DIY Skills & Techniques

Custom Moldings: Top Tips for Duplicating Interior Trim

Adding custom moldings? You can match your home's existing wall or ceiling trim or choose to create your own entirely original designs.


We may earn revenue from the products available on this page and participate in affiliate programs. Learn More ›

Molding profiles tend to represent eras in building design. As architectural details, moldings often serve to pinpoint a building’s place in time. Those who own period or historic homes often order custom moldings to maintain their home’s character.

Over the years, intricate moldings often indicated wealth and status. Money allowed for more custom work. However, the evolution of tools and materials has influenced how moldings are made, making complex profiles accessible to many budgets and project ranges.

Making Custom Moldings

Custom moldings can be obtained as original profiles or to match an existing profile. The first step in matching existing moldings is to remove a piece of the molding or make an exact trace or photo of it in place.

The process of recreating molding profiles is exacting and methodical. Typically, the sample is scanned in or the drawing recreated in a CAD (computer-aided design) software program. The CAD diagram then generates a code to drive numerically controlled machine tools such as a CNC template maker. The template maker produces a metal or, in some cases, plastic template. That template is then used in a profile grinder to produce molding knives to the specific shape and size of the desired profile cut. It is much like making keys, but it takes considerable skill and practice on the part of the machinist.

After the knives are ground, they are installed on a head molder. The molding material, whether it is eight feet or 5,000 feet, is sent through the knives and cut to specifications.

Custom Moldings - Installation

Custom vs. Stock Moldings

When comparing custom molding to “off-the-shelf” pieces available at retail outlets, Bill Hopkins, New England sales manager for Forester Molding and Millwork in Leominster, MA, says to take into account the craftsmanship and quality. “The number one advantage is that specially milled molding is custom,” he says. “The quality is twice as good. Everything that is custom is made fresh, ripped and milled into the desired profile. The detail is crisp.”

There are disadvantages, too, Hopkins says, starting with the fact that you can’t just go pick it up. “With most companies, it is 10 days to a two- to three-week turnaround.” Price can also become a factor. For custom molding, there is a setup charge that can range from $90 to $300. Even if only one piece is needed, that set-up charge is fixed.

Hopkins suggests that off-the-shelf moldings can vary from one piece to the next. Materials used are also more limited. Where retail yards largely carry pine molding, custom molding makers will typically carry poplar, which holds paint better, is a harder wood, and doesn’t dent. Mills can also work with specified and exotic woods.

Find trusted local pros for any home project

Working With a Specialist

When selecting custom molding, homeowners should consider working with a professional. An architect, interior designer, or sales manager from an experienced molding company can visit the job site, give profile recommendations, and suggest construction methods.

“We help guide customers through the right application,” says Jack Miller, millwork operations manager at Moynihan Lumber, in North Reading, MA. “If walls are not straight, we are going to point that out. We may recommend bringing a wall back to square or, as an alternative, padding and shimming. Old molding may have dipped or moved.”

Homeowners may want to think twice about taking on a custom molding project on their own because mistakes can be costly. Those who opt to install their own moldings may find off-the-shelf products easier to handle and replace.

Molding Cautions

For those considering recycling old moldings, Hopkins advises that paint stripping will leave the wood fuzzy, while scraping off the paint can ruin the profile. If the old moldings hold lead paint, it is critical to properly handle and dispose of this hazardous material.

Vinyl and polymer extrusion moldings are alternatives to custom moldings, but homeowners should check local building codes. According to Hopkins, polymer moldings can give off toxic fumes in a fire, so interior use may be limited. Hopkins also suggests that polymer moldings tend to highlight any imperfections in a wall.

Wood is prone to moisture damage and rot, however, so exterior use of polymer molding can be of particular benefit, says Miller. He describes the rear of one project home that was constantly subjected to low sunlight and high moisture levels. Any wood in these conditions would have problems over time, he says.

In that instance, solid pieces of dimensional PVC were glued together, as is done with wood, and run through the molder. It took on the same pattern as the wood molding, will take paint, and will never require the same maintenance as wood.