How to Install a Farmhouse Sink
Back in the day, a large farm sink was necessary to accommodate the many large pots and pans used regularly in the kitchen. In recent years, farmhouse sinks, also known as apron sinks, have seen renewed popularity.
These large drop-in sinks cover large portions of the counter, either wrapping around the front edge of the base cabinet or nestling in a recess within the cabinetry. Since they form an integral part of a cabinet’s front, they usually require special retrofits to fit.
Installing a farmhouse sink, therefore, takes serious work, but the final result offers an appealing alternative to regular kitchen sinks, becoming a robust cleaning spot, and sometimes even the design focal point of a kitchen.
They're particularly popular in kitchens with a rustic or country theme, especially if you're considering adding brass or copper elements, which often come embossed with decorative designs.
Pros and Cons of Farmhouse Sinks
The large capacity of apron sinks allows you to wash large and awkwardly shaped items like large pots, trays, and cookie sheets with ease.
These sinks can be versatile, too. They're available in fireclay, porcelain enamel, copper, brass, and natural stones like granite and soapstone, or stainless steel and other materials as well, that can accommodate different styles of decor.
If you're decorating in a rustic style, the fact that farmhouse sinks have been around for over a century means you might be able to acquire one at a garage sale, salvage yard, or estate sale for a reasonable price.
Apron sinks come at a higher cost than other options, and the requirement of cabinet framing modifications increases this price.
They also suffer an increased chance of leaks and spills, and their depth can encourage you to overload them, which can lead to breaking or chipping dishware and glasses.
Finally, they're bigger, so they're just more work to clean. This can be especially tricky with light-colored materials, some of which have to be washed with non-abrasive methods.
Step 1 - Choosing the Right Sink for a Better Outcome
There are different ways sinks are made to be installed.
1. Top Mounted
The top-mounted sink is one with a wide flange all around its perimeter at the top, which is larger than the countertop's cutout opening so that it can sit and rest directly on top of the countertop hiding all joints from the opening cutout.
This goes for all top-mounted sinks, including the farm sinks on which the flange wraps around the front edge of the casework, protruding from the apron drop on all three sides to partially cover the front of the cabinet.
2. Under Mounted
The under-mounted sink is a more recent and trendy innovation of sink installation where the sink is installed on a specially designed cabinet before the countertop is installed, completely covering three sides of the sink, revealing only the basin inside.
With three exposed edges of the countertop's cutout, it should not be made of absorbent material but rather of some type of stone.
3. Flush Mounted
The third one is not as common yet—the flush-mounted sink where the countertop is cut with precision (preferably by a countertop expert) to match the exact profile of the sink so that it can be slipped into the perfectly fitted opening with its top edge aligning perfectly flush with the surface of the countertop.
This particular option, however, should only be used with countertops that don't absorb moisture, such as stone countertops, due to a greater possibility of the sealed joint breaking down around the top.
Step 2 - Assessing your Resources
If the farm sink is being installed in an existing kitchen, built-in multi-drawers banks at either or both ends of the cabinet will significantly improve your chances of keeping the same cabinet by doing some alterations to its structure.
2.1 - Measure
Check the sizes for possibilities. Measure the full length of the sink, including the flanges, and bring that measurement to your cabinet to see if and how you can make it to fit between the two outside gables (sides) of the casework—the top drawers can always be removed, and the center walls cut down from drawer banks.
Suppose the cabinet is just too small to accommodate the farm sink. In that case, you'll probably need to remove that cabinet and the next one to create an appropriate free space where you'll be able to install an appropriate custom-built cabinet to accommodate the sink.
2.2 - Calculate
A new sink is usually supplied with the proper templates and directions for use. If you don't have the template, measure the width of the flange at each end and subtract both measurements from the full length measured in Step 2.1. This will be your minimum cutout length.
2.3 - Clear the Area
The doors, drawers, and dummy panels should now be removed from the cabinet to allow a clearer view of the inside.
Step 3 - The Countertop
3.1 - Mark Placements
Apply a piece of two-inch (50 mm) painter's tape on top of the counter along the front edge and trace a line on it to mark where the actual position of the cabinet's front edge is underneath. You can then transfer the "minimum cutout length" onto the tape to mark the sink's positioning.
Now step back and adjust the markings so that the sink will not get in the way of any plumbing or structural obstruction that doesn't absolutely need to be altered.
3.2 - Expand Marks
Once you've decided where the cutout starts, add two more pieces of tape from those marks at the front edge right up and perpendicular to the backsplash. You now have to add about 1/4 to 3/8 inches (6.0 to 9.0 mm) outside each of the two initial marks to make the opening wider and provide a final adjustment.
From those two new markings, with a carpenter's square placed against the front edge of the countertop, trace two perpendicular lines up to the backsplash.
3.3 - Mark the Total Shape
Determine the cutout depth by placing your measuring tape against the apron's flange and measuring all the way to the back edge of the sink. You can now measure the width (overlap) of the back flange and subtract it from the previous overall measurement to obtain your actual net cutout depth.
Transfer that dimension to each of the perpendicular tapes, measuring back from the cabinet's front edge and adding another 1/4 inches (6.0 mm) as for the sides. Place another tape right across to join those two last markings and trace a line on the tape to join them.
In each of the two corners of the layout, trace the approximate radius from the sink's back corners. This gives you the actual depth, width, and shape of the cutout.
3.4 - Drill and Cut
You can proceed to cut the countertop by first drilling a hole on the inside of one corner, large enough to accommodate the size of your jigsaw blade, and cut along the line at the back of the countertop.
A support piece should now be added and screwed to the scrap section of the cutout extending over the cut for supporting the weight once the section is cut. You can now proceed to finish cutting both sides down to the cabinet's front frame.
Bring the jigsaw against the front edge next, and proceed to cut as far as the cabinet’s front frame. The remaining portion on top can be cut by driving the jigsaw straight down through it.
Step 4 - Cabinet Modifications
If you have European style casework, you might be facing an opened front with nothing left to remove, in which case, you'll need to add a piece (on edge) wide enough to extend behind the sink’s apron at the top and about 1/2-inch (12 mm).
This will run behind the top of the doors and drawer fronts, framing the in-between gap with a remaining exposed surface of about 1-1/4 inches (32 mm) wide, fitting exactly between the two outside gables (sides).
Secure to the casework with angle brackets, then proceed with Step 4.1.
4.1 - Measure
To determine how much of the front needs to be removed, start by measuring the height of the apron, from underneath the sink's top to the outer edge of its bottom flange. From that measurement, subtract the width of the flange itself minus 1/4 inch (6.0 mm) for adjustments tolerance.
4.2 - Tape
Apply two pieces of two-inch (50 mm) tape under each of the edges created by the cutout, slightly longer than the drop of the apron. Measuring from the top of the cabinet's front, mark both vertical tapes on the front at the final dimension calculated in Step 4.1.
You can now use a straight edge to draw a horizontal line to join both of those marks. 3/4 inches (19 mm) lower than that line, draw horizontal guidelines inside each partition of the cabinet.
Finally, use a level to drop a vertical line from each extremity of the countertop cutout onto the front to intersect the horizontal line just drawn below. Both corners should be rounded with the proper radius before cutting and removing all the sections from the front inside the outline.
4.3 - Notch
With all obstructions removed, you will find that the cutout at the front edge of the countertop is not wide enough to let the full width of the sink apron drop into place to wrap over the front without notching it further.
The difference between that measurement and the full width is the overall amount to further remove, Notch half that amount at each location.
4.4 - Adjust Internal Partitions
If you have inside partitions, they'll need to be modified next by cutting them along the lower horizontal lines drawn in Step 4.2, then removing the top section(s) to finally clear the required space.
Step 5 - Framing for Added Support
Since this type and size of the sink can get quite heavy, we now have to make sure the wood structure is sturdy enough to carry it.
5.1 - Build First Braces
Going back to the horizontal guidelines on the outside partitions in Step 4.2, you now need to make two braces at 3/4 inches (19 mm) by about 3-inches (75 mm) wide to fit inside the space against each gable.
Place the pieces against the partition with the top edge lined up exactly on the guidelines and make sure to secure with 5-6 screws.
5.2 - Prepare Second Braces
Measure the distance between the two gables above the support braces and make two more pieces of that exact length from hardwood for added rigidity and strength, the same size or wider than the braces.
5.3 - Mark Measurements
Measure the center of the drain from inside the apron under the sink, and mark it on both braces from the front of the cabinet.
5.4 - Attach Crosspieces
Place those two crosspieces flat across the two gable braces and about six inches (150 mm) apart, centered with the drain mark, and screw them in place into the braces.
You now have two support pieces running across the length of the cabinet with about 1/4 inch space under the sink that will be used to add wedges for better support at the right places.
Note—You can also use heavier lumber to frame the braces, just remember that the guidelines on the gables will have to be traced lower to accommodate the sink.
Step 6 - Finishing Up
You can finally install your farmhouse sink, making sure it sits properly on its supports, and secure it in place with the proper fasteners and joint sealant.
The plumbing should be completed next, before proceeding to salvage whatever you can by resorting to your skills as DIYer to either resize or replace the doors and possibly put one or two drawers back into place, and maybe add a dummy panel where a drawer opening had to be cut down.
Every scenario has its own solutions, but after getting this far, you certainly have the vision to figure out and complete your masterpiece.