Help please!

[block]

Hi guys.
A bit of guidance if you please. Yesterday the upstairs bathroom sink and bath started draining exceptionally slow. When draining the sink it backs up into the bath a bit. Toilet flushes fine and the donstairs sink appears fine. It would appear I have a blockage somewhere within the pipes at a point that I cant get to due to the pipes running in a boxed in corner covered with tiles both in the bathroom and kitchen.
Any ideas would be very much appreciated.
Thank you.
Crap 'diagram' of pipe network below!

I--------------------------------sink
I
I----------------------
I I
I I
I I
I bath
I
boxed in tiled corner where pipes 'disappear'.

 

[garrywhite]

Many things. Wastes partially blocked. Could be frozen somewhere along the pipe. Try running your hot for a while. If that doesnt work use a plunger on basin and bath plug holes(block the overflow with a flannel), if you can disconnect pipe work anywhere use a spring rod cleaner, if that fails try a drain cleaner. Read the label on the bottle with this one. Hope this helps.

 

[block]

Thank you Gary.

Put some drain cleaner in and left it for an hour, then poured in boiling water and after a fair bit of bubbling and gurgling it cleared. No wiser as to what the problem was but at least it is clear now.

Thanks for the response.