Compare common casing styles, mitered versus butted corners, standard widths, materials and outside cost benchmarks. Then follow the prep, priming and painting steps for a durable finish.
Interior door trim, called casing, is usually a three-piece frame around the door, with mitered or butted corners and a profile that matches your home's style and baseboard. Standard casing runs 2¼ to 3½ inches wide. It holds up best primed, then finished in semi-gloss or satin acrylic over sanded, caulked surfaces.
What are the common door trim styles?
Most casing is mitered or butted, then dressed in a profile. Metrie lists four popular styles: farmhouse, craftsman, minimal and colonial.
This Old House describes colonial casing as having a cove-and-bead profile, a subtle decorative detail that suits traditional homes. It calls fluted trim a quintessential Victorian style, with narrow ribs running the length of the boards, often paired with a more elaborate header. Minimal casing is flat and plain, and farmhouse is typically a wide, flat board.
Mitered or butted: how do the corners differ?
With mitered trim, the pieces meet above the door along 45-degree angled joints, and the casings look sharp and neat, so they tend to suit modern settings as well as rooms with lower ceilings. Butted trim sets the header square across the tops of the side pieces, which allows a wider, longer or more detailed head casing.
Bob Vila notes that builders designing for high ceilings often choose butted joints with a wide head casing. You can dress up either joint with decorative corner blocks called rosettes.
How do you match trim to your home, doors and baseboards?
Match the scale and era of the trim to the house. Sherwin-Williams points out that heavy Victorian trim does not suit a ranch-style home or an Arts and Crafts cottage, and minimalist trim lacks the impact a Victorian or Georgian design needs.
Casing boards taper, so one edge is thicker. Bob Vila explains that the thinner edge goes toward the door frame to reduce bulk, while the thicker outer edge matches the depth of the base trim for a cohesive threshold. If your baseboard is thick and tall, choose a casing that lines up with it instead of one that looks lighter than the base.
Match the casing to the window trim too. Metrie advises putting the most intricate, expansive trim on the interior side of the front entry door and scaling down for smaller doors.
What are standard casing width, thickness and reveal?
Standard width is 2¼ inches, and Angi says anything wider than 3½ inches must be custom-ordered. Its guidance is to pick a width by ceiling height and room size, so the trim looks proportionate next to surrounding trim and crown molding.
Use that as a rule of thumb. On lower ceilings, pick a mitered casing in the narrower range. On tall ceilings, go wider and consider a butted head. Thickness varies by profile, and the boards are milled thinner toward the jamb. There is no single reveal number, because the setback of casing from the jamb edge is set by whoever installs it and depends on the hinges and the profile.
Which trim material suits humid rooms?
Paint-grade wood, usually poplar or pine, arrives as bare wood that needs priming unless it comes pre-primed, per Metrie. Sherwin-Williams adds that MDF is less expensive than wood and hard to tell from the real thing once painted. It also lists high-density polyurethane as a lightweight, inexpensive alternative.
For baths and laundry rooms, moisture matters. Bob Vila says hardwood is the best option for areas exposed to moisture because it will not warp. Metrie makes the same point. In South Florida humidity, it's best to keep MDF out of baths, laundry rooms and any door that sees splashes, and use hardwood or a sealed, primed wood board there.
Benjamin Moore recommends Fresh Start High-Hiding All Purpose Primer on wood, MDF and vinyl trim. A moisture-resistant acrylic topcoat finishes the job. If trim in a humid room is already swelling, see the guide to repainting interior window trim in humid Florida homes.
How much does door trim material cost?
These are outside benchmarks from national publications, not PaintPro prices. They disagree because they cover different materials and widths.
| Material | Outside benchmark per linear foot | Source |
|---|---|---|
| Paint-grade wood | From about $0.75 | This Old House |
| Hardwood | Up to $10 | This Old House |
| MDF | $0.60 to $6 | This Old House |
| Paint-grade wood casing | $1 to $2.50 | Bob Vila |
This Old House adds that wider or more detailed trim costs more, whatever the material. Angi puts installation at about $0.60 to $1.20 per linear foot, and $100 to $170 to replace casing on a door. For a rough budget, a plain paint-grade board sits at the low end, and wide, detailed hardwood sits at the top.
For painting costs, see the interior painting cost breakdown.
What paint and sheen work best on door trim?
Use a durable acrylic in semi-gloss, or satin if you want a softer look. Benjamin Moore says satin, semi-gloss and high gloss are popular trim sheens, and that higher sheens offer more durability, stain resistance and washability in high-traffic areas.
Sherwin-Williams suggests flat walls with semi-gloss or gloss on trim and doors, because the eye needs a broad sheen difference to see contrast. In a single-color scheme, it recommends satin on trim and gloss on doors.
How do you prep and prime door trim?
Clean the trim, then sand any gloss. Sherwin-Williams advises that if there is a varnish or shine on trim or doors, you sand it or use a bonding primer, which is a primer made to grip slick surfaces. Benjamin Moore's guidance is the same: dull the old sheen, wipe with a damp sponge and let it dry.
Next, caulk the gap between wall and casing, and let the caulk cure fully before painting. Prime bare wood and every repair, and give heavily patched trim a full coat of primer. Skipping these steps is a common reason trim coats peel later.
How do you paint the trim step by step?
Paint after the ceiling and walls, working top down. Benjamin Moore's order is molding, window trim, door frames, then baseboards. The post on painting trim first or last explains why that sequence keeps drips off finished surfaces.
- Tape the borders against the wall, preferably over dry paint.
- Cut in with a small quality brush along the casing edges.
- Apply the first coat, let it dry, then lightly sand and apply the second.
- Paint the door, using the guide to spraying versus brushing interior doors.
If you would rather have a crew handle trim, doors and the prep in between, you can request a written quote for your interior.