How to Build Your Own Cellar Doors

Making the Doors

1. Measure the opening. The doors will be installed on top of the frame so water will shed off the opening and onto the ground. Both doors must be the same height and width, with a 1/4-to-1/2-inch gap between them. Allow room for hinges on the side, but extend the top and bottom of each door to cover the frame of the opening. For this example, the doors will each be built at an arbitrary width of 24 inches and a height of 72 inches.

2. Lay out the 1-by-4 stock on the sawhorses and check each board for straightness. This is done by raising one end of the board to eye level and looking down the edge of the board. Twisted or bent boards should be discarded and used for another project. If the board is straight, cut one end square and then measure the length, beginning at the fresh cut. Mark the length and then make the second cut.

3. Cut four additional pieces of 1-by-4, each one at a length of 22 inches, ensuring that both ends are square.

4. Lay seven boards next to each other on the sawhorses and then place two horizontal braces at a distance of one foot from the top and bottom of the door. Ensure that one end of the brace is flush with the outside edge of the row of 1-by-4s.

5. Set two galvanized wood screws through the face of the horizontal piece and into the vertical slat that is located at the edge of the door. Then pull the boards tight and insert two more screws through the brace and into the vertical board located at the other outside edge.

6. Repeat this procedure for installation of the second brace.

7. Leave the other boards loose and with the help of an assistant flip the unit over so the braces are on the bottom.

8. Caulk each crack with exterior-grade white butyl caulk. Make sure you apply a continuous stream from top to bottom.

9. Take two pipe clamps and place one end of the clamp on the outside edges of the door. Pull the clamps tight against the outside edges.

10. Remove the screws from one end of each brace.

11. Pull the clamps tight so caulk oozes back out of each joint. Wipe the excess caulk up with a damp cloth.

12. Place screws in each board so that the screw joins the slat (vertical piece) to the brace. Each juncture of the vertical and horizontal boards should have three galvanized builder's screws.

13. Remove the pipe clamps.

14. Pull a tape horizontally across the face of the door (in two places) to mark the 24-inch point. Connect the two points with a chalk line and cut the door so that the width is exactly 24 inches.

15. Flip the door over; then cut and fit a 1-by-4 between the two horizontal boards as a diagonal brace. Screw this board in place and you can also add a few more screws to the horizontal braces.

16. Install an extra full-length vertical piece on one door, so it will cover the gap between the two doors. This piece should be full width and it should be attached to the face of one of the doors along the inside edge.