Installing a disposal where one already hangs usually takes a plumber a couple of hours, and Fixr puts a typical installation at $300 to $600 nationally, unit included, with the unit alone at $50 to $400 depending on type. A first-time install, where the kitchen has no outlet, switch or drain connection, costs more. Related sink work is grouped on the disposal repair and sink fixtures page; this page sticks to the install.
What happens during a disposal installation, step by step?
Under the sink, the installer empties the cabinet, takes out the old unit or the strainer, seats the flange, tightens the mounting ring, hangs the new disposal, joins its discharge to the trap, links the dishwasher hose if there is one, supplies power and finally checks for drips and rattles. A like-for-like swap tends to fill an afternoon or less.
In order:
- Prep. Power off, water off, cabinet emptied.
- Out with the old. Disconnect discharge and dishwasher hose, release the mounting ring.
- Mount. Seat the sink flange with plumber's putty, tighten the mounting assembly.
- Dishwasher knockout. If a dishwasher connects, the plug inside the inlet is knocked out; leaving it in blocks the dishwasher drain.
- Hang and connect. Attach the unit, align the discharge with the trap, tighten the fittings.
- Power. Plug into the outlet or connect to hardwiring per the instructions.
- Test. Run water, check for drips, listen for rattles.
How much will the installation set me back?
Fixr gives a national average of $500 for the whole job, typically $300 to $600. The unit runs $50 to $300 in continuous-feed form and $100 to $400 as batch-feed, and plumbers bill $75 to $200 an hour. A new circuit or drain plumbing lifts the total.
These are national numbers, not Mission Viejo quotes. Ask for the unit, labor and any electrical or drain work as separate lines.
| Item | Fixr national figure |
|---|---|
| Whole installation, unit included | $300 to $600 typical |
| Continuous-feed unit | $50 to $300 |
| Batch-feed unit | $100 to $400 |
| Electrician to install a new outlet or circuit | $120 to $360 |
| New drain or trap work | Extra, by the plumber |
Related pricing for other sink fixtures is in the faucet installation cost and faucet replacement cost pages.
What should you decide before the installer arrives?
Settle three things: the type, the power and the connections. Continuous-feed units run while the switch is on, while batch-feed units run only with the lid in place. Pick a horsepower to suit the household, then confirm whether the sink has a switch and an outlet and whether a dishwasher hooks in.
Questions worth settling:
- Horsepower. Larger motors grind more easily and cost more; a small household may do fine with a modest one.
- Feed type. Continuous is most common; batch feed has a safety lid.
- Materials. One price guide notes that stainless parts hold up better than aluminum, which corrodes and leaks sooner.
- Noise. Insulated models are quieter, at a higher price.
- Fit. Measure under-sink space; some units need height and clearance for the trap.
- Warranty. Read what the manufacturer's terms cover and what voids them.
Does a disposal need electrical work or a permit?
Power has to reach the sink. With an outlet in the cabinet and a wall switch, the plumber simply plugs in. Without them, adding a switch or circuit is electrical work for an electrician and may involve the city. A straight swap often needs no permit; the city's Building Services Division can confirm when you are unsure.
State contractor licensing begins at $1,000 and covers work needing a permit. Electrical work has its own classification, so wiring may go to an electrician arranged alongside the plumber. Do not run a cord through a cabinet wall or splice wires yourself without the proper junction box. Hard-wired units must be wired with the circuit off and connections inside the supplied box.
Can you install a garbage disposal yourself?
Someone handy can swap a unit that uses the same mounting style and a plug-in cord. The hazards are leaks, a knockout plug left in place so the dishwasher cannot drain, and wiring mistakes. Hand new wiring, a changed drain layout or any doubtful step to a plumber and an electrician.
If you try it, switch off power at the breaker, not just the wall switch, take photos of the old connections, and test for leaks with a paper towel under each joint after running water. Never reach into a disposal; use a wrench in the bottom hex socket or the tool provided to free a jam, with power off. Cutting a corner here is how fingers get hurt.
Which points belong in the installation quote?
Learn what the quoted price covers, line by line: the unit, labor, hauling away the old disposal, electrical work and the dishwasher hookup. Add brand, horsepower, warranty terms and the person doing the wiring. A license number and written figure should come first.
A home improvement deposit cannot legally exceed a tenth of the price, or a thousand dollars if that is less. A visit starts with the quote form, and the Capistrano Plumbing home page lists other jobs. Afterwards, unclogging a kitchen sink and why a sink drains slowly.
Common questions
How much of the day does it take?
A like-for-like replacement is a short visit, often a couple of hours. A first install needing a new outlet, switch or drain change runs longer and can involve two trades. Request a time estimate, including whether the electrician arrives with the plumber or separately.
What should I confirm before booking an install?
Does the price include the unit and taking the old one away? Which horsepower is proposed, who does the wiring and what does the warranty cover? Get a license number you can verify, a written quote, and confirm the dishwasher connection is in scope if you have one.
Should someone be in the kitchen?
Yes, an adult who can open up and agree to a change if a surprise appears below the basin, such as a rotted cabinet floor. Empty the cabinet beforehand, since cleaners and sponges otherwise end up on the floor, and keep pets out of the room.
Is a garbage disposal good for the plumbing?
Disposals handle soft scraps, but grease, fibrous peels, bones and large amounts of starchy food can clog drains. Run cold water while it works and for a short time afterward. If your drains are old or slow, a disposal can make things worse, so a plumber can check the line.
Will a disposal fit my sink?
A standard kitchen sink will usually take a disposal, but cabinet space and trap alignment matter. Double sinks and drop-in or undermount sinks are installed differently, and the plumber may need a different flange. Measure under-sink clearance and tell the installer the sink type up front.
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