MEP Layout in Hotel Kitchen Areas and Decorative Waterproofing and Fire Protection Requirements
I am decorative specialist Chris Zhang. The MEP layout and decorative waterproofing and fire protection requirements for hotel kitchen areas are among the highest-risk and most professionally cross-disciplinary aspects of hotel design, directly affecting operational safety, hygiene and epidemic prevention, and fire code compliance. In multiple five-star hotel projects, I have encountered rework due to pipeline conflicts or substandard waterproofing in kitchen areas, so it is essential to strictly follow GB 50222 "Code for Fire Prevention in Design of Interior Decoration of Buildings," GB 50016 "Code for Fire Protection Design of Buildings," GB 50209 "Code for Acceptance of Construction Quality of Building Ground," and JGJ 64 "Standard for Design of Catering Buildings," among other codes.
**I. MEP Layout and Decorative Coordination Interface:**
Kitchen areas have dense MEP pipelines, including kitchen exhaust, fresh air, water supply and drainage, gas, electrical, and fire protection systems. Decorative ceilings must reserve access openings and interfaces for these systems.
- **Kitchen exhaust system:** According to Article 4.0.4 of GB 50222, kitchen exhaust ducts shall use non-combustible materials and maintain a clearance of at least 150 mm from the decorative ceiling to avoid thermal bridge effects. I once handled a case where the exhaust duct was installed directly against the ceiling, causing the gypsum board to deform and crack. The correct approach is: install independent fireproof wrapping within the ceiling, apply 50 mm thick rock wool to the outer surface of the duct, wrap with aluminum foil, use light steel keels (not wood keels) for the ceiling framing, and use 12 mm thick fire-rated gypsum board.
- **Water supply/drainage and gas:** Kitchen floors shall be provided with drainage channels or floor drains, and decorative floor tiles shall be sloped toward drainage points (slope ≥ 2%). Gas pipelines shall not be concealed within decorative finishes; they must be surface-mounted or installed in dedicated pipe shafts, and valve locations shall be provided with access doors (size ≥ 400x400 mm). In a hotel renovation, I once encountered a situation where the gas valve was concealed by the ceiling, requiring ceiling removal for maintenance; it was later changed to an openable access panel below the ceiling.
- **Electrical points:** Kitchen lighting fixtures shall be moisture-proof and oil-proof (IP54 or above), and the horizontal distance from switches and sockets to stoves shall be ≥ 1.0 m. Before tiling decorative walls, junction box positions shall be reserved to avoid later drilling that damages the waterproofing layer.
**II. Decorative Waterproofing Requirements:**
Floors and walls in kitchen areas must be waterproofed. According to Article 4.9.3 of GB 50209, the kitchen floor waterproofing layer shall turn up onto walls ≥ 300 mm, and walls behind vegetable washing areas and stoves shall be waterproofed to a height of 1.2 m.
- **Floor construction:** Typical approach: structural floor slab → cement mortar leveling → polyurethane waterproof coating (2 mm thick) → cement mortar protective layer → anti-slip floor tiles (water absorption ≤ 3%). I have encountered situations where tiles were laid directly without a ponding test on the waterproofing layer, causing leakage to the floor below. The correct procedure is: after completing the waterproofing layer, conduct a 24-hour ponding test, confirm no leakage, then lay tiles.
- **Wall construction:** Kitchen walls are typically tiled (glazed tiles or homogeneous tiles), and the substrate shall be plastered with waterproof mortar. In pipeline-dense areas (such as near drainage pipes), cement-based waterproof coating shall be applied around pipe roots to prevent water from penetrating through pipeline gaps.
**III. Fire Protection Requirements:**
According to Article 3.0.2 and Article 4.0.5 of GB 50222, decorative materials in kitchen areas have the highest combustion performance rating requirements:
- **Ceiling:** Class A materials must be used (such as light steel keel + fire-rated gypsum board, aluminum ceiling panels). Mineral wool boards or PVC panels (Class B1) are strictly prohibited.
- **Walls:** Within 1.5 m of stoves, wall finishes shall use Class A materials (such as tiles, stainless steel panels). I once saw a hotel kitchen with wallpaper behind the stove, which was ordered by the fire department to be rectified and later changed to a stainless steel backsplash.
- **Floor:** Class A materials shall be used (such as tiles, terrazzo); carpets or rubber flooring shall not be used.
- **Other:** Kitchen doors shall be Class B fire doors and open in the evacuation direction. Where kitchen exhaust ducts penetrate fire compartments, fire dampers (fusible at 70℃) shall be installed, and the gaps around ducts shall be sealed with firestop putty.
**IV. Practical Engineering Case:**
In a five-star hotel kitchen renovation, the original ceiling design used aluminum panels (Class A), but exhaust duct access openings were not considered, requiring aluminum panels to be cut later. I recommended installing 500x500 mm aluminum alloy access panels at each duct joint, lined with fireproof rock wool. Meanwhile, the floor waterproofing layer used acrylic coating (oil-resistant), anti-slip floor tiles were laid after the ponding test, and tile joints were filled with epoxy resin (mold-proof). All MEP pipeline wall penetrations were sealed with firestop putty and marked with fire protection labels. The project ultimately passed fire acceptance inspection.
**Summary:** The MEP layout and decorative waterproofing and fire protection for hotel kitchen areas require multi-disciplinary coordination at the drawing stage, with key control over fireproof wrapping of exhaust ducts, waterproofing turn-up height, combustion class of decorative materials, and access opening provisions. Any negligence in details may lead to operational interruption or safety hazards.
The above are reference opinions. Actual project conditions still need to be further comprehensively evaluated and implemented in combination with specific working conditions, site conditions, and other factors.