Old House Renovation: Kitchen Mobile Toilet

In the renovation of old houses, the relocation of the kitchen mobile toilet (kitchen and bathroom relocation) requires careful planning. It must meet conditions such as structural safety, regulatory compliance, sewage discharge feasibility, and neighbor coordination, and a decision should be made after comprehensively evaluating spatial benefits and technical solutions.

I. Decision-making Red Lines That Must Be Met

1. Structural Safety: The new location must not damage load-bearing walls or structural beams and columns; otherwise, construction cannot proceed.
2. Regulatory Compliance: The new bathroom must not be directly above the kitchen downstairs, which violates the mandatory requirements of the "Residential Design Code."
3. Sewage Discharge Feasibility: The toilet must be connected to the nearest 110mm main sewage pipe. If the main riser cannot be connected, the renovation risk is extremely high.
4. Neighbor Coordination: When there is a change in the drainage path, written consent from the downstairs neighbor is required to avoid disputes.

II. Spatial Benefit Evaluation Criteria

It is necessary to quantitatively compare the core experience indicators before and after the renovation. Renovation is recommended only when at least two indicators improve by more than 50% and the total cost is controllable:

• Movement Optimization: For example, the average daily number of steps is reduced from 28 to 16 (integrated dining and kitchen).
• Lighting Improvement: The duration of natural lighting increases from ≤2 hours to ≥5 hours (south-facing windows).
• Storage Enhancement: The effective storage area increases from 1.2 square meters to 3.5 square meters (U-shaped floor cabinets + tall cabinets).
• Function Upgrade: For example, upgrading from no wet-dry separation to a glass partition + independent shower area.

III. Technical Implementation Solutions

1. Drainage Renovation:
   • Raised Floor Method: For old houses with a floor height of ≥2.6m, a 15–20cm platform can be built to hide the pipes, and a gentle slope transition (slope ≤1:20) is required.
   • Wall-mounted Displacement Device: Suitable for minor position adjustments, but cast-iron old pipe connections are prone to leakage and odor risks.
   • Sewage Lifting Pump: Used for long-distance or upward drainage (such as in basements). It is necessary to choose a quiet model with a cutting blade (IP68 protection) and reserve a maintenance port.
2. Water Supply and Gas:
   • The water supply uses PPR pipes for hot-melt connections, runs along the ceiling instead of the floor, and is pressure-tested at 0.8MPa for 30 minutes without pressure drop.
   • Gas pipelines are prohibited from being privately modified and must be installed by the gas company.
3. Waterproofing and Hidden Works:
   • The wall waterproofing in the shower area should be ≥1.8m, and a closed-water test should be carried out for 48 hours.
   • After the completion of water and electricity works, image data should be retained for easy maintenance in the later stage.

IV. Cost and Construction Period Reference

The cost of demolition and restoration is approximately 2000 yuan (including garbage removal). The cost of new waterproofing and drainage renovation needs to be evaluated according to the specific plan. It is recommended to entrust a professional team for construction, focusing on details such as drainage slope and waterproof closed-water tests to reduce the risk of later use.