How to Move the Toilet Drain Outlet

There are several methods for moving the toilet drain outlet, and you can choose the appropriate one based on actual needs and conditions:

I. Using a Drain Offset (Suitable for minor adjustments within 15cm)

A drain offset is a plastic pipe with a slope used to connect the toilet's drainage outlet to the main pipe, only suitable for short-distance adjustments (≤15cm). When installing, note the following:

1. Timing of Construction: It must be completed before tiling to avoid damaging the ground structure later.
2. Slope Control: The greater the slope, the smoother the drainage and the less odor, but the ground will have a "low in front, high in back" tilt, so communicate with the tiler in advance to adjust the tile-laying method.
3. Length Selection: Drain offsets come in different specifications. Measure the center distance between the original drainage outlet and the downpipe, and prioritize choosing a slightly longer model to avoid installation difficulties due to insufficient length.

II. Raising the Ground + Installing a Water Trap (Suitable for moves over 15cm)

When the move distance exceeds 15cm, raising the ground is required to achieve pipe bending:

1. Height Requirement: The standard drainage pipe diameter is 110mm, and the ground must be raised by at least 120mm (including the cement mortar leveling layer, it is recommended to raise it by 15cm in practice) to ensure the pipe bend does not get clogged.
2. Water Trap Configuration: A water trap must be installed and the water seal height must be maintained at ≥50mm to prevent odor backflow.
3. Ground Treatment: It is recommended to lay sloped tiles in the raised area, which is conducive to drainage and reduces visual abruptness; if a threshold stone needs to be installed at the doorway, pre-embed expansion joints in advance to avoid deformation of the door frame due to thermal expansion and contraction.

III. Cutting a Hole in the Floor Slab (Requires consent from the downstairs occupant and structural permission)

If the floor's load-bearing and waterproofing conditions are met, a 110mm round hole can be cut in the floor slab above the original drainage pipe, and the new pipe can be laid along the wall to achieve zero ground raising:

1. Advantages: No slope limitation, aesthetically pleasing space, and high drainage efficiency.
2. Limitations: Consent from the downstairs occupant is required, and the floor slab structure must be sturdy (such as a reinforced concrete floor slab).
3. Construction Points: It must be positioned by a professional plumber, and the error must be controlled within 1cm to avoid hitting the steel bars and leaving safety hazards.

IV. Tool and Accessory Preparation

1. Tools for Modifying 110 Pipes: Prepare downpipes, 110 pipe gaskets (remove the original gaskets for iron pipes), upper drainage 110 elbows, and other accessories.
2. Renovation Plan for Old Houses: A combination of 110 flat pipes + 90 round pipes can be used to flexibly adjust the pipe direction.

Precautions: All construction must comply with building codes. When structural modifications are involved, be sure to consult the property management or a professional engineer to ensure safety and compliance.