What is the difference between Topmount and Undermount? Regular and Farmhouse/Apron?
There are a lot of sink options out there and it can be confusing trying to choose between them in the stress and frenzy of a remodel. To help a little with that stress, here’s a little info on the three main sink types you can choose from:
Topmount – Topmount, Overmount, or Drop-in sinks are installed from the top of the counter and come with faucet holes pre-built into the sink. A hole is cut into the surface of the counter which is big enough to encompass both the basin and the space for the faucets and accessories (such as soap dispensers) to fit within it, and then the sink is placed into that hole. The lip or flange on the sink is much wider than on an undermount or dual-mount sink, and this is what the sink rests on to hold it in place. Caulking is piped around the outside of the sink hole, and then the sink is installed into the space created. Once the sink is placed correctly it is caulked around the outside edge of the flange to lock it in place and also to prevent water infiltration. Sometimes installers will use the sink maker’s sink clips to set the sink more firmly into the counter area, but depending on your counter type they may not be able to do so. Topmount sinks are are versatile, affordable, and best for spaces in which the sink must be regularly replaced or with Formica countertops. Because these sinks don’t have a visible countertop edge the labor tends to cost a lot less than the labor for an undermount sink. The caulking around the edges of the sink should be replaced periodically to avoid tarnishing and molding – especially in damp climates.
Undermount – These sinks are installed from below the countertop and have a visible rim in the sink hole cutout where the inside edge of the counter meets the sink. This area must be polished and shaped to the sink according to the sink manufacturer’s template. The faucet holes in an undermount sink are drilled into the stone behind the countertop or into the wall behind the sink for wall-mounted faucets. If the homeowner selects 2CM countertop material and a stainless steel sink then the sink flange will be sandwiched between the plywood and the countertop and held in place with industrial strength epoxy, sink clips, or both. If the sink is made of a heavier/thicker material than stainless steel then a support structure must be constructed within the cabinet box to keep it in place – usually out of 2×4 planks. There are dual-mount sinks which have a flat flange but also have faucet holes built-in, but because QGC installers cut by hand these sinks must be installed as topmount sinks. Undermount sinks are a popular choice in more modern settings due to the clean look and ease of upkeep, but are much harder to replace when a sink is damaged. The extra labor of grinding, polishing, and shaping the sink hole cutout means that these sinks are more expensive overall to install.
Farmhouse/Apron – Farmhouse (also known as Apron Front) sinks are predominately installed as undermount sinks with a visible edge, but unlike most undermount sinks they extend out past the front of the counter with a broad “apron” fronting. These sinks require special cabinets with shorter doors in order to accommodate the deep sink front sitting past the cabinet face. These are popular sinks due to their deep basin, heavy-duty material, and comfortable use ; the fact that the front edge of the countertop is removed completely means that homeowners can stand right up next to the sink face rather than leaning over the counter edge which spells good things for your back during a prolonged dishwashing session. Farmhouse sinks come in a variety of materials, but keep in mind that the heavier your sink material is the more structural support you will need within the cabinet. Make sure that during installation the sink overhangs the cabinet doors slightly or your installer uses a drip rail over the doors to avoid water dripping on your cabinets and causing damage. Many porcelain, cast-iron, or fireclay sinks will come with rounded front side corners which will not match the sharp corners of the cabinet box visually.