When you finish a meal at home, you're often left with a variety of food scraps -- bones, vegetable peels, pizza crusts -- that need to be disposed of somehow. You can compost them (requiring a trek out to the compost pile), throw them in the trash (where they can smell bad and attract pests) ... or, if you have a garbage disposal, just push them into the sink drain to be ground up and washed away.
If you're hooked up to a local sewer system, the food waste gets flushed into the pipes to be treated at a wastewater plant. In many cases, this is better for the environment than sending the waste to a landfill or an incinerator. Processing finely ground waste through the water treatment system is a more efficient way of dealing with it than sending it to a landfill, where it can take months to break down, producing planet-warming methane in the process. In fact, some municipalities actually require garbage disposals (or waste disposers, as they are also known) to be included in all new homes.
However, in other areas, the sewage system isn't equipped to handle the extra waste load garbage disposals can produce. Some towns also discourage their use because they're afraid homeowners will misuse them by dumping fats and other greasy residues, which can clog sewers. In areas like this, home composting is a better option for dealing with food waste.
Garbage disposals can also pose a problem for homeowners who use septic systems. Unless the system is properly sized and designed to handle the extra waste and water, food waste can clog up the system - especially if it isn't finely ground enough. This means homeowners may need to pump out the tank more often, and it could shorten the overall life of the system. However, some garbage disposals are specially designed for use with septic tanks. Typically, they use enzymes or bacteria to help break down the waste so it won't overburden the system.
If you decide that a garbage disposal is right for you, the next step is to choose the best model for your household. In general, the more often you use your disposal, and the more waste you put down it at a time, the larger the unit you need. So, for instance, if your household has more than four members and you cook at home more than a few times per week, you'll need a disposal with a large chamber capacity and a powerful motor - at least 0.75 horsepower. By contrast, if you're a one- or two-person household and need to dispose of food waste only a couple of times a week, you can probably manage with a smaller 0.5-horsepower model. However, if you routinely host large dinner parties, you may want to invest in a more powerful disposal to make sure it can keep up with your biggest jobs.
Also consider the area you have available for your garbage disposal. Disposals are installed under the kitchen sink and hook up directly to the drain. If you have a dishwasher, its water outlet is hooked up to the disposal's. Larger, more powerful disposals will typically take up more space than some less robust models. Less powerful disposals also tend to create less noise and vibration, an important benefit for homeowners with sinks made out of lighter-weight materials like thin-gauge stainless steel.
Garbage disposals come in two basic types: continuous feed and batch feed. To use a continuous-feed garbage disposal, you simply turn on your water faucet, switch the unit on, and begin pushing food waste down the drain into the grinding chamber. Using this kind of disposer is quick, easy and intuitive, but isn't necessarily safe. Non-waste items can drop into the unit, requiring you to fish them out with a hand or tool, and you have to be extra careful not to turn on the disposal while you're doing it. This can make continuous-feed disposals risky in homes with small children—or easily distracted adults.
Batch-feed disposals eliminate this danger. To use this type of disposal, you push the waste into the drain, then cover the hole is with a magnetic lid that activates the disposal's power switch. Lifting the lid to add more food scraps turns the disposal off. This is slower than using a continuous feed model, but that's not always a bad thing, since it minimizes the strain on older pipes. Slowing down the process also reduces the risk of dropping silverware in to be mangled by the disposer's blades.
When you have a high-performing garbage disposal, you can entertain large groups without fearing the cleanup that comes after. The best models work fast, run so quietly that you can still carry on a conversation, and grind food waste finely so there's minimal chance of blocking your drain or jamming the machine. They're also made of high-quality materials, including stainless steel grinding chambers, so they won't corrode or rust quickly. Paying for the best performance usually gets you the longest, most comprehensive warranty as well.
No other garbage disposal on the market earns so many recommendations from both professionals and homeowners as the InSinkErator Evolution Excel (Est. $320), a continuous-feed garbage disposal. In professional tests, its 1-horsepower motor reduces food scraps to tiny particles. Owners on retail sites consistently agree that the Excel can chop up anything they throw at it, including steak bones, corncobs, watermelon rinds, a pineapple top, and an avocado complete with the skin and pit. What impresses them still more, however, is its quietness. Many users report that this disposal makes so little noise, they have to check the switch to make sure it's running.
Most homeowners say they had no trouble installing the InSinkErator Evolution Excel, but some caution that it's very heavy and takes up a lot of space under the sink. On the plus side, that extra weight reflects its sturdy construction. We saw almost no durability complaints about this disposal, which has a rust-resistant stainless steel grinding chamber and is backed by a 7-year warranty. The main problem users have with the Excel is that its baffle -- the rubber gasket that covers the drain --creates too much of an obstruction. Drainage is slow, and some users say they have to shove food down into the disposal opening by hand.
Although the InSinkErator Excel is certainly tough, professional tests show it's not particularly fast. If speed is a priority for you, consider the Waste King Legend 8000 (Est. $140), which earns good marks for both speed and fineness of grinding. Users agree that this 1-horsepower continuous-feed disposer is powerful enough to handle all types of waste, and most find its "EZ Mount" system very easy to install. However, they're much more divided over its noise level, with some praising its quietness and others complaining that it's too loud. Professional tests show the Waste King's noise level to be moderate—not as loud as some cheaper disposals, but certainly not as whisper-quiet as the InSinkErator.
Unlike the InSinkErator, the Waste King does not have a stainless-steel grinding chamber. The actual grinding components are made of stainless steel, but the chamber is nylon lined with fiberglass. This means it can't rust, but cracking is a possibility. Although the Waste King is backed by an impressive lifetime warranty, users are split about how well the company honors it. Of the few users who have had problems, about half praise the company's outstanding customer service, while the other half complain that reps are hard to reach and seize on any possible excuse to refuse to cover repairs.
Another continuous-feed disposer that gets good marks across the board is the 0.75-horsepower KitchenAid KCDS075T (Est. $250). Though it's not as fast as the Waste King in professional tests, it matches the InSinkErator's quietness and fine grind size but costs less. This garbage disposal doesn't receive nearly as much user feedback as the Waste King or the InSinkErator, but what we found is highly positive. Owners describe it as durable, easy to install, and easy to keep clean. However, its 5-year warranty isn't as impressive as the InSinkErator's 7 years, or the Waste King's lifetime warranty.
Batch-feed garbage disposals have the same basic inner workings as continuous-feed units; the only difference is how they switch on. Most continuous-feed disposers begin grinding when you flip a switch on the wall or countertop and keep running regardless of what you stuff inside. Batch-feed disposals, on the other hand, activate only once the drain has been covered.
To start a batch feed disposal, you must line up magnets on the unit's cover and the mouth of the disposal. Since you can't run the disposal and push scraps down the drain at the same time, food waste must be ground up in batches. These disposers take more time to do the job than continuous feed models and aren't ideal for large families, but parents of young children have the peace of mind of knowing the disposal won't operate while fingers are in the drain. In addition, turning a batch feed disposal on with its cover means not having to touch any electrical switches.
On the downside, there are few batch feed garbage disposals available, and fewer still with very much positive feedback. We found only one with positive ratings from both professionals and homeowners: the 1-horsepower Waste King Legend 8000TC (Est. $180). Like the continuous-feed Waste King Legend 8000, the 8000TC gets top marks in professional tests for its speed and the fineness of its grind, although it doesn't do quite as good a job processing vegetable scraps as the 8000. Users at Amazon.com agree that it's powerful and runs smoothly without clogs. They also describe it as easy to install.
Most users consider the 8000TC's batch-feed mechanism a major plus, since they no longer have to worry about either fingers or utensils finding their way into a running disposal. However, some users note that the batch-feed system is somewhat tricky to use: the disposal won't start unless the cover is positioned exactly right, and while it's in place, no water can get in to help flush away the processed waste. Also, like the Legend 8000, the 8000TC is a bit loud for some users. There are few comments about durability, either positive or negative, but users are impressed by the unit's 10-year warranty.
The only other batch-feed disposal that receives any feedback in our sources is the InSinkErator Evolution Cover Control Plus (Est. $260). In professional tests, it doesn't grind waste quite as finely as the Waste King, but it is quieter—a feature that homeowners particularly appreciate. Owners also describe this disposer as powerful, sturdy, and easy to install. On the downside, it's heavy and bulky -- too bulky to fit under some sinks. It's backed by a 7-year warranty.
Although the best-rated garbage disposals cost at least $180, there are some decent continuous-feed models on the market for considerably less than that price. When you buy a cheaper garbage disposal, you generally sacrifice two things: horsepower and build quality. While the disposers covered elsewhere in this report have 0.75- to 1-horsepower motors, budget garbage disposals generally have no more than 0.5 horsepower. However, this is sufficient for a medium-sized household that grinds scraps daily or a few times per week. Cheap garbage disposals also tend to have parts made of galvanized steel or plastic rather than stainless steel. This often—but not invariably—means they don't hold up as well over time.
In the under-$100 price range, the best-rated garbage disposal is the KitchenAid KCDB250G (Est. $100), which receives overwhelmingly positive reviews from hundreds of owners at the retail sites across the Internet. While some of these sites include reviews originally posted at KitchenAid's site, the feedback is nonetheless impressive -- for example a 4.6-star rating at retailer ABT.com following more than 400 reviews. At Amazon.com, feedback from that site's customers (only, as Amazon.com does not pull reviews from other sites), grant this budget KitchenAid garbage disposal an indenical 4.6-star rating based on more than 150 reviews.
This 0.5-horsepower garbage disposal isn't as powerful as higher-priced models, but most owners say it has more than enough power for their needs. Owners also praise the ease of installation and cleaning.
The most common complaint we saw about the KCDB250G is that it's too loud. About 10 percent of reviews that can be seen at ABT.com, list "noisy" as a drawback of this disposal. However, those reviews are far outnumbered by reviews from users that list "quiet" as an advantage, so it seems to be a matter of differing standards. The other weak point is the warranty, which is the shortest we've seen at only 1 year. However, durability doesn't seem to be a major problem for this disposal as we found only a handful of complaints about leaks or other failures.
Although the KitchenAid gets good reviews from owners, it hasn't been covered in any professional sources. The only budget-priced disposal that has is the InSinkErator Badger 5 (Est. $90), which receives good scores for its speed and grind size. On noise, however, it doesn't fare so well; in fact, it's louder than nearly every other machine in the test.
The Badger 5 has received thousands of reviews from owners at retail sites like Amazon.com, Lowes.com, and Walmart.com. Owners find it very easy to install, and most of them say its noise level is not a problem. The real weak point for this disposer is durability. We saw dozens of reviews complaining that the Badger 5 developed leaks within a few years after purchase, usually as a result of rust or cracks in the case. Fortunately, the disposal is backed by a 2-year warranty that covers in-home servicing and parts, so you can expect it to hold up at least that long.
We found similar comments for the InSinkErator Badger 1 (Est. $85), which is essentially a smaller version of the Badger 5. It's less powerful than the Badger 5 --only 0.33 horsepower -- but it's also more compact, at less than 12 inches high and just over 6 inches wide, allowing it to fit into small under-sink spaces. Like the Badger 5, it gets high marks from owners for ease of installation and ease of use, but there are many complaints about noise and durability.
Another good option for tight spaces is the 0.5-horsepower General Electric GFC520V (Est. $75). At 12.7 inches tall and less than 5.5 inches across, it's the narrowest garbage disposal we've seen. Owners say it's easy to install, quiet, and surprisingly powerful. Its biggest drawback is its small capacity, which limits the amount of waste it can process at a time. Like the KitchenAid KCDB250G, it comes with a 1-year warranty.
Homeowners with septic systems rather than sewers must always be careful about what they put down the drain. Food waste from a garbage disposal can clog up the system, especially if it isn't ground finely enough. Even finely ground waste can fill up the tank more quickly, requiring it to be pumped more often—an expensive and time-consuming process. Because of this, homeowners with septic systems are often told they shouldn't use a garbage disposal at all.
A possible work-around is the InSinkErator Evolution Septic Assist (Est. $200). This continuous-feed disposer contains a "Bio-Charge" cartridge that automatically injects enzyme-producing microorganisms into the unit, helping to break down waste as it flows into the septic system. User reviews at sites like Amazon.com and Build.com say this system works as advertised, and they've had no problems with plumbing clogs or backups since installing it. They also appreciate the fact that the Bio-Charge dispenser works automatically, so they don't have to add any chemicals by hand. According to the manufacturer, one bottle of Bio Charge has enough for 295 uses and should last about four months with normal household use.
Aside from its unique Bio-Charge feature, the Evolution Septic Assist is a solid disposal boasting a 0.75-horsepower motor and stainless steel construction. Although it's large and takes up a lot of real estate under the sink, users generally say it's easy to install and runs very quietly. Their main complaint is that installing it slows down the drainage in the sink. Some users find that they have to push food waste down into the disposal by hand, as the motor won't suck it down on its own. The InSinkErator Evolution Septic Assist is backed by a four-year warranty that covers both parts and in-home service.
The Evolution Septic Assist is the only garbage disposal we've found that's designed specifically to work with a septic system. Some reviewers say they've successfully used other garbage disposals while on septic tanks, such as the Best-Reviewed InSinkErator Evolution Excel, but the Bio Charge catalyst makes the Septic Assist the safest bet for any owner who wants to be sure the garbage disposal and the septic tank play nicely together.
The only credible professional test of garbage disposals we found was at ConsumerReports.org. Editors there put beef bones and vegetable scraps through 13 disposals and compared their speed, fineness of grinding, and noise level. We also picked through thousands of user-written reviews on retail sites such as Amazon.com, HomeDepot.com, Lowes.com, Walmart.com, and ABT.com. These sites offer information on long-term durability and ease of installation, as well as coverage of disposals that weren't included in the ConsumerReports.org test.