Today’s aluminium bifold doors (more information here) are known for being convenient. They cover large openings and offer unlimited access to a closet.

The doors slide along a track set at the top when opening or closing them. If you’re planning to install bifold doors, it’s important to measure the rough opening for the doors.

white aluminium framed bifold glass doors design


The term rough opening refers to the vertical and horizontal measurements of a door or window opening before installing the drywall or siding.

It’s important to take accurate measurements to ensure that the rough opening allows for enough space to install the drywall, hardware, and jambs.


Common Rough Openings

A typical bifold door comes in a height of 80 inches. The width of the door panels may vary depending on the available space. Most openings graduate in increments of 24 inches to reach 72 inches at most or more if needed.


Drywall or Jambs

Typical bifold doors are fitted directly to the drywall. Nevertheless, you’re not restricted from installing jambs.

If you’re planning to install jambs, ensure the estimated rough opening is larger than the opening for the drywall alone to create enough room for installing the jambs.


Divided Panels

The individual panels that make up a bifold door have uniform measurements. For instance, a bifold door measuring 48 inches, also known as 4-O, will comprise of four panels each measuring 12 inches long.


Drywall Opening

If the finished door opening required is 48 inches by 80 inches, the drywall opening should measure 48 inches by 82 inches. A rough opening for a door measuring 48 inches by 80 inches should be 49 inches by 82 inches. As such, the drywall will have a thickness of ½ inch on either side and above the door, 80 inches to cater for the hardware and doors, and a space of between 1 inch to 1 ½ inch beneath the bifold door. The gap between the bottom surface of the bifold door and the floor will be determined by the kind of flooring in place.

Openings with Jambs

Rough openings for bifold doors that come with jambs are framed a bit wider to create enough room for the jambs. The height difference is insignificant. It’ll only add ¼ inch.

Typical door jambs have a thickness of ¾ inch and take up a total thickness of 1 ½ inch, including ¼ inch space for shims. A door measuring 48 inches by 80 inches with jambs will have a rough opening of 50 inches by 82 inches.


Taking Measurements from Scratch

  1. Drywall Opening

First, calculate the measurements for the door rough opening. To do this, add 2” to the door height and 1” to the door width.

  1. Jamb Opening

Calculate the measurements for the jamb. To do this, add 2” to the door height and 1” to the door width.

  1. A Single Size to Fit Both

In case you aren’t sure about installing jambs or drywall, you can opt for a bigger opening for the jamb. The difference will be insignificant and will make it possible to trim later on with any type of lumber or jambs.