How Much Space Does a Concertina Door Take Up? Understanding Door Stack Width and Opening Sizes
How Much Space Does a Concertina Door Take Up When Open?
One of the most important questions to consider when planning an internal folding door or commercial concertina door is how much of the opening will still be available when the door is opened and stacked back.
Unlike a conventional hinged door, a folding or concertina door does not swing into the room. Instead, the panels fold together and move along a track, allowing the door to be positioned to one side of the opening.
However, the folded door panels still occupy some space.
The amount of space required depends on the width of the opening, the door configuration and the way the door is designed to stack.
For Australian Folding Doors systems, a useful general planning rule is:
-
Single-door configuration: approximately 13–14% of the opening width + 70mm for the stacked door.
-
Bi-parting pair: approximately 7–8% of the opening width + 70mm at each jamb, with the doors stacking at both ends.
These are useful planning figures, but the final stack dimension should always be confirmed for the specific project and door configuration.
For example, if a door is installed across a large room opening, you may want to know:
-
How much space will the folded panels occupy?
-
How much of the opening remains available?
-
Will people still be able to move through the opening comfortably?
-
Will equipment, furniture or stock need to pass through?
-
Is there enough room beside the opening for the stacked panels?
These questions are particularly important in commercial buildings, schools, community facilities, offices, clubs, hospitality venues and other high-use spaces.
The good news is that folding doors are designed specifically to minimise the amount of space occupied when open.
For more technical details and specifications of our acoustic and insulative accordion doors, please visit our Technical Information page.
What Is the Stack Width of a Folding Door?
Stack width refers to the width of the folded door's when it is opened and moved back to the side of the opening, while looking at it standing under the doorway,
This is important because if the concertina door's stack width is wider than the door jamb, then the installer would need to ensure there is enough clearance for the stack width, if it is jutting out from the width of the door jamb, that nothing is blocking the movement and parking of the door's stack, on either side of the opening.
This is especially important in tight builds such as:
- European laundries where the washing machine or dryers take up all the depth of the inside of the cabinet, and comes right to the doorway, and this may hinder the stack width from opening, closing or parking
- small pantries or built-in robes with shelves inside that come right up to the front of the opening and to the edge of the doorway's frame - again, because the folding door's stack width may be wider than the doorway's frame, they may come into contact with the shelves inside and this is an indicator that the folding door design is then not suitable for the design of the particular pantry or built-in robes
Australian Folding Doors' stack width is 180 - 190mm, and if a cavity or storage for the door stack is being planned, it should be at least 200mm wide to accomodate.
How Much Space Does a Single Folding Door Take Up?
For a single-door configuration, a useful general rule for our systems is approximately:
13–14% of the opening width + 70mm
This is the approximate amount of space required for the door to fold and stack back at the jamb.
For example, on a 5-metre opening: 5,000mm × 13–14% = approximately 650–700mm
Adding approximately 70mm gives a planning figure of around:
720–770mm of stack width.
The actual finished dimension can vary depending on the particular door design, panel configuration and project requirements, so this should be treated as a general planning guide rather than a final manufacturing dimension.
For a smaller internal opening, the same principle applies.
This is one reason why it is useful to consider the stack position before ordering the door, rather than simply measuring the opening and deciding where the door will go afterwards.
What About a Bi-Parting Folding Door?
For larger openings, a bi-parting folding door can be an excellent configuration.
Instead of all the panels folding and stacking towards one jamb, the door divides into two sections.
Each section folds towards its respective side of the opening.
For our systems, a general planning rule is approximately:
7–8% of the opening width + 70mm at each jamb
This means the stack is distributed between both sides of the opening.
For example, on a 10-metre opening, each side would generally require approximately:
10,000mm × 7–8% = 700–800mm
plus approximately 70mm.
That gives a general planning figure of around 770–870mm at each jamb.
The advantage is that the door does not create one large stack at a single side of the opening.
This can be particularly useful for large commercial openings, where maintaining good access through the centre of the opening is important.
Single Folding Door vs Bi-Parting Pair
The choice between a single door and a bi-parting pair is not simply about the size of the opening.
It can also come down to how the room will be used and what you want to happen when the door is open.
Configuration: Single Door
General stack allowance: 13–14% + 70mm
Typical consideration: Panels stack at one jamb
Configuration: Bi-parting pair
General stack allowance: 7–8% + 70mm at each jamb
Typical consideration: Panels divide and stack at both jambs
For a smaller opening, a single folding door may be the simplest solution.
For a very wide opening, splitting the door into two bi-parting sections can provide a more balanced arrangement and help preserve access through the opening.
How Wide of an Opening Can a Folding Door Close?
Another common question is: “How wide can you actually make a folding door?”
There is no single answer that applies to every folding door because the practical maximum depends on the door system, configuration, opening, application and supporting structure.
However, Australian Folding Doors has manufactured bi-parting folding door systems up to 15 metres wide - mainly for commercial applications, but also for dividing large internal residential spaces such as private entertaining / performing spaces or large garages.
That makes folding doors suitable for much larger openings than many people initially expect.
A large folding door can allow one room or space to be divided when required, then opened when a larger continuous area is needed.
This can be particularly useful in:
-
school classrooms
-
community halls
-
sporting clubs
-
function rooms
-
commercial offices
-
training rooms
-
meeting spaces
-
hospitality venues
-
healthcare facilities
-
large residential entertaining areas
For very large openings, the conversation should move beyond simply asking “How wide is the opening?”
It is also important to consider where the door stacks, how the opening is supported and how the space will be used.
What Is the Smallest Folding Door Opening?
Folding doors are not only for enormous openings.
Australian Folding Doors has manufactured single-door configurations as small as approximately 1.1 metres wide.
There is an important reason for this minimum.
When a folding door is opened, some of the opening is occupied by the stacked panels.
On a very narrow opening, this can leave too little clear space for people or objects to pass through comfortably.
For this reason, the practical minimum opening width needs to consider the clear opening remaining after the door has been stacked, rather than simply asking whether a folding door can physically be manufactured at a particular width.
A 1.1-metre minimum for our single-door configuration helps provide a useful balance between having a folding door and still retaining sufficient usable passage width when the door is open.
Why Clear Opening Width Matters
This is an important distinction that is sometimes overlooked when planning a folding door.
There is a difference between:
Overall opening width
and
Clear opening width when the door is stacked open.
If you have a 3-metre opening, for example, you cannot necessarily assume that the entire 3 metres will remain unobstructed when the folding door is opened.
Some of the opening will be occupied by the folded panels, or what we call "The Stack".
If space or design allows, a "cavity" or storage space for the stack can be created, and for Australian Folding Doors' design, this storage space would need to be 200mm at the minimum, to accommodate the 180 - 190mm stack width.
This matters particularly where the opening is used for:
-
regular pedestrian traffic
-
moving furniture
-
moving equipment
-
wheelchairs and mobility aids
-
trolleys
-
stock movement
-
machinery
-
deliveries
-
school activities
The door should therefore be designed around how people and objects actually use the opening, rather than simply the physical dimensions of the room.
How Do You Choose Between a Single and Bi-Parting Folding Door?
A useful starting point is the width of the opening.
Smaller openings
A single folding door will often be the simplest configuration.
The door folds and stacks towards one jamb, keeping the installation relatively straightforward.
Larger openings
For wider openings, a bi-parting configuration can make more sense.
The door divides into two sections, with each section stacking towards an opposite jamb.
This distributes the stack space and can provide a more practical arrangement for large rooms.
High-traffic openings
Where people regularly move through the opening, it is especially important to consider the clear passage remaining when the door is open.
This is one of the reasons we don't recommend simply choosing a door based on the overall opening width.
It also matters where certain semi-permanent or permanent fixtures are in the way where the doors are to be stacked - if there are electrical fixtures, cabinetry, etc on either side of the jamb that may interview with the stack parking cleanly and nicely without obstructions at the jambs, then a different configuration or jamb where the door stacks may have to be considered.
What Else Needs to Be Considered Besides Width?
Opening width is only one part of planning a folding door.
Before manufacturing, we also recommend considering:
1. Opening height
The finished height affects the door design and the supporting track arrangement.
2. Head support
The folding door track needs suitable support above the opening.
This is particularly important in commercial applications and openings beneath suspended ceilings.
3. Floor conditions and type
Existing floors are not always perfectly level.
Depending on the system, sweep seals can help accommodate variations in floor level while maintaining contact with the floor.
At times doorways are the place where transitions between floor types happen - carpet to tiles, etc, and these transitions are not usually level and of the same height - this is where our expert advice on concertina doors (Contact us here for advice) comes in and can ensure a good fit when the door is manufactured and fitted.
4. Where the door will stack
Think about what is beside or on either side of each jamb.
Will the stacked door interfere with:
-
another doorway?
-
shelving?
-
cabinetry?
-
equipment?
-
signage?
-
walkways?
-
furniture?
5. How the room will actually be used
A door separating two classrooms may have very different requirements from one dividing a commercial function room or a residential entertaining area.
The purpose of the room separation should influence the door configuration.
Can Folding Doors Be Used for Very Large Rooms?
Yes.
Large folding doors can be a practical way to divide spaces that need to operate differently at different times.
A large room might be used as one open area during a function, meeting or event.
At another time, the same space might need to become two or more smaller areas.
Rather than permanently constructing a wall, a folding door allows the space to remain flexible.
This is one reason folding and concertina doors are commonly considered for schools, community buildings, sporting clubs, commercial fitouts and function spaces.
For particularly large openings, a bi-parting arrangement can provide a practical way to divide the door into two manageable sections.
For an example of how we used our accordion doors in a large area - refer to case study of our client in Hobart who used our concertina doors to divide a large hall to let more groups use it at the same time for multiple bookings and events.
What About Residential Folding Doors?
Folding doors can also be useful in residential applications, particularly where the opening is relatively large or where flexible room separation is important.
Examples include:
-
large living areas
-
home offices
-
studies
-
entertaining spaces
-
kitchens
-
servery openings
-
garages and workshops
-
large open-plan areas
For a smaller residential doorway, a conventional hinged or sliding door may sometimes be more appropriate.
For a larger opening where flexibility is the priority, however, an internal folding door can be a very effective option.
The important question is not simply “Can a folding door fit?”
It is:
“What configuration gives us the best usable opening when the door is both closed and open?”
Planning a Folding Door? Start With the Opening, Not Just the Door
When planning a folding or concertina door, it is tempting to start with the product.
A better approach is to start with the opening.
Consider:
How wide is it?
How high is it?
Where should the door stack?
How much clear opening do we need when it is open?
What will pass through the opening?
Does the head have suitable support?
Will the door be used for visual separation, thermal separation, acoustic separation or simply to divide a large space?
Once these questions have been answered, it becomes much easier to determine whether a single folding door, bi-parting pair or another configuration is appropriate.
To get a better idea of how to measure the opening height and width, please refer to our guide on measuring for concertina folding doors.
Australian-Made Folding Doors for Internal & Commercial Applications
Australian Folding Doors manufactures folding and concertina door systems in Melbourne and supplies projects Australia-wide - from Brisbane to Darwin, to the shticks and mines.
Our doors are made to suit the individual project rather than relying solely on standard stock sizes.
We've supplied folding doors for applications ranging from relatively small internal openings through to 15-metre-wide bi-parting systems.
For larger projects, we can work through the opening dimensions, intended use, stack requirements and installation considerations to help determine the most suitable configuration.
Whether the requirement is for an internal residential application or a large commercial room divider, the opening and the way the space will be used should drive the design.
Frequently Asked Questions
Q: How much space does a concertina door take up when open?
A: As a general planning rule, our single-door folding systems require approximately 13–14% of the opening width plus 70mm for the stacked door. For a bi-parting pair, approximately 7–8% of the opening width plus 70mm is required at each jamb.
Q: How wide can a folding door be?
A: Australian Folding Doors has manufactured folding door systems up to approximately 15 metres wide using a bi-parting configuration. The appropriate configuration depends on the opening, application and supporting structure.
Q: What is the minimum width for a folding door?
A: Our single-door configurations can be manufactured from approximately 1.1 metres wide. This minimum helps ensure there is still sufficient usable opening width when the folded door is stacked.
Q: Do bi-parting folding doors take less space?
A: A bi-parting pair does not necessarily require less total space, but it distributes the stacked door between both jambs. As a general planning rule, each side requires approximately 7–8% of the opening width plus 70mm.
Q: What is the difference between stack width and clear opening?
A: Stack width is the amount of space occupied by the folded door when open. Clear opening is the usable passage remaining after the door has been stacked.
Q: Can a folding door be used for a large commercial opening?
A: Yes. Folding doors can be manufactured for large commercial openings, including bi-parting configurations. Australian Folding Doors has completed systems up to approximately 15 metres wide.
Q: Do I need to consider the structure above the opening?
A: Yes. The folding door track requires suitable support above the opening. This should be considered during the planning stage, particularly for commercial projects, suspended ceilings and large openings.
Final Thoughts
Thinking About Making Better Use of an Existing Commercial Space?
Australian Folding Doors works with businesses, schools, community organisations, builders and commercial fit-out projects across Australia to help determine whether a folding door system is suitable for the space.
If you're planning a commercial renovation or need to divide an existing room, get in touch with Australian Folding Doors to discuss your project.
