2. Have there been changes to the original drainage?

Misconnections can happen when any property is extended or altered. Many people make improvements to their properties and when they do any new drainage may well be misconnected. This might be wastewater drainage connected into a clean sewer or clean roof drainage into a foul sewer. You can often tell if a property has been extended by changes to brickwork, roof tiles or just having a different style or design.

Even if the construction work has been done by a builder there can still be misconnections. Sometimes the only way to tell is by dye testing or a drainage survey. A good way to check is to look at original roof down pipe and where these run and consider whether any alterations could have been misconnected.