How to Install a Bifold Closet Door Over Concrete

Install the overhead track onto the door header, which is the overhead horizontal portion of the door frame, inserting the screws with a power drill. Position the track about 1 inch away from the front of the door header.

Install the guide roller into the hole in the top of the lead bifold door. Tap it into position with a hammer. Install the top and bottom pivot pins into the top and bottom edges of the door. Tap the pins into position with a hammer.

Measure the correct distance from the side door jamb to the proper spot on the floor for the bracket, according to the door manufacturer's instructions. Use a tape measure, and make this measurement for each side jamb if you are installing two sets of bifold doors for the closet opening.

Position the string of a plumb bob in the center of the door's overhead track and hang the plumb bob straight down to the floor. Align the floor bracket so that its holes line up with the plumb bob's tip. By doing this, you make sure the bracket is aligned with the track above, and the door will be vertically aligned. A plumb bob is a metal weight, usually with a pointed tip, that hangs from a string. Do this for the floor bracket on both side jambs if necessary.

Install a masonry bit into a hammer drill. Wrap a narrow piece of tape around the bit to indicate the depth that you want to drill for the screw.

Mark through the bracket holes onto the floor, using a felt-tip pen. Move the bracket. Position the hammer drill over the marks and drill into the concrete, stopping at the tape mark on the bit. Remember to not exert force on the drill, simply hold and guide it down, allowing the drill to do the work. Also, occasionally pull back on the drill and extract the bit to prevent the buildup of dust in the hole.

Position the bracket on the floor over the drilled holes. Install masonry screws through the bracket holes and into the concrete to anchor the bracket. Use either the hammer drill or a regular drill.

Hang the bifold door. Place the top pivot into the hole in the bracket inside the overhead track. Lift up on the door and insert the bottom pivot into the floor bracket. Depress the door's guide roller and move the top of the door so that it is directly underneath the track. Release the guide roller so it pops up into the track.