What type of piping should be used for all sewer fittings beginning at the house?

Using Schedule 40 PVC with a minimum of 4-inch diameter for all sewer fittings beginning at the house is essential for several reasons. Schedule 40 PVC piping is designed for higher pressure and is generally more durable than Schedule 20 or Schedule 30, making it more suitable for the demands of sewer systems where the flow conditions can vary and may include solids.

The 4-inch diameter requirement is important too, as this size is standard for residential sewer drains, ensuring that it can adequately handle the volume of wastewater generated by a household while reducing the risk of clogs. Larger diameters become essential in sewer systems to facilitate smoother flow and accommodate potential blockages.

In comparison, other options do not meet industry standards and regulations for sewer systems, potentially causing problems like inadequate flow, increased risk of backflow, and inability to handle the waste materials typically found in sewage.