The plan
Illustrative example. Not a real job or customer.
Owners of a 1970s slab home in Fullerton want to remove the wall sink and add an island with a sink, disposal and dishwasher. The old kitchen drain has clogged twice in recent years.
- They ask a licensed plumber to camera the existing kitchen drain before design is final.
- The camera shows rough cast iron and a sag near the old sink location.
- The plumber explains that an island sink needs a planned drain route under the slab and a venting method suited to an island.
- The owners ask the City of Fullerton about permits and inspections for the work.
The new island drain was designed with the plumber, the sagging section was replaced while the floor was open, and the permit question was settled with the city before work started.
Order of decisions
- Design stage
- Camera inspection of the existing drain.
- Before demolition
- Permit questions answered by the city; contractor license checked at cslb.ca.gov.
- Rough-in
- New drain and vent installed under the slab and in the island.
- Before cabinets
- Inspection as required by the city.
- Finish
- Sink, disposal and dishwasher connected and tested.
Questions raised and who answered
| Question | Who to ask |
|---|---|
| Is a permit needed for the new drain? | City of Fullerton |
| How will the island sink be vented? | Licensed plumber, subject to city rules |
| Should old pipe be replaced while the floor is open? | Plumber, based on the camera video |
| Dishwasher air gap or high loop? | Plumber; check with the city |
Takeaways
- Inspect the old drain before finalizing the layout.
- Treat venting an island sink as a design item, not an afterthought.
- Settle permits before demolition.
- Replace failing pipe while it is accessible.
Common questions
Is this a real remodel?
No. It is a hypothetical example.
Why camera the old drain before a remodel?
Problems under new cabinets and flooring are harder to reach later. Knowing the pipe condition early shapes the plan.
Do island sinks clog more?
Not necessarily, if the drain is sloped and vented properly. Poor slope or venting can cause slow draining.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.