By Evan Christensen · Owner, The Barn Door Hardware Store
Published October 24, 2025 · Updated May 2026
Evan has owned and operated The Barn Door Hardware Store since 2016. "Double sliding door" is one of those terms customers use to mean several different things — biparting, bypass, and double bypass all involve two doors but work very differently. Getting the configuration right before ordering saves a lot of trouble. He and the team are available 7 days a week at info@thebarndoorhardwarestore.com.
"Double sliding door" is a description, not a specific product. Customers use it to mean different things: two doors that meet in the center, two doors that slide past each other, or two doors on parallel tracks. Each of those is a different configuration with different hardware, different sizing rules, and different tradeoffs.
This guide covers the three main configurations that involve two sliding door panels, what makes each one the right choice, and how to size each correctly. All hardware kits include track, rollers, hangers, floor guide, and mounting hardware — door panels are sourced separately.
Configuration 1: Biparting (two doors, one track, meet in the center)
Biparting hardware uses a single track. Two door panels each slide from opposite ends, meeting in the center when closed and sliding to each side when open. Each door needs clear wall space on its side equal to one door panel width.
This is the configuration most people picture when they think of a classic double barn door — symmetrical, equal panels that split from the center. It's a strong choice when you want visual symmetry from both sides of the opening and have adequate wall clearance on each side.
When biparting is the right choice
- You want a symmetrical two-panel look from both sides
- You have clear wall space on each side of the opening for each door to slide into
- The opening is wide enough that a single door would be too heavy or too large to operate easily
Biparting sizing
- Each door width: (opening ÷ 2) + 2 in — each panel overlaps 2 in per side
- Track length: 2× the combined door width (same as standard single track, sized to total panel width)
Browse our single track hardware — biparting uses the same hardware as standard single sliding, sized for two panels.
Configuration 2: Single bypass (two doors, one shared track, slide past each other)
Single bypass uses one shared track. Both door panels hang from the same rail and slide past each other through a telescoping mechanism. Pushing or pulling one door engages the other — both open and close together with one movement.
The telescoping action means the doors don't each need a full door width of clear wall to clear the opening — they bypass each other sequentially. This is the right choice when wall clearance is limited on both sides but you still need a wide opening covered.
Tradeoff: when closed, single bypass panels have a center overlap — 6 in for standard rollers, 9 in for spoke wheel rollers. The panels never sit flush against each other.
Single bypass sizing — 2 doors
- Door width (standard rollers): (opening + 10 in) ÷ 2
- Door width (spoke wheel rollers): (opening + 13 in) ÷ 2
- Track length for fully clear opening: 3× door width
Browse our single bypass hardware. Available in 220 lbs total system capacity, matte black and brushed nickel.
Configuration 3: Double bypass (two doors, two parallel tracks, independent operation)
Double bypass uses two parallel tracks mounted one in front of the other. Each door panel runs on its own track and operates independently — there is no telescoping link, so each door needs to be moved separately. The panels fully stack behind each other with no permanent center overlap when closed (plan for about 2 in of overlap per side, 3 in for bedrooms and bathrooms).
For pass-through applications — pushing both panels to one side to walk through — double bypass gives more usable clearance than single bypass. Because the panels fully stack behind each other with no overlap, you get more open space when the doors are pushed aside. Soft close is available on double bypass and not on single bypass.
Double bypass sizing — 2 doors
- Door width: (opening + 6 in) ÷ 2
- Track length for fully clear opening: 3× door width
Browse our double bypass hardware. Available in 220 lbs total system capacity, matte black and brushed nickel.
Which configuration do you need?
| Biparting | Single bypass | Double bypass | |
|---|---|---|---|
| Tracks | 1 track, 2 doors from each end | 1 shared track | 2 parallel tracks |
| Door operation | Each door slides to its own side | One push moves both doors | Each door independent |
| Wall clearance needed | One door width on each side | Less — doors telescope | Less — doors stack |
| Center overlap when closed | No — doors meet in center | Yes — 6 in or 9 in | No — plan for 2–3 in |
| Soft close | Available | Not available | Available |
| Best for | Symmetrical look, adequate side clearance | Limited wall space, convenience of one-door operation | Pass-through access, no overlap preferred |
For a deeper comparison of single vs. double bypass specifically, see our single vs. double bypass guide.
What's included in a hardware kit
All of our hardware kits include: track, rollers, hangers, track stops, anti-jump disks, floor guide, and all mounting hardware. Door panels are not included — we recommend sourcing your door locally from a lumber yard or millwork supplier, which is significantly less expensive than buying a kit that ships the door.
What kits don't typically include: handles (sold separately), a wall-mounted floor guide (if you can't drill into finished flooring), a trim clearance kit (if you have casing around the opening), and a latch. Plan for these before ordering to avoid a second shipment. Browse our accessories collection for the full range.
If you want the door panel and hardware together as one purchase, our complete barn door kits collection offers pine door and hardware bundles across several configurations.
Not sure which double door configuration fits your opening?
Email us at info@thebarndoorhardwarestore.com with your opening width, the wall clearance available on each side, and how the door is used — we'll confirm the right configuration and track length before anything ships. Available 7 days a week.
