Don't despair! If your old house is missing a piece of one-of-a-kind molding, you can pay to have it replaced.

The problem is common to old houses, the intricate cap molding on the wainscoting in your dining room is intact -- except for the four feet the previous owner chopped out, to make an ugly metal cabinet flush with the wall.

Your renovation plans have no room for that metal cabinet, but the previous owner's idea of taste has created a gap in your plans. You check out the stock molding in your neighborhood lumberyard or the national home-center chain, and nothing comes close. When you ask, you are told that they don't make that style of molding anymore.

What's next? You can tear out the rest of the molding and start again, but that's the easy way out. If you want to do it the hard way and restore the missing piece, you do have a few options.

If you are able to find the right carpenter or contractor, he or she can try to match it up by making a custom molding. The carpenter can also remove the old moldings and install new ones. With wainscoting, a series of moldings actually works well. Usually, differences in molding styles are apparent only to a professional, a lot of people don't notice it unless you point it out.

If you are a homeowner and doing the work yourself, let me suggest cannibalizing the molding you need from less public areas of your house, such as a closet. I also recommend looking for a specialty lumberyard, where molding can be made to match or, where what you need might be in stock.

Research is necessary, as there are only a few specialty yards in each of the major metropolitan areas, usually in the older cities such as Boston, Philadelphia, Chicago, and Charleston. There are some across the country that advertise in magazines like Old-House Journal, these places have catalogues you can send away for.

There is always something that can be done, especially if you are willing to pay for it, and be prepared to pay. Even if you need just eight feet of molding, it will be expensive, due to the cost of setting up the machinery, and running the molding.

Why do we need molding? It's a good way to keep the bottom of a wall from getting banged up, plus, it also covers a lot of irregularities.

Once I pulled off the baseboard in an upstairs bathroom and discovered that the floor had been installed only up to the baseboard. Fortunately, I was installing a new bathroom floor, wainscoting, and new baseboard, so it didn't matter that much.

Molding also covers construction mistakes. You don't have to worry about rough framing, the molding will cover it.

The basic molding profiles used in America date to ancient times. During the Renaissance, books showed molding profiles from ancient ruins. In the 18th century, a lot of molding-pattern books were produced in England. The most influential pattern book in America around that time was The American Builders Companion, written by Asher Benjamin in 1806.

Until the early 19th century, there were eight different types of simple profiles based on Roman geometric patterns. These were made by carpenters using wooden molding planes that were run along strips of wood, thus producing the moldings.

By the mid-19th century, Greek elliptical shapes and mechanization appeared. Moldings became much more complex. Homeowners and contractors ordered moldings from catalogs.

Fewer molding profiles exist today because rising labor costs have made them more expensive, and that contributes to the replacement problems the old-home owner faces.

I had an interesting problem with molding on the exterior of one of my houses. A piece of crown molding had rotted out above one of the bay windows. When I took the piece to the lumberyard, I found that the new crown molding available could be trimmed slightly to match the profile of the older stuff.

What I didn't realize was the older molding was thicker than the new variety. To get the replacement section to match, I glued two pieces of new crown molding together, and then sanded it down until its thickness matched the old.

Although I mentioned making eight feet of molding, custom-molding sources typically will run no less than 400 feet. The cost of the molding is based on the price of the material, the cost of the cutter used to make the molding, and the time it takes to set up the cutting machine. The more molding you order, the more cost-effective it is.