The average countertop has an unbroken finish, which means it covers the entire base cabinet, as well as any dishwasher that is installed. Any dishwasher that is put into place needs to fit into the slot made for it beneath the finish countertop, which goes across the top of the dishwasher and spans the gap from the base cabinets on each side of the dishwasher. Dishwashers are not designed with a finished hardtop usable as a countertop setting but are rather designed to fit tucked away within the cabinets. When selecting a dishwasher, keep your finish countertop height in mind to ensure you order the correct height.
Almost all dishwashers come with adjustable legs that allow you to manipulate the height of the dishwasher during and after installation. Always order a dishwasher that is shorter than what you actually need for the installation, then adjust the legs after the fact to bring it up until it matches the underside of the countertop. Or, as is the case with dishwashers that sit to one side of the countertop as opposed to in the middle, match the height of the overall countertop, even if it isn’t built in. The legs are also used to level the dishwasher for proper drainage.
In many remodel situations, you are faced with a countertop that you cannot remove because it would damage the entire base cabinet. That means replacing a dishwasher becomes a matter of working with what you have available. In the case of custom cabinets that are larger than traditional 36-inch cabinets, this means a space left behind that is larger than what most suburban dishwashers fill. Build a wooden platform to match the existing cabinetry to bring your dishwasher up to height, and use the adjustable legs for any needed tweaks.
Portable and Compact Units
While the average dishwasher is around 34 inches high, a variety of compact and portable units vary in size. Some units, such as drawer dishwashers, are built into the cabinets and have a pull-out drawer or door that looks just like a cabinet drawer. They range in height from 18 to 32 inches as a general rule. Portable units also vary in height, and other compact units are built so that you can hide them inside a cabinet cubby with a swinging door that shields the dishwasher from view. The adjustable legs still allow the dishwasher to be set on level, but otherwise their height is independent of the overall cabinets.