What Is Rough Opening For Bifold Doors & How To Size It?

Each folding glass pane has a frame of its own, which, when closed, may result in a little obscured vision. In addition, bi-folds are usually fairly wide, making it challenging to measure them one by one. And, hence this article discusses the rough opening for bifold doors.

A bifold door or folding door opens by folding its panels or sections inside or outside. They have a minimum of two panels, and the number can be raised as the architect sees fit.

At the top, center, and bottom, measure the width of the aperture on three sides. Then measure the opening’s height three times, once in the center and once on each side. To determine your ultimate width and height, add one-half inch to each of the two dimensions with the least values.

Standard rough size of bifold doors

The average height of a bifold door is 6.67 feet, or 80 inches, from top to bottom. The widths will vary depending on how many door panels a homeowner desires. The normal bifold door width ranges from 28 inches (71 centimeters) to 39 inches (99 centimeters) for each door panel. For example, a homeowner with a 110-inch (279-centimeter) or larger aperture might fit three to four bifold doors.

Since bi-fold doors have limited limits for widths and heights, the best choice for broader panels is to go with custom ones. However, to ensure that the rough opening has adequate room to install the drywall, hardware, and jambs, it’s crucial to collect precise dimensions.

Most common size

The height of a conventional bifold door is 80 inches. Depending on the available space, the width of the door panels may change. Most apertures increase in size by 24-inch steps until they are 72 inches at most, or even more if necessary.

Dividend panel rough size

A bifold door’s panels are made up of uniformly sized pieces. For instance, a 48-inch bifold door, also known as a 4-O door, will have four panels, each 12 inches long.

Jambs or drywall rough size

Bifold doors are often installed straight to the walls. You are not prohibited from installing jambs, though.

If you intend to install jambs, ensure the anticipated rough opening is bigger than the opening for only the drywall to provide space for the jambs to be installed.

Drywall opening rough size

The drywall opening should be 48 inches by 82 inches if the necessary completed door opening is 48 inches by 80 inches. A rough opening should be 49 inches by 82 inches for a door that is 48 inches by 80 inches. 

As a result, the drywall will be 80 inches long to accommodate the hardware and doors, 1 to 1 1/2 inches thick on either side of the bifold door, and 1 to 1 1/2 inches above the door. In addition, the type of flooring used will affect the distance between the bottom surface of the bifold door and the floor.

Jambs opening rough size

The rough opening for a bifold with jambs is a little bigger to provide extra room for a door jamb on three sides. However, the height difference is negligible since it just adds a quarter inch. 

For a total thickness of 1 1/2 inches, including the 1/4 inch needed for shimming, door jambs are 3/4 inch thick. Therefore, a 48 by the 80-inch door with jambs would require a rough opening of 50 by 82 inches.

How to measure the bifold door opening?

This sort of door is affordable and very simple to install, but installation is only possible if you know the door’s required size. It just takes a few minutes and simple tools to measure for a bifold door, and it will help you acquire the door that best suits your needs.

Step1: Pick the Kind of Bifold Door You Want

Choose the type of bifold door you want. They may be constructed from various materials, including MDF, solid wood, or salvaged wood goods. Additionally, they come in various designs, including French doors with glass inserts and different types of paneling.

Your choice of the bifold door may affect how you measure the opening since various designs may call for different bracing spaces. This bracing gap might be anything between 6 and 12 inches. Bifold doors typically come in 24, 30, 32, and 36-inch widths. Any other size will require a specially constructed door.

Step 2: Calculate the door height

Place the metal edge of the tape measure on the ground at the bottom of the hole but inside the frame. The measuring tape should be pulled slowly upward until it reaches the top.

Note the number on the paper. For a typical bifold door, 80.75 inches are needed. You will need to pick another door style or have a bifold constructed if your aperture is bigger or less than this.

Step 3: Evaluate the door’s width

On one finished edge of the doorway, place the metal edge of the tape measure. Select a completed edge to start measuring with. Measuring from left to right, starting at the top left completed edge of the door opening.

To confirm that the aperture is square, measure the opening’s bottom similarly. You might need to make the aperture square if you want the new bifold door to fit.

Step 4: Calculate the Drywall Opening

You have now calculated the rough opening measurements for the door using steps 2 and 3. Next, add 2″ to the door height and 1″ to the door width to determine the drywall opening.

Step 5: Evaluate Jamb Opening

To achieve this, increase the door’s height and width by 2″ and 1″, respectively.

Step 6: Measure once more

Retake each measurement you took. It’s critical to take accurate measurements because even a minor error could result in you purchasing the incorrect door type and creating problems during installation.

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