J Top Mount Heavy Duty Bifold Barn Door Hardware Kit | 8 Door Biparting

Panel weight: Up to 200 lbs per panel with the standard steel wheels. Eight panels works out to 1,600 lbs across the system, though that's the per-panel rating multiplied out rather than a separate limit. With the Delrin wheel upgrade, the limit is 100 lbs per panel — check your panel weight against that before selecting it.

Maximum panel size: 48 in wide × 108 in tall per panel.

Panel thickness: 1-3/8 in to 2-1/4 in. Because the hangers fasten to the top edge rather than through the panel face, one kit covers the whole range — there's no thickness variant to select. For thinner panels, 1-1/4 in to 1-3/8 in, standard duty is the right tier.

Wheels: Color-matched steel ships standard and carries the full 200 lbs per panel. Delrin is available as an upgrade for quieter operation, in black only, rated to 100 lbs per panel.

Panel width: Sized on total panel width — all eight panels combined — rather than the rough opening. See the sizing section below for formulas and worked examples.

Panel height: Opening height + 1 in. That leaves 5/8 to 1-1/4 in of floor clearance, adjustable at the wall-mounted pivots during installation — useful over uneven flooring or thick carpet.

Ceiling clearance above door: 6-1/2 in required between the top of the door panels and the ceiling — 1 in more than standard duty, because of the heavier pivot and hanger assembly. Measure before committing to a tier.

Wall clearance — both sides: Biparting needs clearance on both sides of the opening. For a fully clear opening, 10 in of clear wall on each side — four panels fold into two 2-panel folds, each 5 in deep. A minimum of 1/2 in is required between each track end and any adjacent wall or trim on the pivot sides, so the pivot panels can rotate freely.

Room depth on both stack sides: When the panels fold open they swing perpendicular to the wall, so each folded stack reaches into the room by the panel width plus 1/2 in — on 38 in panels that's 38-1/2 in per side. At heavy duty panel widths this is a substantial footprint on both sides. Check that nothing occupies either one.

Wall header: A 1×6 hardwood header board is the minimum for every installation — oak, maple, or poplar, not pine. It spreads the load and decouples the track's bolt spacing from your stud spacing, since the track's mounting holes rarely line up with studs. On a span this wide carrying panels this heavy, the header is the most important part of the install, and it must run continuously across every track joint. Extend it past the track to the next stud or structural support point on each side. Never mount to drywall alone. Ceiling mount is not compatible with bifold hardware, so a solid header is the only mounting route.

Trim beside the opening: Casing, baseboard, or other trim projecting up to 1/2 in is already handled — the kit ships spacers that stand the track off the wall, with nothing extra to buy. If your trim projects more than 1/2 in, email us with the measurement before ordering.

Origin: Colorado — made to order by Goldberg Brothers in Littleton

Lead time: 10-15 business days

Finishes: All 17 Goldberg Brothers colors

Weight capacity: 200 lbs per panel with steel wheels — 1,600 lbs across eight panels · 100 lbs per panel with the Delrin upgrade

Panel thickness: 1-3/8 in to 2-1/4 in — one kit covers the full range

Maximum panel size: 48 in wide × 108 in tall

Track lengths: 96 in, 112 in, 120 in, 128 in, 144 in, 160 in, 168 in, 192 in, 224 in, 240 in, 256 in, 288 in, 336 in, 384 in — this is your total panel width, supplied as one track per side

Track sections: Always ships in multiple sections with joining plates included — an 8-door needs at least 96 in of track, past the 7 ft 6 in single-section threshold

Hanger style: J top mount only — required for stacks of more than two panels per side

Hanger mount: Top edge of panel — no hardware on any door face

Wheels: Color-matched steel standard · Delrin available as an upgrade, black only, 100 lbs per panel

Track centerline height: Door height + 1-5/8 in + your floor gap (5/8 to 1-1/4 in) — unlike sliding hardware, the bifold figure doesn't already include the floor gap

Ceiling clearance: 6-1/2 in above door panels

Door-to-wall clearance: 1/2 in

Floor gap: 5/8 to 1-1/4 in — adjustable at the pivots during installation

Stack depth: 10 in per side, 1/2 in minimum at each pivot end

Pivot type: Wall-mounted sidewall bracket and plate — two sets included, one per side

Pull handles: Two 7 in pull handles included, one per side

Trim clearance: Spacers included — clears trim projecting up to 1/2 in

Soft close: Not available for any bifold configuration

Ceiling mount: Not compatible with bifold hardware

Returns: The listed track lengths are stock sizes and return under the standard window — 25 days from delivery with pre-approval and a 25% restocking fee. Designer colors are custom orders and can't be returned, which leaves 8 of the 17 colors returnable. See our return policy

Warranty: Limited lifetime warranty against manufacturing defects. Hardware is sold as rustic-finished, so minor marks and patina are characteristic rather than defects.

For bifold sizing across all six configurations see our bifold measuring guide. For general pre-order measurements see our measuring guide.

An 8-door biparting kit is two complete heavy duty 4-door stacks — one for each side — plus the alignment plates that join the two center panels. Each side has its own track, pivot, and hanger set.

• Pre-punched tracks (2), one per side, each half your total panel width — always supplied in multiple sections with joining plates
• Fixed top-mount hangers (2) · Loose top-mount hangers (4) — six hangers total, all attaching to the top edge of the panels
• 2-1/2 in wood screws for top-edge hanger attachment
• Hex bolts, 3/8 in spacers, and flange nuts for the roller assemblies
• Hinges (24) · 1 in hinge screws — four hinges at each of the six fold points, three per side, with three of the four used on panels 7 ft tall or under
• Sidewall brackets (2) · sidewall pivot plates (2) — one heavy duty pivot assembly per side
• Door bottom plates (2) · pivot pins (2) · 5/16 in lock washers (2) · 5/16 in nuts (2)
• Track stops (4) · rubber bumper bands (2) · felt strips (2)
• 5 in hex lag bolts, fender washers, and 1-5/8 in wood screws for track mounting — quantity scales with your track length
• 1/2 in and 1-1/4 in spacers for the track standoff
• Alignment plates (2) · wood screws (4) — for the two center panels
• Wrenches (2)
• 7 in pull handles (2), one per side

The fixed hanger on each side goes on the pivot-side panel. The two loose hangers per side travel freely as the panels fold. The alignment plates attach to the bottom of the two center-facing panels, holding them flush for a clean center seam when closed — set those panels edge to edge, either touching or with a gap up to 1/8 in.

Trim clearance spacers are included — 1/2 in and 1-1/4 in, for standing the track off the wall to clear projecting casing or baseboard up to 1/2 in. Nothing extra to select.

Fastener finish: clear zinc with Raw Steel, Silver Metallic, and PC Chrome; black oxide with Matte Black Texture, Bronze Texture, Black, and Arch Bronze; powder coated to match on the remaining ten colors — Jacob's Gold, Rustic Brown, Regal Red, Rocket White, Blue Ribbon, Flint Gray Texture, Dark Gray Texture, White Bronze Texture, Silver Vein, and Copper Vein. Because the hangers mount to the top edge, none of it lands on the panel faces. The lag bolts securing the tracks to the wall do sit on the track face and are visible after install, so on the seven finishes that don't ship matched, the touch-up paint option lets you paint them.

A latch and flush pull are not included — add them before ordering to avoid a second shipment. Soft close is not compatible with bifold hardware.

This kit includes two 7 in pull handles and trim clearance spacers for trim up to 1/2 in. A latch and flush pull are not included:

• Latch: Keeps the door closed deliberately — browse our latches collection
• Flush pull: For the wall-facing side if the doors are operated from both sides — browse our flush pulls collection
• Delrin wheel upgrade: Quieter than the standard steel wheels, black only, and limited to 100 lbs per panel — select it above if your panels are within that
• Touch-up paint: For painting the visible track bolt heads on finishes that don't ship matched — select it in the options above

8-door biparting sizing is based on total panel width — all eight panels combined — not the rough opening. The track length you select equals your total panel width, supplied as one track per side at half that length. For a full walkthrough of all six configurations see our bifold measuring guide.

Minimum coverage (doors close over the opening with a small overlap on each side):

Total panel width = opening + 4 in · Each panel = (opening + 4 in) ÷ 8

Example: 240 in opening → total = 244 in → each panel = 30.5 in

Fully clear opening (recommended — the panels stack entirely clear of the opening on both sides):

Total panel width = opening + 20 in · Each panel = (opening + 20 in) ÷ 8

Example: 240 in opening → total = 260 in → each panel = 32.5 in

The +20 in constant is the stack depth on both sides — 10 in per side. Because biparting splits symmetrically from the center, the installation looks balanced when open without extra sizing planning.

The track lengths listed in the options above are stock sizes, 96 in through 384 in of total panel width. They ship as ordered and return under the standard 25-day window. Note that 384 in is eight 48 in panels, this kit's maximum panel width and the widest span on the site — if your calculation runs past that, a 12-door configuration is the next step. Every length here ships in multiple sections with joining plates included, and your header board needs to run continuously across each joint.

Send us your numbers before ordering. At eight panels on a span this wide, panel sizing, track span, section joints, and header structure are all worth confirming — email info@thebarndoorhardwarestore.com with your rough opening width, panel material, and the wall clearance on each side, and we'll check it before anything is cut.

Goldberg Brothers hardware uses sealed bearings that run dry. Do not lubricate the track or rollers. Silicone spray, WD-40, and white lithium grease all attract dust, build up in the channel, and make the doors harder to fold, not easier. If the panels start to drag or squeak, the cause is almost always debris in the track or a pivot that needs adjusting — wipe the track channel with a dry cloth and check that the hardware is still tight. On an eight-panel setup, also check the hinge screws at all six fold points, since folding puts repeated load on them — and more so at these panel weights.