Slow bathroom drainage.

Page may contain affiliate links. Please see terms for details.

Scaleyback

Veteran
Location
North Yorkshire
I have a similar problem with my shower draining away via a connection with the nearby sink drainage. I think the problem is insufficient 'fall-away so the 'gunge' tends to build up. First dismantle and then clean out the sink 'U'bend, rubber gloves are a good idea it can be pretty disgusting 'down there' Then, I like Tenkaykev above use a wet 'n'dry vacuum. First use the 'suck' from your bath/shower drainage to remove any water and hopefully 'gunge' Then from the same drainage point change your vacuum hose to the 'blow' hole. Remove the sink plug and drape a cloth over the entire sink. Blow from the bath/shower drainage point and gunge will 'explode' from your sink drain and it's overflow hole. I stress make sure you cover the entire sink or the blown out gunge will be sliding down your bathroom walls ! Always works for me.
 

slowmotion

Quite dreadful
Location
lost somewhere
My guess is that you have a partial blockage downstream of both the bath and the basin. Try this experiment....close off the bath waste (use a plug because pop-up wastes lift under back pressure) and seal off the bath overflow using duct tape. Then run a load of water through the basin and see if the basin drains away in a normal amount of time. If it doesn't, your partial blockage is somewhere downstream of the waste pipes from both the bath and the basin. Clearing out the bath and basin traps might help but the root of the problem may be elsewhere.
 

dicko

Guru
Location
Derbyshire
Faced with a similar problem I bought a twin pack of ‘Mr Muscle’ from Aldi and dispensed about a quarter of one bottle down the plug hole. I waited a couple of hours I then filled the bath a quarter full of cold water and pulled the plug. Soon the water was flowing out very quickly and no problems for seven months now.
 

Tenkaykev

Guru
Location
Poole
The very first one I cleared was indeed a fatberg left by a previous occupant of the house who had tipped a whole pan of fat down the sink after making chips.
The second one was not and cleared itself once a flow was estsblished.

One of the Beachfront cafés in Bournemouth would dispose of used cooking oil down the drain despite this being forbidden. We only discovered that they were doing this following a bit of detective work after the failure of the submersible pump on several occasions. The cooking oil was eating into the rubber cable supplying power to the pump and allowing the ingress of water.
 

oldwheels

Legendary Member
Location
Isle of Mull
One of the Beachfront cafés in Bournemouth would dispose of used cooking oil down the drain despite this being forbidden. We only discovered that they were doing this following a bit of detective work after the failure of the submersible pump on several occasions. The cooking oil was eating into the rubber cable supplying power to the pump and allowing the ingress of water.

A co- owner of a chip van here used it mixed with diesel in an old pickup he used. You could smell him coming if the wind was in the right direction. :laugh:
 

Fastpedaller

Über Member
Plumber here. DON'T dismantle the pipes...... you'll likely cause a lot of leaks. Use a plunger, but the key thing here is to block the overflow otherwise the pressure will just disappear via the overflow. You'll probably need to do the same with the plug and overflow on the basin, otherwise the pressure may go there. There are 'super plungers' with a handle (like a big diameter bike pump) so you can suck up water and blow that down. Air had limited effect as it compresses, so unable to move a blockage that water will.
Fill the bath to a few inches, and get your plunger in place. Let some water go down the plughole and plunge away. If all you efforts fail it's worth using some drain cleaner or caustic soda - pour it down and leave it for at least an hour and then do the above again. Careful with the chemicals - don't splash into eyes etc. Whatever you do, DON'T dismantle anything, and DON'T stick wiggly, curly things down the waste - i've seen so much unnecessary damage and leaks - indeed I had to sort one out yesterday!
 

Dogtrousers

Kilometre nibbler
DON'T stick wiggly, curly things down the waste -
I had one of those, a little mini drain rod I got off the internet. I shoved it down the sink ... the brush bit of it immediately came off and joined the other gunk down there! :laugh:

Fortunately the problem was solved with some drain unblocker stuff. The little brush head is now on a picturesque beach somewhere.
 
Last edited:
OP
OP
Salty seadog

Salty seadog

Space Cadet...(3rd Class...)
Plumber here. DON'T dismantle the pipes...... you'll likely cause a lot of leaks. Use a plunger, but the key thing here is to block the overflow otherwise the pressure will just disappear via the overflow. You'll probably need to do the same with the plug and overflow on the basin, otherwise the pressure may go there. There are 'super plungers' with a handle (like a big diameter bike pump) so you can suck up water and blow that down. Air had limited effect as it compresses, so unable to move a blockage that water will.
Fill the bath to a few inches, and get your plunger in place. Let some water go down the plughole and plunge away. If all you efforts fail it's worth using some drain cleaner or caustic soda - pour it down and leave it for at least an hour and then do the above again. Careful with the chemicals - don't splash into eyes etc. Whatever you do, DON'T dismantle anything, and DON'T stick wiggly, curly things down the waste - i've seen so much unnecessary damage and leaks - indeed I had to sort one out yesterday!

Brilliant, thank you, I've just stuck some Mr muscle gel down there. Will get onto the plunger plan too once I can get it back off my sister
 

lazybloke

Priest of the cult of Chris Rea
Location
Leafy Surrey
Considering how much untreated waste water ends up in rivers , i wish folk weren't so quick to reach for chemicals.

Out of sight, out of mind?
 
Top Bottom