Key Points for Restaurant Kitchen Drainage Design

Restaurant kitchens use the most water. Blocked drains smell and hurt hygiene. What must drainage design get right? CHINENG explains.

Drainage design notes

1. Odor, rodent, and insect control: cover channels with traps; use screened floor drains; fit steel/copper rodent screens at sewer outlets with bars too tight for mice.

2. Provide floor drains in pantry and cold rooms (brass/stainless covers); put a drain trough at ice-machine fronts.

3. Channel depth is often limited (~300 mm sumps); width by flow; slope preferably >0.5%; length ideally <10 m.

4. Drop the kitchen slab ≥30 cm for channels; add a catch basket before the main drain.

5. Line channel sides with white tile or stainless; waterproof thoroughly.

6. Place stacks beside the heaviest fixtures without blocking work.

7. Oil separation: oily kitchen waste needs grease interceptors—preferably stainless units with baskets for solids.

8. Provide secondary grease treatment before municipal sewers; units may sit on floor or in the dropped slab.

9. Keep branch runs short to stacks or vent them.

10. Heat-resistant plastic in dropped slabs; cast iron elsewhere as required.

11. Open channels drain and clean easily but can smell; closed drains look cleaner and free equipment layout but clean harder.

Sewer detailing

1. Avoid undersized equipment wastes—prefer DN50–DN75; floor discharge clears faster.

2. Corrosion-resistant, anti-slip floors slope ~1% to open channels with rounded bottoms.

3. Leave capacity spare for future expansion—pipes are hard to enlarge later.

CHINENG offers free commercial kitchen design schemes on request.