How to Lay a Threshold on Concrete

Measure your old threshold's length and thickness. Measure the door opening from jamb to jamb. Close the door and measure the gap between the concrete floor and the door's bottom edge. Take all these measurements to the hardware store with you when you select your new threshold.

Lay the old threshold on the new threshold. Use a pencil to trace around the old threshold's edges to mark them on the new threshold. Cut the threshold along the marks. Use a jigsaw for wooden thresholds or a tin snips for metal thresholds.

Set the threshold into position on the concrete floor, between the side jambs. Some thresholds have predrilled screw holes while others are solid. If your threshold has predrilled holes, mark the holes' locations onto the concrete floor and remove the threshold.

Drill out the pilot holes with a masonry bit. Use a masonry bit that is equal in size to the anchors you will insert in the pilot holes. The anchor's diameter depends on the size of the supplied screws. Insert an anchor into each hole and hammer them flush to the concrete floor. Skip this step if your threshold does not have predrilled holes.

Insert a tube of construction adhesive into a caulk gun. Run two to three beads of adhesive down the threshold's length. Set it into place on the concrete floor, between the two side jambs.

Drive the supplied screws through the thresholds predrilled holes to secure the threshold in place. Skip this step if your threshold does not have predrilled holes.