Blocked showertray waste

[Connor Williams]

Hello, I have a blocked shower tray.
The whb waste is tee'd into it as every time you drain the whb the water bubbles up through the showertray waste and then doesnt drain.
I cant get access to the wastepipes as they are boxed in, nor can I remove the showertray trap as it is under the floor.
I have poured down a very strong drain cleaner and tried plunging, is there any other way of clearing the blockage without having to take out the showertray and boxing, any kind of drain rod that could be recommended?
Many thanks for any help!

All the best,
Connor

 

[Phil]

Does the shower tray waste have a removable grate for cleaning purposes?

On new installations I always run both wastes seperatly, it is the best way.

Have you tried caustic soda? Read the label.