Drawer Slide Types
There are five main types of drawer slides: side-mount ball-bearing, undermount, center-mount, roller and wooden runners. Side-mount ball-bearing slides are the common choice for home-built drawers: they need 1/2 in (12.7 mm) of space on each side of the drawer, open fully and carry 75–100 lb (34–45 kg). Undermount slides hide under the drawer and close softly, but need a drawer built for them. To fit them, see how to install drawer slides.
The slide types compared
| Type | Space per side | Extension | Typical load | Best for |
|---|---|---|---|---|
| Side-mount ball-bearing | 1/2 in (12.7 mm) | Full | 75–100 lb (34–45 kg) | Most cabinets and DIY drawers |
| Heavy-duty side-mount | 1/2–3/4 in | Full or over-travel | 100–500 lb (45–225 kg) | Files, tools, pantry pull-outs |
| Undermount (concealed) | about 3/16 in (5 mm) | Full | 75–130 lb (34–60 kg) | Kitchens, quality furniture |
| Roller (bottom-mount) | 1/2 in (12.5 mm) | 3/4 | 35–55 lb (15–25 kg) | Light drawers, flat-pack |
| Center-mount | 1/8 in or less | 3/4 | 25–35 lb (11–16 kg) | Old face frame cabinets |
| Wooden runners | 1 mm or less | 3/4 or less | Depends on the wood | Traditional furniture |
Load ratings are for a pair of slides at full extension; each maker publishes its own.
Side-mount ball-bearing slides
Two steel members, one on the cabinet and one on the drawer, run on ball bearings. They tolerate small errors, are easy to fit with a spacer board, and come with full extension, soft-close or push-to-open. The slide is visible on the side of the open drawer. Build the drawer box exactly 1 in (25.4 mm) narrower than the opening.
Undermount slides
The runners sit under the drawer, hidden from view, and usually include soft-close. The drawer must match the slide: sides no thicker than 5/8 in (16 mm), the bottom recessed 1/2 in (13 mm) from the bottom edge, a notch at the back and holes for the locking clips. The box length must equal the slide length exactly.
Roller, center-mount and wooden runners
Roller slides are epoxy-coated steel channels with nylon wheels, screwed under the bottom edges of the drawer. They are cheap and quick but open only three-quarters of the way and can rattle. Center-mount slides run on a single rail under the middle of the drawer, mostly in older cabinets. Wooden runners are strips of hardwood in grooves, waxed to run smoothly: they need careful fitting and suit traditional furniture.
Slide lengths
Measure the inside depth of the cabinet, from behind the face frame (if there is one) to the back panel, take off about 1 in (25 mm) and round down to the nearest slide size:
| Inside depth of the cabinet | Slide length |
|---|---|
| 13–14 in | 12 in |
| 17–18 in | 16 in |
| 19–20 in | 18 in |
| 21–22 in | 20 in |
| 23–24 in (standard US base cabinet) | 22 in |
| 330–379 mm | 300 mm |
| 430–479 mm | 400 mm |
| 480–529 mm | 450 mm |
| 530–579 mm (560 mm carcass) | 500 mm |
Features to choose
- Extension: three-quarter, full (the whole drawer comes out) or over-travel (an extra inch, for drawers under a countertop overhang).
- Soft-close pulls the drawer shut gently; push-to-open lets you skip handles.
- Disconnect lever: lets you lift the drawer out to clean or fit it.
To size the drawer boxes for each slide type, see how to build drawers.
Frequently asked questions
What are the main types of drawer slides?
Side-mount ball-bearing slides, undermount (concealed) slides, center-mount slides, roller (bottom-mount) slides and wooden runners.
What size drawer slides do I need?
Measure the inside depth of the cabinet, take off about 1 in (25 mm) and round down to the nearest size: slides come in 2 in steps from 10 to 28 in, or 50 mm steps from 250 to 650 mm.
How much clearance do drawer slides need?
Side-mount ball-bearing and roller slides need 1/2 in (12.7 mm) on each side of the drawer. Undermount slides need about 3/16 in (5 mm) per side.
Are undermount slides better than side-mount?
They look better, are hidden when the drawer is open and usually close softly, but they cost more and need a drawer built to their specification. Side-mount slides are cheaper and forgiving.