What type of sealent do I need for an upstaires wet room?

rule no 1 ..never have a shower on first floor ....they will allways be a pain ...now you will need to remove all Old sealants in shower -room and reseal ...use a good quality bathroom sealant with a built in fungicide ...dow-corning are best ...ensure all surfaces are clean and dry before applying ..never use ordinary silicone in a bathroom