Most suppliers offer a selection.
But getting the right configuration depends on your opening width, the clearance available on each side of the frame, and how you’ll actually use the space once the door is in.
This guide covers all the main options.
What “Configuration” Means for Bifold Doors – Guide by Edinburgh Bifold Door Professionals
Bifold door configuration refers to the combination of panel count, folding direction, traffic door position, and opening direction that determines how a set of bifold doors operates.
Each variable affects the others.
Add an extra panel, and the stack gets deeper. Choose a split-fold instead of a single stack, and you need clear wall space on both sides rather than one.
This is all affected on what material you use for your frame. For example, aluminium when compared to timber frames, are stronger. This means they allow for slimmer profiles and wider panels.
Getting the configuration right before ordering avoids compromises on your living once the door is fitted.
How Many Panels?
The number of panels is determined by the width of your opening.
Wider apertures support more panels, but the choice also affects how much wall clearance you need for the panel stack and where the traffic door can be positioned within the design.
Two panels
Two-panel bifold doors suit narrower openings and are a modern alternative to French doors or sliding patio doors.
Both panels fold to one side, giving a completely clear aperture when open.
There’s no traffic door on a two-panel set, so you either open the full run or not at all. Good for smaller rear openings where the full-width view is the priority rather than day-to-day garden access.
Three panels
Three panels give a comfortable opening for most rear extensions while keeping the panel stack manageable. One panel acts as a traffic door, letting you step in and out without unfolding the other two.
The stack folds to whichever side the traffic door is nearest.
Three panels are a popular choice where the opening sits between 1.8m and 2.5m wide.
Four panels
Four panels are among the most commonly specified configurations for rear extensions in Scotland.
Two panels can fold to each side in a 2-2 split, or all four can stack to one side where wall clearance allows.
A traffic door can be set within a four-panel arrangement, though the position within the panel run needs to be confirmed at the survey stage based on how the stacking is configured.
Five and six panels
Five-panel sets typically fold 3-2 or all five to one side. The 3-2 split balances the panel pack between both sides of the opening, which matters if wall space is tight on one side.
Six panels offer the same folding options with more glass: 3-3, 4-2, or a full single-stack.
At this width, a split configuration is often the more practical choice and reduces the depth of the panel pack on either wall.
Seven panels
Seven-panel configurations are used on wide openings where the bifold set spans a significant portion of the rear wall.
A 4-3 split is common at this size, with a traffic door set in one of the outer panels. Although this can split can be easily adapted to suit your lifestyle, with all seven going to one side also possible, as well as 5:2 and 6:1.
The wide opening that seven panels creates changes the relationship between indoor and outdoor space more substantially than any smaller configuration.
Folding Direction: Left, Right, or Both Sides
On a single-stack configuration, you choose whether the panels fold left or right.
This is driven by practical factors:
- where the wall clearance is
- which side the opening faces
- where you want the traffic door relative to garden patio
A split-fold divides the panels to both sides of the opening. This reduces the depth of the pack on each side and gives a symmetrical result when fully open.
Split-folds are often the better choice on wider five, six, or seven-panel sets where folding all panels to one side would create a deep, obstructive pack against the wall.
The Traffic Door
The traffic door, sometimes called the access door or master door, is a single panel within the bifold set that opens independently.
Rather than folding all panels back every time, you use the traffic door for everyday access to and from the garden without operating the full mechanism.
It has its own handle and locking system, separate from the main bifold multi-point lock.
The traffic door position within the panel run affects which way you approach the door from inside and outside.
Most homeowners have a strong instinct about where they’d prefer it once they think about day-to-day use.
Inward or Outward Opening
Bifold doors can be specified to open inward or outward.
Outward-opening is the more common choice in the UK because the panels fold away from the interior, leaving the room clear, and water running off the glass falls outside rather than onto the floor.
Inward-opening suits covered terraces or sheltered openings where space directly outside the door is limited.
In Scotland’s climate, where rain is rarely predictable, outward opening is the more practical default for exposed rear elevations.
Your surveyor will confirm which direction suits the specific exposure and layout of your opening.
Single-Stack and Split-Stack
Single-stack configuration means all panels fold to one side of the opening. This maximises the clear view and open feel on the non-stack side, but requires enough wall clearance to fit the full panel pack.
On a six-panel set, that pack can be 600mm or more deep.
Split-stack divides the panels between both sides. Less wall clearance is needed on either side, and the visual result when fully open is balanced.
On wider sets, split-stack is often the configuration that works best in practice and is the one most frequently specified for larger openings.
Low Threshold and Standard Threshold
The threshold is the section of frame at the base of the door opening.
Low threshold designs bring the bottom track as close to flush with the floor as possible, which reduces the step-over height and creates a near-level transition between inside and outside. Low threshold designs are made with accessibility in mind.
Standard thresholds sit slightly higher and offer better weather resistance in exposed locations.
In Scotland, where driving rain is common, your installer will advise on which suits the exposure level of your opening.
A well-fitted low threshold with proper weather sealing performs well in most residential settings, including properties in more sheltered positions.
Choosing the Right Configuration for Your Opening
The starting point to finding your perfect bifold doors is always the aperture width.
A surveyor measures the opening, checks wall clearance on each side, and assesses the elevation’s exposure before recommending a configuration.
From there, the main decisions are panel count, whether a split or single-stack fits the available wall space, and where the traffic door should sit relative to how you approach from the garden.
The threshold choice and opening direction are worth raising at the survey stage for any property in an exposed location.
There’s no single correct answer because the right configuration is specific to each opening.
A free home survey is the clearest way to work through the options for your space.
Bifold Doors from The Advanced Group
Don’t worry if you aren’t sure what configuration to go for, that’s exactly what are door experts are here to help guide you through!
The Advanced Group supplies and installs aluminium and uPVC bifold doors across Central Scotland, from two-panel sets to wide six and seven-panel to even wider configurations!
Every installation begins with a free home survey where our team measures your opening, advises on the right configuration, and provides a written quote with no obligation to proceed.
Call our Edinburgh team on 0131 370 0444 today and you can benefit for our 38 years of industry experience, alongside our 15-year guarantee!
