Hi,
Every time I run a bath in our house, water constantly flows through the overflow pipe and into our garden at the back. To stop this I have to get into the attic and uncover the water tank to pull the ball cock back up. This seems to stop the flow once the excess water has run out the pipe but I would like to know if you know why this happens every time?
It has only recently started but I do not want to have to go in the attic every time this happens or wade through a water logged garden!

Thanks in advance.

Dan

It seems as if you are describing a tub but then are talking about a toilet with a garden behind it. Could you be more clear?