How to Install Solid Core Doors

There are many great reasons to upgrade from hollow-core doors to solid doors, including quality, fire safety, and soundproofing. When a homeowner wanted to upgrade his hollow-core doors for something more substantial, he called the team at Ask This Old House for help, and master carpenter Nathan Gilbert answered.

How to Install Solid Core Doors

1. Start by measuring your existing doors. You can measure them in standard inches, width by height. But carpenters often refer to them by their feet and inches. For example, a 30-inch-wide door would be referred to as a ‘2/6,’ while an 80-inch-tall door would be referred to as a ‘6/8.’
2. Use a hammer and punch to remove the pins from the door hinges. Place the punch under the pin and tap it upward until it can be removed. Remove all three, but don’t lose the pins.
3. Remove the door from the hinges carefully. Use the screwgun and screwdriver to remove the door lockset and hinge leaves from the old door.
4. Place the new door down on the sawhorses. Next, place the old door with the hinges and lockset removed on top of the new door. Use a pencil and speed square to mark the location of the hinges and trace the lockset hole onto the new door.
5. Place the door down in a homemade door buck (which you can build with 2×4 scraps), hinge side up. Place the hinge jig on the edge of the door and fasten it to the door with screws or the built-in clamps.
6. Put on your safety glasses and hearing protection. With the templating bit in the router, route out the hinge mortises. They should be just deep enough for the hinges to sit flush with the door.
7. Place the lockset jig on the new door, aligned with the mark from the old door. Use the drill with the appropriate hole saw bit to bore a hole halfway through the door, until the pilot bit pokes out the other side. Stop, flip the door over, and finish boring the hole. Bore a hole for the latch, as well.
8. Place the latch mortise jig over the latch location and route it to the appropriate depth.
9. Place the hinges in their mortises. With the self-centering bit, drill pilot holes in each screw hole and install the hinge leaves with screws.
10. Lift the door into place (with help) and align the hinges and install the pins (bottom first).
11. Slide the latch into the hole and use the self-centering bit to drill the holes for the latch. Install the new screws and finish installing your lockset.
12. Open and close the door several times to test its operation, and enjoy a better-quality-feeling door with improved soundproofing.

Pro Tip: This Old House general contractor Tom Silva advises that a well-installed door should leave “about the width of a nickel” between the door and the jamb — just under 1/8 inch. Measuring and trimming the door before installation must be done carefully and precisely to achieve this gap.

Why bother with a slab swap instead of a prehung door? As This Old House carpenter Nathan Gilbert explained to homeowner Henrik during a recent project: if you get a prehung door, you have to pull the trim off both sides, throw away a perfectly good jamb, then put the new jamb in, shim it, trim it, and paint it. That’s a lot of extra work just to change the door slab. Swapping the slab lets you keep your existing jamb and trim intact.

Materials

• Solid core interior doors
• Homemade door buck
• Hinge jig
• Lockset jig
• Self-centering drill bit
• #2 Phillips screwdriver/ drill bit
• All purpose primer

What’s Inside a Solid Core Door: Unlike a hollow-core door — which has little more than veneer and strips of cardboard between its two faces — a solid core door has a strip of wood running down each side for securing hinges, with a core of compressed sawdust and resins. This construction gives the door real heft and significantly better sound insulation.

Tools