How to Tightly Fit an Antique Door
Ask This Old House general contractor Tom Silva uses multiple techniques to make an antique, drafty door weathertight
- Attach the plumb bob to the top of the door and pull the weight to the bottom of the door.
- Use a measuring tape to determine if there’s a difference between the distance of the plumb bob string at the top of the door and the distance from the string to the bottom of the door. If there is, the door is out of plumb.
- Remove the door from the hinges.
- To make the door plumb, hold a chalk line at the edge of the jamb on the end of the door that had the larger measurement. Put the other end of the chalk line at the other end of the jamb inward by the difference between the two measurements. Snap the string to make a line.
- Inspect the jamb and remove any nails.
- Chisel out any wood that lies outside the chalk line on the jamb. Smooth it out with a shoulder plane and a palm sander. Keep an eye out for any other nails that might have been missed to protect the chisel from being damaged.
- Repeat this process on the jamb on the other side of the door.
- Use the scribe to measure the distance between the hinge and other end of the door, and transfer that measurement to the jamb by holding the scribe against the new stop just chiseled out.
- Chisel out a new mortise for the door hinge based on the mark from the scribe.
- Drill new holes for the hinges and screw them back into the jamb.
- To make the door the correct length, make two rabbet cuts on each side of the bottom of the door.
- Attach two pieces of 1x6” lumber to the rabbeted door using wood glue.
- Instead of filling the gap in the middle, install automatic weather stripping to ensure a tight seal. Follow the instructions provided with the weather stripping to screw in the mounting bracket and slide in the weather stripping.
- Clamp everything together and allow the glue to dry.
- Once the glue is dry, cut the door to length and width using the track saw.
- Give the filler pieces on the door a good sanding with the palm sander.
- To make the filler pieces blend in with the rest of the door, use a utility knife and a speed square to extend score marks from the door to the filler pieces.
- Use the corner-grooving tool to cut into the corners on all sides of the jamb.
- Insert the corner-groove weather stripping into the channels.
- Rehang the door.
To fix the door, Tom addressed multiple issues: the door was out of plumb, it was too short, and it was drafty.
To make the door plumb, Tom used a plumb bob, a chalk line, a chisel, and a shoulder plane. These can be found at home centers. It’s also possible to use power tools to shave back the jamb, but hand tools will be required at the top and bottom of the door where those tools wouldn’t fit.
The tools Tom used to lengthen the door, including the wood, clamps, wood glue, and hammer, can also be found at home centers.
Tom also improved the weather stripping to make the door more weathertight. The automatic door bottom, the corner-groove weather stripping, and the corner-grooving tool and associated bits are all manufactured by Conservation Technology.