Re: Sheddwellers. (The Extension).
If the water in the photo is at the low point of the trench where your services come into your shed, your plumber is on the right track. The water will run down to the lowest point.
Regards Bazza
Good to see another aussie metal shed. i had the same computer trouble, took a long time to get all my photos out of my old computer, but i saved them.
I will put some of mine on later. great looking house .
Bazza