Q: I live in a 1940s house with a kitchen that has never been updated. I’m tired of doing the dishes by hand and would really like to get a dishwasher. I don’t have a garbage disposal and don’t really want or need one. I compost all my organic food waste.
Is it possible to get a dishwasher or am I doomed to continue with washing dishes by hand. Do I have to spend big bucks to have the kitchen remodeled? I’m pretty handy so if possible I’d like to do this myself using the existing kitchen cabinets.
The counters are 25 inches deep with tile countertops, and the counter height is 35 inches. There are two side-by-side banks of drawers to one side of the sink measuring 26 inches between the stiles. This seems to be a perfect place for a dishwasher. What do you think?
A: Yes, you can have a dishwasher in your kitchen. Furthermore, you can do most of the work yourself and save a bunch of money. Four things are necessary for a built-in dishwasher: a place for it; a water supply line; a drain line; and power. We’ll take these in order.
Cabinet space: Standard under-counter dishwashers are 24 inches wide, 24 inches deep and approximately 35 inches high with adjustable legs. We’ve installed a dishwasher in an opening a little less than 34 inches tall. Based on your description, it sounds as if it’ll be a tight fit, but a fit nonetheless. There are narrower models and also single-drawer models with different dimensions available if the standard size won’t work. We’re sure that with a little research you can find one that will fit your space.
The drawer banks are an ideal location. It’s best to locate a dishwasher close to the sink for easy access to water and waste lines. Often 1940s vintage cabinets were built in place. Getting your opening should be as easy as removing the drawers, cutting out the cross rails and cutting out the bottom of the cabinet with a reciprocating saw.
Water supply: A dishwasher needs hot water. The closest source is the hot water supply under the sink. Replace the shutoff valve with a new one that connects both the sink and the dishwasher to the hot water line. The new valve, also known as an angle stop, will have a vertical outlet to be connected to the faucet and a horizontal outlet to supply hot water to the dishwasher. Use a long braided wire hose available at plumbing supply houses, hardware stores and home centers for the connection. You may need to drill a hole in the side of the cabinet to route the hose from the shutoff valve to the dishwasher opening.
Drain line: The dishwasher will come with a hose used to connect the dishwasher to the drain under the sink. Normally the hose is connected to an inlet in the garbage disposal. Because you don’t have one and don’t want one a little simple plumbing is in order. Water empties from the sink, through a strainer, into a tailpiece connected to a p-trap and then into the waste line. To connect the drain hose replace the straight tailpiece you have now with a tailpiece that looks like a "Y." Secure the drainage hose to the "Y" with a hose clamp.
Depending on the local plumbing code, you may have to install an air gap in the countertop. This will entail cutting a hole in the tile with a diamond-tipped hole saw attached to a drill. An air gap is a backflow preventer, keeping dirty water from re-entering the dishwasher. If an air gap is not required, the same thing can be accomplished by securing the drain line with a clamp at the top of the sink cabinet.
Here’s a YouTube video on drain lines and air gaps that we think is worth watching: http://www.youtube.com/watch?v=t7dEkdHjR84.
Power: Local codes usually require a dishwasher to be on a separate circuit that may be shared with a garbage disposal. The size of the wire and the circuit breaker will depend on the load the dishwasher draws. To be safe, we use 12-gauge wire run to a duplex plug and protected by a 20-amp circuit breaker. If the electrical box is surface-mounted, use armored cable to run the line. This is the only part of the job that may not be appropriate for your do-it-yourself project. It depends on your experience and your level of comfort working with electrical wiring.
With the water, drainage and electrical in place, read the dishwasher manual for hookup instructions. In any case, because there is some question as to whether an air gap is required and there is new wiring involved, get a permit and have the job inspected.