3. Have there been any extensions or alterations, new bathrooms, toilets or kitchen installed?

Many people make improvements to their homes.  Changing bathrooms or kitchens, adding downstairs toilets or en suites are quite common alterations and can be relatively easy to do for a competent ‘DIYer’.  Often these changes may not even need building control approval.  Wastewater drainage can easily end up being connected to the nearest roof down pipe or convenient surface water drain.

Check your property to see if these types of alterations have been made and where any drainage goes to.  Often these types of misconnections can be very easy and cheap to correct by simply reconnecting into the right wastewater sewer.