If a binding or sticking door doesn't respond to the quick fixes in Chapter 3, you'll likely have to reseat or shim its hinges. First, check whether or not the door is warped. Although you can try straightening it by removing it, laying it down, and weighting the warped area with heavy objects such as concrete blocks for a time, it may be easier and more effective to replace the door. If you are able to straighten the warp, be sure to seal all the door's surfaces, including the edges, to prevent moisture from seeping into the door and causing the warp to reoccur.

Reseating/Shimming Hinges

Ideally, a hinge plate should fit level with the surface into which its mortise has been cut. You can make adjustments to the hinge plates, however, to free up a binding door, as follows (in each case, you should be able to see which hinge would be the easiest and most effective fix):

• If the latch side of the door is too high, add depth to the bottom hinge, shims to the top hinge, or both.

• If the latch side is too low, add shims to the bottom hinge, depth to the top hinge, or both.

• If the frame side of the door is binding fairly evenly, shim out both hinges.

• If it's the latch side that's binding evenly, add depth to both hinges.

To add shims or depth to a hinge, first gauge the thickness of the shim or cut that you'll need to make. Push the door until it touches the frame, but don't force it closed. Measure the amount that the door is overlapping the frame; this is how thick your shim or how deep your cut needs to be.

To create a shim, unscrew the hinge plate. Cut a thin piece of wood, cardboard, or sheet brass to fit under the hinge plate, using the hinge plate as a pattern. Mark the screw holes on the shim, and use an awl to punch holes in them (or use a drill on the sheet brass). Reattach the hinge plate, placing the shim between it and the door frame.

To add depth to a hinge, unscrew the hinge plate, and use a wood chisel to cut pieces of the mortise away. Hold the chisel almost parallel to the mortise so that you're making very shallow cuts. When you get to the required depth, replace the hinge plate.

Silencing Squeaky Hinges

Squeaky hinges can often be fixed with a quick spray of penetrating oil into their tops. Move the door back and forth to work in the oil, and use a paper towel to sop up any excess oil. If that doesn't work, remove the hinge pin and clean it (sanding it down if it's rusty), then oil and replace it.

Misaligned Strike Plates

If a door is not latching properly, the strike plate (the metal plate on the door frame that the bolt goes into) may need to be realigned. First, tighten the door's hinge screws (Chapter 3) or reseat/shim any hinges (see the previous section) as required. If that doesn't solve the problem, look for scratches or damaged surfaces on the strike plate, to see where the bolt is actually meeting it.

For small misalignments (less than ⅛-inch), use a metal file to widen or lengthen the hole in the strike plate so that it will accept the bolt (it's easier to do this if you unscrew the strike plate first and clamp it in a vise while you file it). Then, use a chisel to widen or lengthen the hole in the door frame by the same amount.

For larger misalignments, remove the strike plate, and recut the mortise (the depression in which the strike plate sits) in the direction that the strike plate needs to be moved in order to meet the door properly. Use a wood chisel to cut pieces of the mortise away. Hold the chisel almost parallel to the mortise so that you're making very shallow cuts (it's better to make the cuts too shallow, rather than too deep). Then, cut or chisel out the bolt hole in the door frame to match the new strike plate position. Screw the strike plate into place, and use stainable wood putty to fill the piece of mortise that's now exposed.

A third option-if the strike plate is in the right location but is too far away from the bolt-is to remove the strike plate and use it as a pattern to cut out a shim from sheet brass, cardboard or thin wood. Replace the strike plate, with the shim placed between the door frame and the strike plate.

Trimming Door Bottoms

Occasionally, you'll need to trim the bottom of the door-for example, if you've changed the flooring, and the new surface is higher than the old one.

For a solid wooden door, measure how much material to remove, and transfer that measurement to the door by drawing a line across the door (run your pencil along a level or straightedge to create a straight line). Cut off the extra material using a power saw or a jigsaw. Sand the edges smooth, and refinish the cut edge to match the rest of the door (so that moisture can't enter the cut edge and cause the door to swell or warp).

A hollow wooden door is a little trickier. There's a piece of wood framing in the bottom of the door. If you need to trim just a little, you can handle it as though the door were solid wood. (To prevent the veneer from splintering, cut through it on both sides of the door with a utility knife before you make the saw cut.) If, however, you need to cut above where the wood framing is, save that framing once you've measured, marked the door, and cut off the excess. Rip or chisel off the veneer from the cut-off piece of framing, and run wood glue all around the framing. Reinsert it into the cut edge of the door, so that the framing supports the bottom edge of the door, and clamp it tightly while the glue dries. Seal all raw edges.