How to Move a Toilet Sewage Riser

Moving a toilet sewage riser requires selecting an appropriate method based on the displacement distance and requirements, and strictly adhering to construction specifications. The specific steps are as follows:

I. Pre-construction Preparation

1. On-site Survey and Plan Confirmation

   • Requirement Confirmation: Clarify with the homeowner the new bathroom layout, space requirements, and special fixture installation needs, and measure dimensions.
   • Pipe Assessment: Check the original riser material (e.g., replace aging cast iron pipes with PVC pipes) and size, and confirm the displacement direction and distance (recommended not to exceed 30 centimeters, as longer distances increase drainage resistance and risk clogging).
   • Compliance Confirmation: Riser displacement requires drilling holes in the floor slab, which requires consent from the downstairs homeowner and notification to the property management for a construction permit. Use a pipe detector to confirm that the drilling location has no embedded wires or pipes and avoids load-bearing wall structures.
   • Drainage Slope Calculation: The standard slope for a 110 drainage riser is three to five thousandths (a drop of 3-5 millimeters per meter). Calculate the trenching height in advance to ensure smooth drainage without water accumulation.

2. Material and Tool Preparation

   • Use national standard 110mm PVC drainage risers with a wall thickness of 3.2 millimeters, and ensure accessories meet quality standards.

II. Specific Displacement Methods

1. Displacement Device (Suitable for short-distance displacement of 10-30 centimeters)

   • Principle: Use an S-shaped flat pipe to bypass floor reinforcement, ensuring drainage through slope design.
   • Installation Points:
     • Reserve a 1-2% drainage slope (a drop of 1-2 centimeters per meter);
     • The toilet base needs to be raised by 2-3 centimeters to avoid two consecutive 90-degree bends;
     • The flat pipe length should not exceed 30 centimeters to prevent clogging.

2. Same-floor Drainage (Suitable for long-distance displacement over 50 centimeters)

   • Principle: Chisel away the original waterproof layer, rearrange the 110mm main drainage pipe, and compensate for height differences by raising the floor.
   • Construction Points:
     • Adopt stepped or overall floor raising of 5-8 centimeters;
     • The pipe trench requires double-layer waterproofing and a 48-hour or longer closed-water test;
     • Suitable for sunken bathrooms or renovatable spaces.

3. Wall-mounted Drainage (Suitable for space-saving needs)

   • Principle: Bury the drainage pipe in the wall, paired with a special wall-mounted toilet, allowing for storage cabinets or niches behind it.
   • Construction Points:
     • Reinforce the load-bearing wall to support the toilet weight;
     • Suitable for modern minimalist bathrooms, with no dead corners and aesthetic appeal.

Precautions: All displacement operations must be carried out by professionals to ensure compliance with building codes, avoiding structural damage or leakage issues.