Non-pressure PVC-U systems manufactured by SKOPLAST are intended for underground drainage and sewage systems outside building structures. Our pipes are manufactured in two variants: with a foam and solid-core wall. We also manufacture pipes with an elongated socket for areas affected by mining activities. Non-pressure underground piping systems for drainage and sewage systems are designed to transport wastewater at temperatures up to 45° for continuous flow and up to 60° for emergency (short-term) flow. SN2 pipes can be used in areas without heavy traffic: pavements, green areas. SN4 type pipes can be used in areas with low traffic. SN8 pipes can be used in areas with heavy traffic and industrial areas. Strength calculations and technical considerations determine whether individual pipe types can be used.