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SlimFold

The Original Pre-finished Steel Bifold Door

SlimFold Doors are pre-finished and offered in four timeless designs that blend beautifully with décor. SlimFold is available in steel bifolds, mirror sliders, and furnace doors.

SlimFold: The Original Steel Bifold Door

Pre-finished in Five Timeless Designs
Available in Three Mirror Designs

Innovative Door Designs

SlimFold® is constantly innovating door designs. The furnace doors are perfect for laundry, furnace, or air handler (HVAC) closet doors. These doors are side-hinged full louvered doors constructed with 25 gauge cold rolled steel or A40 galvannealed Steel. Available in standard colors of Bright White, Ivory or Prime for field painting and are easy to install.

Slimfold® offers 3 outstanding and innovative mirror door designs, from sliders to bifolds and the new single panel overlay door. There is a design to fit every decor.

Safety

All mirror panels are 1/8” (3mm) float plate glass mirror with a laminated backing to prevent shattering (4mm on 7’0” heights and taller).

Installation

Installation is easy. With just a few tools and a little time, Slimfold® Bifold or Mirror Doors can transform a room from plain to beautiful. All hardware is included.

Durability

Slimfold® doors are engineered for beauty, quiet operation, and long life. They are carefully manufactured to provide years of maintenance-free use. The electrostatically-applied enamel is standard and galvannealed steel is available for areas of high humidity.

Classic

Flush

Lancaster

Louver II

Westchester – Now Available!

Finishes

SlimFold doors are available with a top-of-the-line factory prefinish.  Save time and money with a strong long lasting prefinished frame.  Choose from one of Dunbarton’s many standard colors or select a custom color of your choice. Mirrored Stiles and Rails are available in Bright White, Arctic Silver, Satin Silver, or Satin Chrome depending on your mirror choice.

SlimFold is finished in a state-of-the-art paint conveyor line with electrostatically applied, baked-on enamel.  This ensures complete coverage of the frame with a “best in the industry” paint finish.  No exposed edges of the steel or hardware cutouts compared to our competition.  Dunbarton also offers an option of A40 galvannealed steel that combined with our factory paint system gives maximum rust protection.

The Dunbarton factory-applied paint finish meets or exceeds the 500-hour salt spray test per ASTM–B117-97.  This is four times the requirement of hollow metal frames per SDI (Steel Door Institute) of 125 hours.

Dunbarton Painted finishes also passed a 700-hour humidity test per ASTM–D1735-87.

SLIMFOLD BIFOLD

Bifold:

Classic

Flush

Lancaster

Louver II

Westchester
Now Available!

Specifications:

• MATERIAL:
24 gauge cold-rolled steel with an alternate hot-dipped coating of zinc-iron alloy (galvanneal) recommended for coastal areas with high salt content
• REINFORCEMENTS:
Reinforced with 4″ wide stiffeners welded to banks and flanges of panels.
• HARDWARE:
All mounting hardware shall be factory installed. Rods to be zinc plated cold rolled steel with yellow dichromate finish. Patented weight-bearing pivot rods to be 9/16” (14mm) diameter, adjustable screw type, and securely held in position by nylon rod clamp assemblies. Guide rods and upper pivot rods shall be 1/4” (6mm) in diameter, spring-loaded for easy self-alignment, and securely held in position by self-retaining nylon sleeves.
• TRACK:
The top and bottom tracks are .055 mill finish aluminum. 

Bifold Diagram

Bifold Hardware

Track

Full Track

Bottomless

Specifications:

• MATERIAL:
16 gauge
• STANDARD:
Full track: Goes from wall to wall
• OPTIONAL:
Bottomless: L-Shaped Bracket attaches to wall and floor leaving open area in the middle.

Handles

4175 Pull Handle

Bifold Sierra Pull

Specifications:

• MATERIAL:
Chrome, Brass, Nickle  

Bifold Air Flow Chart

Door Width
Free Air Space Westchester 6’8″
Free Air Space Westchester 7’6″
Free Air Space Westchester 8’0″
Free Air Space LouverII 6’8″
Free Air Space LouverII 7’6″
Free Air Space LouverII 8’0″
3’0″
67 sq. in.
84 sq. in.
100 sq. in.
126 sq. in.
143 sq. in.
159 sq. in.
3’0″
67 sq. in.
84 sq. in.
100 sq. in.
126 sq. in.
143 sq. in.
159 sq. in.
4’0″
82 sq. in.
102 sq. in.
122 sq. in.
154 sq. in.
174 sq. in.
193 sq. in.
4’6″
82 sq. in.
102 sq. in.
122 sq. in.
154 sq. in.
174 sq. in.
193 sq. in.
5’0″
124 sq. in.
154 sq. in.
184 sq. in.
233 sq. in.
263 sq. in.
293 sq. in.
5’6″
124 sq. in.
154 sq. in.
184 sq. in.
233 sq. in.
263 sq. in.
293 sq. in.
6’0″
124 sq. in.
154 sq. in.
184 sq. in.
233 sq. in.
263 sq. in.
293 sq. in.

Mirror Styles

4050 Mirror - Steel Framed Sliding Mirror Door with Top Roller:

4050

4050 Cross Section

Specifications:

• STYLE DETAILS:
     Two panel configuration only. Top hung single sheep rollers for smooth and quiet operation. The snap-in bottom guides are virtually jump-proof.
• MATERIAL:
      Stile and rails are extruded anodized aluminum
• SIZE LIMITATIONS:
     Height: 6’8″,  7’0″, 8’0″
Width minimum: 36″
Width maximum: 80″
*Custom sizes available. Replacement panels available in 1 panel.
• MIRROR:
3mm safety-backed mirror standard, 4mm safety-backed mirror for heights greater than 7’0″ and widths greater than 3’0″.
• HARDWARE:
All mounting hardware shall be factory installed. Rods to be zinc plated cold rolled steel with yellow dichromate finish. Patented weight-bearing pivot rods to be 9/16” (14mm) diameter, adjustable screw type, and securely held in position by nylon rod clamp assemblies. Guide rods and upper pivot rods shall be 1/4” (6mm) in diameter, spring-loaded for easy self-alignment, and securely held in position by self-retaining nylon sleeves.
• TRACK:
The top and bottom tracks are .055 mill finish aluminum, prefinished to match doors.

4260 Mirror - Steel Framed Sliding Mirror Door with Bottom Roller:

4260

4260 Cross Section

Specifications:

• STYLE DETAILS:
      Two panel or three panel configuration. Adjustable top L-Guides for greater vertical adjustment allows for out-of-square opening adjustments.
• MATERIAL:
      Stile and rails are extruded anodized aluminum
• SIZE LIMITATIONS:
     Height: 6’8″, 7’0″, 8’0″
Width minimum: 42″
Width maximum: 96″
*Custom sizes available. Replacement panels available in 1 panel.
• MIRROR:
3mm safety-backed mirror standard, 4mm safety-backed mirror for heights greater than 7’0″ and widths greater than 3’0″.
• HARDWARE:
All mounting hardware shall be factory installed. Latch is adjustable ball tension catch at top. One piece 1-3/4″ deep top track and integral fascia.

4100 Mirror - Aluminum Overlay Door:

4100

4100 Cross Section

STYLE DETAILS:
     Available in both single and paired configurations. It overlays the door and does not require an exact fit. Features a magnetic catch system.
• MATERIAL:
      Stile and rails are extruded anodized aluminum
• SIZE LIMITATIONS:
     Width minimum: 16″
Width maximum: 36″
• MIRROR:
3mm safety-backed mirror standard, 4mm safety-backed mirror for heights greater than 7’0″ and widths greater than 3’0″.
• HARDWARE:
All mounting hardware shall be factory installed. Rods to be zinc plated cold rolled steel with yellow dichromate finish. 12 gauge pivot brackets eliminate track.

Mirror Diagram

4050 Diagram:

4100 Diagram:

4175 Diagram:

4260 Diagram:

Furnace Door Styles

Furnace Doors

Flush

Classic

250

325

325 Classic

500

Specifications:

• STYLE DETAIL:
     Smooth or textured finish available, no jamb required, and available in 20″, 22″, or 24″ width. All doors meet ventilation standards.
• RECOMMENDED USAGE:
     Model 100: Water heater or pantry area
Model 250/325: HVAC area; meets most HVAC free area space requirements
• MATERIAL:
24 gauge cold-rolled steel with an alternate hot-dipped coating of zinc-iron alloy (galvanneal) recommended for coastal areas with high salt content
• REINFORCEMENTS:
Reinforced with three 3″ wide, 24 gauge cold-rolled steel stiffeners, welded to back and flanges of the panel (12 welds per stiffener)
• FLAME SPREAD:
All doors meet requirements per ASTM E84-94 as tested by Warnock Hersey.
Model 250: Flame speed index= 0; Fuel contribution index= 0, Smoke developed index= 20
Model 325: Flame speed index= 0; Fuel contribution index= 0, Smoke developed index= 15
• HARDWARE:
Two hinges with six #8 wood screws, one-panel doorknob with a screw.
• INSTALLATION:
All HVAC/Furnace mount in finished opening with no frame required!

Furnace Door Water Heater

Furnace | Water Heater Air Flow

Door
Width
Door
Height
Finished
Opening Size
Free Air Space
Model #250
Free Air Space
Model #325
Free Air Space
Model #500
20″
78-1/2″
20-1/2″ x 80-1/2″
238 sq. in.
343 sq. in.
521 sq. in.
22″
78-1/2″
22-1/2″ x 80-1/2″
257 sq. in.
347 sq. in.
525 sq. in.
24″
78-1/2″
24-1/2″ x 80-1/2″
261 sq. in.
351 sq. in.
529 sq. in.

Colors

Colors may vary by screen! Color chips are available upon request. Click here to order.

Bypass | Swing Door Colors

Bright White

Ivory

Note: Leather “No Fingerprint” Finish Optional on all steel bifold doors.

Mirror Slider Colors

Bright White
4050, 4260

Artic Sliver
4050, 4260

Satin Chrome
4175

Satin Silver
4100

Primer*

Prime

**Prime Gray not intended for top coat. Primer not available for mirrors.

Technical Information

For a complete listing of technical data, click here.
For a complete listing of MSDS, click here.

Finished Openings SlimFold Mirror

Finished Openings SlimFold Bypass

Finished Openings SlimFold Bypass 4050

SlimFold 2 Panel

SlimFold 4 Panel

DUNBARTON WILL TAKE ON OPENING CHALLENGES

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