same application? I’ve attached a detail of the specific project for clarification.
Thank you for contacting the National Tile Contractors Association. It appears the entire bathroom requires waterproofing and slope. If you are looking for surface-applied waterproofing shower methods you have two options: B421 and B422. You have specified a Noble product for surface-applied waterproofing. They have drain flashing that would connect to a conventional clamping ring drain and could be done in accordance to TCNA method B421. Please investigate this as an option.
– NTCA Technical Team