Floor Threshold

Tools:

work bench
scrap lumber
1x4 piece of oak (or other suitable hardwood)
circular saw
hand plane
orbital sander
sandpaper
clamps
combination square
hammer and nails
push drill
folding rule
pencil
silicone caulk
carpenter’s square
dust mask
safety goggles

1. Make a precise measurement of the doorway opening using the folding rule (figure A). Also measure the height difference between the two floors (figure B)

2. Use a seasoned hardwood such as white oak for your threshold. Cut the oak board to length using the carpenter's square as a guide.

3. Mark the line for the material to be cut away on the side of the threshold that will fit over the higher floor. Use a combination square to mark an even line along the length of the board (figure C).

4. Set the guide on your circular saw to make the cut. Also set the blade depth to the proper amount to cut away for the lip of the threshold. Clamp the threshold together with a piece of scrap lumber to create an area wide enough to support the saw (figure D).

5. Now turn the threshold on the side to cut away the lip. Nail the oak to a scrap piece of lumber to hold it in place temporarily. Drill pilot holes first with the push drill (figure E). These same holes will be used when installing the threshold, so be sure to position them symmetrically.

6. Set the saw blade depth so it just cuts away the excess material, and set the guide to follow the line. Cut away the excess material (figure F).

7. Remove the nails, flip the board over and reattach it to the scrap lumber with nails. Use the hand plane to shear away a nice bevel on each side (figure G).

8. Use the orbital sander to smooth out the piece (figure H). Remember to sand with the grain of the wood. Finish by sanding with a piece of fine-grit sandpaper.

9. Make sure the threshold fits in place (figure I), then stain it to match the adjoining floor. Attach permanently with screws. Run a bead of silicone caulk along the underside of each edge before installing permanently.