Drain has a "floor"

[bsnalex]

I'll try to explain this as best I can, plumbing (and most diy) isn't my strong suit. We've lived in our house around 5 months now. Early 90's bryant homes. The ensuite bathroom has a shower cubicle with a drain in the corner. On top of the drain is one of those chrome dome discs that sits over the drain hole, allowing the water to flow under the disc.

Over the last few weeks I've noticed water quickly makes its way up and over the disc, until I'm eventually standing in almost an inch of water. The shower tray itself is only around 2 inches deep until it meets the glass door. This usually happens within 90 seconds. Once I start washing, the suds only exacerbate the problem as they're thick and blockade the sides of the drain cover. Once I turn the shower off, it eventually (within 2 minutes) drains out.

I removed the drain cover today and saw that water is standing in the drain pipe up to the opening of the drain. Water flowing slowly into the drain pushes it down, but water flowing quickly backs up into the shower, and then eventually drains out. I stuck my finger to see if I could feel a block near the drain opening, but found about two inches into the drain, my finger just hit what felt like a PVC floor, rather than going into a PVC bend. There is a small gap (around a half inch) for water to flow out of, into I would presume the main drain system.

Is this normal? I would have thought the drain was similar to a bathtub in that it flows out, into a pipe and then straight into the drain system. Can anyone offer advice on how to increase the drain flow? Particularly as I'm going to be investing in a megaflow/unvented system in the near future (currently on combi), so the flow rate will increase.

Thanks

 

[muggles]

The PVC floor with the holes in it that lets the water out is a removable section. Pull straight upwards and it should come out. You'll then be able to pour done drain cleaner into the drain - it's probably blocked with hair and soap

 

[bsnalex]

That was great advice, thanks. I pulled the top of the drain out as suggested. It appears to then sit in a sort of cup that gathers any silt, hair, gunk, etc. The reason why the water appears to stand in the drain is because the "cup" drains at the top, so the water has to go back up to drain back down to the main drain. So obviously once the water isn't clearing that hole at the top of the cup, it will stand. I managed to disassemble the whole thing, scrub it with bleach and send some drain cleaner into the main drain. Works a lot better now.

 

[Madrab]

That cup creates the water seal of the shower waste. As the cup fills up the top normally has a dip tube that then sits in the water creating the seal. Take the top and cup out and get some hot water out of the kettle, pour some cleaner down and then hot water immediately after, keep doing that until it drains quicker. If the shower gets a lot of use then do that once a month.