Drawer slides are a small but integral component of overall drawer function. If they become damaged or start to malfunction, they can significantly impact your drawer experience. Jammed drawers or difficulty sliding them in and out make using your cabinets frustrating and difficult. Replacing malfunctioning undermount drawer slides or upgrading the existing slides can improve your drawer function and make daily life a little easier.
In this guide, we’ll walk you through how to install undermount drawer slides, including the tools you need, how to adjust them properly, and the benefits of choosing undermount slides.
Note: If you’re interested in learning how to install side-mount drawer slides, read our guide.
Undermount drawer slides are a type of drawer slide that has a few different features that make them a good choice for kitchen, bathroom, and office cabinets.
Compared to side-mount drawer slides, undermount drawer slides are easier to install. Side-mount slides are installed on the cabinet and on the drawer, which means you have to get both pieces aligned correctly in order for the drawer to function. Undermount slides are installed by attaching clips to the bottom of the drawer and the glide to the inside of the cabinet. Once both are attached, all you have to do is slide the drawer onto the glides until the clips click into place.
Undermount drawer slides will typically be more expensive than side-mount glides, but they also offer greater functionality, like durability and adjustability. Because they’re hidden from view, they also offer a more streamlined and modern look.
Installing undermount drawer slides isn’t difficult, but it does take some planning to make sure you have the right tools and measurements. Gathering your supplies before starting the project can make the entire installation go smoother. Here are the tools and materials you’ll need to complete undermount drawer slide installation:
Before starting any project, it’s important to set up your workspace. Clear a counter or table, so you have a place to set the drawer. Gather all of your supplies and keep them within easy reach. Installation may take some trial and error, but following these steps will guide you through the process.
Getting the right measurements for dovetail drawers or other types of drawers will start this project off on the right foot. If you’re starting from scratch or upgrading all of the current slides, you’ll need to take a few different measurements. Keep in mind that this is a general guide. The actual measurements will be listed in the undermount slide installation guide as per the manufacturer.
The actual measurements will depend on the type of drawer you have and whether it has a face or is inset into the cabinet. Other factors that affect the measurements include the brand you choose, where it will be positioned, and whether or not you need to cut notches into the drawer. Follow the manufacturer’s instructions to make sure you’re taking the correct measurements.
Some manufacturers also make a jig that can accompany their undermount slides. Using a jig simplifies the process because you just set it in place and drill holes according to its template. If you don’t want to purchase the jig or the company doesn’t offer one, another option is to cut your own template that you can use over and over again. This is especially handy for attaching rear mount brackets or achieving the right spacing if necessary.
If the drawer slides came with rear brackets, measure for the correct position and then screw them into the rear of the cabinet. Alternatively, your cabinet might have stretchers in the front and back that allow the slide to rest directly on it. This allows for more accurate placement, as you don't have to measure the rear bracket location and ensure it's placed perfectly to receive the slide.
Start by marking the location of your drawer slide guides that you’ll install inside the cabinet. Follow the manufacturer’s instructions to determine the setback distance, so you know how far back from the front of the cabinet to position the slides. Depending on the type of cabinet you have, the slides may attach to the bottom of the cabinet, float between the front and rear, or sit on stringers.
In some cases, the drawer guide will attach to the back of the cabinet as well as the sides. Take accurate measurements to raise the undermount slides to the proper height and take time to double-check that your measurements are correct before you screw the guides into the cabinet.
To ensure proper spacing, you can use a spacer block that you screw to the cabinet. Then you would screw the slide to the spacer block. This is especially important for face-frame cabinets where the undermount slide will need to be installed in line with the drawer box rather than on the inside of the cabinet.
Next, you’ll install the clips on the front corners of the drawer. These clips attach to the slides and allow you to adjust the drawer after the slides are in place. For undermount slides, you’ll need to notch the back edge of the drawer to allow the slides to fit into the notch and sit flush with the bottom of the drawer. Before making any cuts, double-check the measurements based on the width of the slide to ensure you have the correct notch cut size.
After making any necessary cuts and installing the clips, insert the drawer onto the cabinet guide and push it all the way closed until the clips engage. Do a few tests by pulling the drawer out and then pushing it back in. If you installed soft-close or push-to-open drawer slides, test to make sure they’re functional.
Finally, there’s a small pin located on the back of the drawer slide. This keeps the drawer from tipping forward when it’s pulled out. If you haven’t already, mark the location of the pin on the drawer and drill a small hole using a 6mm bit for the pin to fit into.
After that’s done, it’s time to make any adjustments to the drawer’s position. The clips on the drawers double as a way to align the drawers. Using the cams on the clips, you can adjust the drawer up and down, right to left, and in and out to make sure they slide smoothly. Each manufacturer is a little different, so check the instructions, but it may take a little trial and error to get the drawers adjusted correctly.
Once everything is installed, test the drawer a few times by pulling it out and pushing it back in. Double-check to make sure all of the screws are tight and then put your items into the drawer. After using it a few times with the items in it, check the screws again in case any came loose with the first few uses.
There may be some issues that pop up either during installation or after you’ve used the drawer a few times. Let’s take a look at some common undermount drawer slide issues and how to easily fix them:
Installing new undermount drawer slides can mean more functional drawers that slide in and out smoothly. All you need is a few tools and a jig or two, and you’re ready to go. If you decide you want to have undermount slides professionally installed, we can help. At Eagle Woodworking, we offer undermount drawer slides, quality dovetail drawers, custom drawer inserts, and specialty drawers, so you can build the kitchen of your dreams with beautiful cabinets.
Undermount drawer slides can be easier to install than sidemount or roller slides because the rails click into the clips, and you don’t have to install them on the drawer itself. But you have to make sure your measurements are very accurate, so everything is positioned correctly.
Requirements for undermount drawer slides are highly dependent on the manufacturer and the drawer itself. Most importantly, you need to measure the drawer length as that will correspond to the slide length. You’ll also need to account for top-to-bottom clearance to make sure there’s enough room for the drawer to slide into the cabinet opening based on the drawer slide manufacturer.
The only tools you need for installing undermount drawer slides are a drill with a Phillips head bit and a self-centering drill bit. You can also use a jig to help make measurements easier and more uniform. If you need to cut a notch, you’ll also need a saw.
To determine the correct size of undermount drawer slides, you’ll need to measure the length, width, and depth of the drawer boxes as well as know the size of the sides.
Blum manufactures undermount drawer slides that are perfectly concealed under the drawers. The Blum MOVENTO and Blum TANDEM runners glide smoothly and offer the necessary strength and support to keep your drawers functioning properly.