Dishwasher Air Gap Alternatives  


If you’re installing a dishwasher, you’ve probably been warned about the need for an air gap. Unfortunately, this piece of hardware is about as ugly as it is useful. Fortunately, you can pick a solid dishwasher air gap alternative like a check valve or a high loop. However, it is very important that you check with your local plumbing code to make sure that you are aloud using an alternative.

The Dishwasher Air Gap

Before you look at a dishwasher air gap substitute, you should know why the Air Gap is used. It’s the go-to solution for a fairly major problem and one that requires minimal effort to install. The major aesthetic flaw of the piece, though, does require some alternative solutions.

How it Works

The air gap works through the basic principle of separation. Because there is a literal gap between the clean and dirty water, there is no possibility of dirty water getting back into your clean water system. The air gap separates the line running the dirty water from the hose going to the drain.

Example: Picture your bathtub over flowing the water in the tub will spill out over the edges or into the upper drain before it reaches the faucet.

Air Gap Components

Part of the utility of an air gap is that it’s relatively simple. You’ve probably seen the exterior of the piece, which usually looks like some kind of metal cylinder. Underneath that cylinder is a bit of piping. There’s no moving parts here, which does help to ensure that these pieces keep working.

Air Gap Location

Generally speaking, your air gap is going to be placed about two inches above your sink. This placement helps to ensure that you won’t have to deal with any kind of backwash getting back into your water supply.

If you do not have enough holes you will have to drill a hole for the Air Gap. Also, if you have an under mounted sink you will need your counter top people to drill a hole in the granite/quartz/concrete counter. It can be located beside the sink as well.

The drain hose coming from the air gap can be connected either above the p-trap or directly into the garbage disposal.

Air Gap Costs

Air gaps are actually fairly inexpensive, they can cost you anywhere from $20.00-$60.00 USD. They don’t necessarily look great, but they are a good option for those who are looking to save money. You can generally find an Air Gap for under thirty dollars and some actually cost less than ten dollars. The quality of the product is, of course, generally reflected in the price that you pay.

Air Gap Alternative 1: The High Loop

Another fairly common alternative to the air gap is the high loop. This is a fairly simple alternative that doesn’t require any special parts and that tends to be looked upon fairly well by most code enforcement agencies, but it is also one that requires the user to properly place a disposal pipe. Still, it’s a fantastic choice for those who want to keep their hardware below the counters.

How the High Loop Works

The high loop basically utilizes gravity in order to keep wastewater from flowing into your clean water supply. This is accomplished by keeping the drain hose up above the water level. It’s actually a fairly elegant solution, utilizing nothing more than the basics of physics to help to keep your water supply in good shape without requiring you to invest in any major hardware.

High Loop Components

The only component that you’ll need for the high loop is something to keep the drain hose in place. This can be a set of brackets, a set of hooks, over even zip ties (which are, of course, not recommended). The key to this working is the type of material that you use, but rather the placement of the pipe.

High Loop Location

One of the big reasons that people turn to the high loop is that it can be placed underneath the sink. In fact, you can even keep it fairly close to your garbage disposal, which can help to solve a few other problems with your water system management. Generally speaking, though, you can put the High Loop anywhere under your sink that has the appropriate amount of room.

You do not want to place the high loop in front of your sink. The reason being because every time you open your cabinet the hose will be hanging in front of the door opening.

Note that the drain hose end that is not connected to your dishwasher should be hooked up either before your P-trap or directly into the garbage disposal.

High Loop Cost

The You will need to purchase the drainage hose which will range from $9.00 to $30.00 depending the length and quality of the hose. The clamps that you will need to can cost anywhere from $1.00 to $5.00 depending on how many you purchase.

Perhaps the best part about the high loop is that it is fairly inexpensive. You can pick up the relevant pieces for fairly cheap, especially if you aren’t afraid to do a little work on your own. If you’d like an easy-to-install kit, though, you should end up paying less than twenty dollars for everything related to installation.

Air Gap Alternative Two: Check Valve

The check valve is a very common in dishwashers. It’s a simple valve that allows the homeowner to avoid having any hardware above the counters, improving the look of his or her kitchen without sacrificing any utility. It’s not approved for use in every location, but it is a solid option for many.

Note that most new dishwasher will have a flap check valve which is located where the drain hose connects to the sump pump.

I personally would not recommend this part as an alternative but rather a second fail safe to use in tandem with the high loop method.

How it Works

A check valve, also known as a non-return valve, works by ensuring that fluids only flow in one direction. When fluid flows forward into the valve, it opens up. When the fluid stops flowing, though, the valve closes shut. This keeps water from moving back into your water lines, helping to keep it clean and avoiding any kind of backwash.

Check Valve Components

The check valve is a single piece. It fits onto your existing piping, using its internal mechanisms to control the direction in which water and/or waste is flowing. The internal composition of the device does have a moving part, but it’s all contained within the same device.

Depending on the check valve that you purchase it can be either spring loaded or use a flap. If it is spring loaded you will have to make sure that the dishwasher can create enough pressure to open the valve.

Check Valve Location

If you have a check valve on your dishwasher, you’ll usually find it in one of two locations. Some are placed near the chopper blades, while others are located in the upper sump assembly. Both locations allow for the easy flow of waste-water into the check valve, though both locations can be problematic if the check valve becomes damaged.

Check Valve Cost

Check valves definitely run the gamut in terms of pricing. If you’re looking at a cheaper plastic model, you should expect to pay anywhere from $5.00 to $20.00. Metal models have an even greater range, though – the cheaper metal valves tend to run around ten dollars, while high-end valves can easily cost more than one hundred dollars. Generally speaking, more complex valves made out of heavier material are going to cost more than lighter, theoretically less durable valves.

Recent Content