A Broken Building and a Mystery

When I was out exploring last weekend, I discovered this beautiful broken down building. It is amazing and I plan to go back out and do more shooting. The mystery is what was this building used for? Its made of brick so I doubt it was built for a tool shed. Its too small to have been a house yet it has plumming. Its in the middle of a field next to a sawmill but I'm sure the building came before the mill.

Maybe I'll try to sneak into the field and get a better look next time.