Steve Honey
Hi I would first ensure you have no blockages, if the issue is just with the shower, i would remove the insert and pour water down the drain and use something every flexible such as a wire and check for local blockages. before adapting any pipework you would need the advise it there are currently any know vent pipes. A normal shower tray outlet is normally a trap as the insert which come with most traps forces the water down, round and up the back of the insert a little and out of the drain. there is normally a small bit of water at the bottom creating the air trap. i would need to know if water is running fine from all outlets in the room such as sink, shower, bath and toilet. some very low shower trays in showers such as wetroom come with hepvo traps and they are good until a solid such as hair gets trapped, this prevents the material from sealing and then you have the same issue. Thanks steve HBF Services
