Cutting Door Into Lower Level Floor

Determine the underlying problem.

Cutting door into lower level floor.

Raise the lower end of the level until the bubble is centered then measure the distance from the bottom of the level to the floor to find the depth of the dip. Check the marks with a 4 foot level to ensure the lines are plumb and level. If you decide to cut off an exterior door make sure you have a plan for sealing the bottom of the door against the threshold when the door is closed. A plywood subfloor will bridge any minor waves in the existing floor and leveling compound would help too.

Use a piece of chalk to mark all obvious high and low spots on the floor. Hold a 16 inch long two by four block of wood vertical 4 to 5 feet up and centered in the doorway that will be cut out. Leveling a floor can be either a do it yourself project or a job for the pros. Drill two or three holes through the wood and into the foundation material with a hammer drill and a 1 4 inch diameter masonry bit.

Strip the frame down to the side 2 by 4 inch studs top header plate and floor or subfloor. Cutting a few inches from the top of the existing joists. In these situations lots of builders take the approach you mention. Remove any old door and molding such as a casing or bottom threshold inside the opening.

Glenn mathewson a code official in westminster colo responds. Before taking steps to level a floor you must find out why it s not level. You will have to make sure your joists can handle the addition of considerably more weight from the plywood subfloor and any floor coverings. Many new homes are built with lower profile joists to achieve this effect but that doesn t help much when it comes to remodels.

Sweep over the floor with a carpenter s level to reveal any depressions you may have missed. On the top side of the floor another fix it idea to lay down new hardwood over the existing floor.