Years ago we removed all the carpeting in the house.
Extending the length of a door.
Place it in the center of the door at the bottom.
When you can see daylight under your door it is not the right size and needs to be.
This is the size of the gap but not the size of the extra piece you are going to need.
Clearance under the door.
The lines should extend from the floor to the ceiling.
Measure where the door meets the floor when it is closed.
For that you need to subtract at least a 1 8th of an inch for clearance.
Up from the floor at the high spot.
To seal out weather insects and dirt it is important to properly size your door.
The filler piece will be 1 1 2 in.
If there is carpet flooring remove a 1 4 inch space from the total measurement for easement from the carpet to the door bottom.
Measure the distance between the bottom of the door and the floor.
Make sure the door is closed and take out the measuring tape.
Tall and you ll want at least 1 2 in.
Make a light pencil mark on the door 2 in.
Remove the door by pulling out the hinge pins and lay it on a pair of padded sawhorses.
Any way to extend the length of the door replacing all the doors in the house would be to expensive.
Now we have a big gap from door to floor.
Draw vertical lines on one wall with a straightedge and pencil that are 6 inches or more from each outer edge of the door opening.