Garbage Disposal Installation in Denver, CO
New disposals, replacements, and dishwasher hookups installed right the first time. Flat-rate written quote before we touch anything, no money down. Licensed, bonded, and insured.
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Garbage disposal installation and replacement across Denver
Deft Plumbing installs and replaces garbage disposals across Denver, CO, including dishwasher hookups, first-time units, and swaps for one that's quit. We confirm the right horsepower for your household, quote a written flat rate covering the disposal, mounting hardware, drain connection, and haul-away, then leave you with a leak-tested, code-compliant setup. Licensed, bonded, and insured in Colorado. You know the total before we pick up a wrench, and there's no money down.
If your unit already runs but jams, hums, or leaks, that's a repair, not an install, and we cover that on our Denver garbage disposal repair page. This page is about putting in a new one. Here's what a generic listing won't tell you about a disposal install in this town: the two things that turn a fresh install into a first-week callback have nothing to do with the disposal itself. They're the dishwasher knockout plug and what goes under the sink flange, and we'll walk through both below.
Common garbage disposal installation issues we fix in Denver
New dishwasher hookup where the knockout plug was never removed
This is the single most common failed install we're called out to fix in Denver. A new disposal ships with a solid dishwasher inlet knockout plug in the drain port. If a dishwasher drain line is connected without punching that plug out first, the dishwasher can't drain into the disposal and water backs up into the machine. We remove the knockout plug on every dishwasher hookup and confirm flow before we leave.
First-ever disposal in a sink that never had one
Adding a disposal where none existed means a new drain flange, a new tailpiece configuration, and often a new dedicated electrical circuit. Code wants a 120V/15-amp circuit for a residential disposal, and older Denver kitchens sometimes share that outlet with the dishwasher and a few counter plugs. We check the circuit before we quote so you're not tripping a breaker every time both run.
Replacing an old or undersized unit
If your current disposal is past 10 years or a builder-grade 1/3 HP that stalls on anything fibrous, a replacement is the honest call. We size the new unit to how you actually cook, 1/2 HP for light everyday use up to 1 HP for a busy kitchen, and reuse or upgrade the mounting assembly so the new unit seats cleanly on the existing sink.
A flange sealed with silicone instead of plumber's putty
We see this on DIY and cut-rate installs constantly. Silicone under the sink flange looks fine on day one, then shrinks and lets water weep around the drain within the first year. The flange gets bedded in plumber's putty, full stop. It stays pliable, seals under compression, and comes apart cleanly the next time the unit is serviced.
Dishwasher drain looped wrong so the disposal back-siphons
A dishwasher drain that drops straight down into the disposal lets dirty sink water siphon back into the machine. Colorado plumbing code requires either a counter-mounted air gap or a properly installed high-loop. We route the drain hose up to the underside of the countertop and secure it there so the loop does its job, which keeps the fix invisible instead of drilling a hole in your counter for an air gap.
Chronic jams and stalls from an underpowered unit
If you're constantly resetting a disposal that stalls on celery, potato peels, or coffee grounds, the motor is too small for your kitchen, not broken. We match horsepower to your usage at install so the new unit clears what the old one choked on, rather than selling you the same undersized motor again.
What to expect, start to finish
1. Phone triage
Call (720) 880-8064 during business hours. We ask whether it's a first install or a replacement, whether a dishwasher is tied in, the sink and cabinet setup, and how the kitchen gets used. For most Denver homes we can recommend a horsepower and quote an install range over the phone.
2. On-site assessment
We check the existing drain and trap, the mounting assembly under the sink, whether a dishwasher drain connects, and the electrical, confirming there's a 120V/15-amp supply and whether it's shared. We flag anything that affects the install, like a missing dedicated circuit, before we quote.
3. Written flat-rate quote
You get a written quote covering the disposal, the horsepower we recommend and why, the mounting hardware, the drain and dishwasher connection, and haul-away of the old unit. No money down. No work starts until you sign off, and nothing changes without your written approval.
4. Mount and seal the flange
We bed the sink flange in plumber's putty, never silicone, seat the mounting assembly, and hang the disposal on it. Putty stays flexible and seals under the compression of the mounting ring, which is what keeps the drain from weeping in year one.
5. Drain, dishwasher, and electrical connections
We knock out the dishwasher inlet plug when a dishwasher ties in, connect the drain to the trap, route the dishwasher hose in a secured high-loop per Colorado code, and wire or plug the unit into the 120V/15-amp supply. Every connection gets checked, not assumed.
6. Leak test and walkthrough
We run the unit under load, fill and drain the sink to check the flange and trap, run the dishwasher a cycle when it's connected to confirm it drains through the disposal, and walk you through the reset button and what not to put down it. You leave with a written warranty.
Why a Denver Disposal Install Comes Down to Three Small Details
Most garbage-disposal pages online treat the install as drop-in-and-done. After doing these across the Denver metro, our conclusion is that the disposal is the easy part, and three small details decide whether you call us back in a week. The first is the dishwasher knockout plug. Every new disposal ships with a solid plug blocking the dishwasher inlet port, and it has to be punched out before a dishwasher drain is connected. Skip it, and the dishwasher has nowhere to drain, so water backs up into the machine and the homeowner assumes the new dishwasher is defective. It's the number-one failed install we get called to fix, and it takes thirty seconds to do right.
The second detail is what goes under the flange. The sink flange gets bedded in plumber's putty, not silicone. Silicone looks clean on install day, then shrinks as it cures and lets water weep around the drain within the first year, which is exactly the callback we see on DIY and cut-rate jobs. Putty stays pliable, seals under the compression of the mounting ring, and comes apart cleanly the next time anyone services the unit. We don't cut that corner.
Colorado code note
A dishwasher drain can't drop straight into the disposal, or dirty sink water siphons back into the machine. Code requires an air gap or a properly installed high-loop, and Denver accepts a high-loop in lieu of a counter-mounted air gap. We route the hose up to the underside of the counter and secure it there, so you get a compliant drain without drilling a hole in your countertop.
The third is horsepower and the circuit behind it. A builder-grade 1/3 HP unit stalls on anything fibrous, so we size to how you actually cook, 1/2 HP for light everyday use up to 1 HP for a busy kitchen. A residential disposal wants a 120V/15-amp circuit, and older Denver kitchens sometimes run the disposal, the dishwasher, and a few counter outlets off the same one, which trips the breaker when two of them pull at once. We confirm the circuit before we quote so the new unit runs on a supply that can carry it.
When you don't need a new disposal
Here's the part a lot of companies won't put in writing: if your current unit hums, jams, or has power trouble, you probably don't need a replacement. A humming disposal is usually a jammed impeller freed in fifteen minutes, and a silent one is often just a tripped reset button or GFCI. That's a repair, and it's cheaper than a swap. Before you buy a new unit, read our Denver garbage disposal repair page or call and we'll tell you honestly which one you're looking at. We replace a disposal when it's past 10 years, leaking from the body, or genuinely underpowered for your kitchen, not because it stalled once on a chicken bone. For the full scope of what we cover on disposals and dishwasher hookups, start with our garbage disposal and dishwasher services page.
Deft Plumbing vs typical Denver plumber
| What you get | Deft | Typical |
|---|---|---|
| Dishwasher knockout plug | Removed on every dishwasher hookup, flow confirmed before we leave | Missed, then the new dishwasher backs up in week one |
| Flange seal | Bedded in plumber's putty, per manufacturer spec | Siliconed, then weeps around the drain within a year |
| Dishwasher drain routing | Secured high-loop per Colorado code, no counter drilling | Dropped straight into the disposal, back-siphons |
| Horsepower + circuit | Sized to your kitchen (1/2 to 1 HP), 120V/15-amp confirmed | Same undersized unit, shared circuit that trips |
| Quote method | Written flat-rate, signed before work starts, $0 down | Hourly + parts, total unknown until the invoice |
What Denver homeowners say
"Put in a new disposal and hooked up our new dishwasher at the same time. The previous plumber had left the knockout plug in and our dishwasher kept flooding. Deft fixed it in one visit, quote matched the invoice, no money down."
Verified Google review, Denver, CO
"Replaced a stalling builder unit with a 3/4 HP one and walked me through why the old outlet kept tripping. Straight answers, flat-rate, and it's been leak-free for a year."
Verified Google review, Denver metro
Denver garbage disposal installation questions
What size garbage disposal do I need?
Match the horsepower to how you cook. A 1/2 HP unit handles light everyday use for a small household. A 3/4 HP unit is the sweet spot for most Denver kitchens and clears fibrous scraps and small bones without stalling. A 1 HP unit suits a busy kitchen that runs the disposal hard and often. The 1/3 HP builder-grade units are the ones people replace because they stall on celery and potato peels. We size to your usage, not to whatever was there, and we tell you why on the quote.
Do I need to remove the dishwasher knockout plug on a new disposal?
Yes, and it's the most common install mistake we get called to fix. Every new disposal ships with a solid knockout plug blocking the dishwasher inlet port. If you connect a dishwasher drain without punching that plug out first, the dishwasher has nowhere to drain and water backs up into the machine. It takes thirty seconds with a screwdriver and a hammer to knock it out, but it has to be done before the hose is connected, and the loose plug has to be fished out of the disposal so it doesn't jam the impeller. We remove it and confirm the dishwasher drains on every hookup.
High-loop or air gap for a dishwasher drain in Colorado?
A dishwasher drain can't drop straight into the disposal, or dirty sink water siphons back into the machine. Colorado plumbing code requires either a counter-mounted air gap or a properly installed high-loop, and Denver accepts a high-loop in lieu of the air gap. The high-loop routes the drain hose up to the underside of the countertop and secures it there, which breaks the siphon without drilling a hole in your counter for an air gap fitting. We install the high-loop and secure it so it can't sag over time, which is the failure that lets back-siphoning start again.
Do you use plumber's putty or silicone on the flange?
Plumber's putty, always. Silicone under the sink flange looks fine on install day, but it shrinks as it cures and lets water weep around the drain within the first year. That's a year-one failure we get called to fix on DIY and cut-rate installs. Putty stays pliable, seals under the compression of the mounting ring, and comes apart cleanly the next time the unit is serviced. We bed every flange in putty.
Do I need a permit or a special circuit to install a garbage disposal in Denver?
A like-for-like replacement of an existing disposal doesn't require a permit. Adding a disposal to a sink that never had one may require electrical permitting if a new circuit has to be run. A residential disposal wants a 120V/15-amp circuit, and older Denver kitchens sometimes share that with the dishwasher and counter outlets, which trips the breaker when two things pull at once. We check the circuit before we quote and handle any permit as part of the flat-rate.
Should I repair my old disposal or replace it?
If the unit hums, jams, or has power trouble, that's usually a repair, and a cheap one, so start there before you buy a new unit. A hum is normally a jammed impeller, and a dead unit is often a tripped reset button or GFCI. Replacement is the honest call when the disposal is past 10 years, leaking from the body housing, or genuinely underpowered for your kitchen. We cover the repair side on our Denver garbage disposal repair page and will tell you on the phone which one you're actually looking at.