Paint Calculator for Doors
A whole-house door repaint uses 2-3 gallons of enamel, but a single front door fits in 1 quart. This paint calculator for doors splits your project into interior, closet, and exterior buckets because each uses a different coverage rate and may need a different paint type. The output tells you exactly how many gallons (and which type) to order.
How the Paint Calculator for Doors Works
The tool separates three categories because they have different paint requirements:
- Interior doors (bedroom, bath, hallway): both sides, interior trim enamel, 400 sq ft/gal coverage.
- Closet doors: usually painted on the hallway side only (the inside stays factory-primed or is hidden). Same interior enamel.
- Exterior doors (front, back, garage-to-house): both sides, exterior enamel with UV resistance, 300 sq ft/gal coverage and 10% more per coat because weathered surfaces absorb more.
Each door is 20 sq ft per side (3'0" x 6'8"). Panel and shaker doors add 15-20% to the paint area because the recessed panels and rails create more surface. Jambs and casing add 6 sq ft per door if you paint them.
Paint Needed for a Whole-House Door Repaint
A typical 3-bedroom / 2-bath house has about:
- 10 interior doors (bedrooms, baths, hallways)
- 4 closet doors
- 2 exterior doors
With 6-panel doors painted both sides (closets one side), 2 coats, including jambs: about 770 sq ft of paint area. That needs 3.2 gallons of interior enamel plus 0.8 gallons of exterior enamel. Round up to 4 gallons interior and 1 gallon exterior (or 3 quarts for exterior to save).
Paint Cost for Doors (2025)
| Brand | Product | Retail / gallon |
|---|---|---|
| Benjamin Moore Advance | Waterborne alkyd | $75-90 |
| Sherwin-Williams ProClassic | Acrylic enamel | $70-85 |
| PPG Breakthrough! | Urethane acrylic | $60-75 |
| Behr Alkyd Semi-Gloss | (Home Depot) | $50-65 |
| Valspar Signature | (Lowe's) | $45-60 |
At $70/gallon, a whole-house door repaint runs about $140 in interior paint plus $20 in exterior quart = $160 total, or $11-12 per door.
Quarts vs Gallons
A gallon covers 400 sq ft (interior) or 300 sq ft (exterior). A quart covers 100 / 75 sq ft. Here's when to pick each:
| Project | Paint needed | Buy |
|---|---|---|
| 1 door (both sides, jambs, 2 coats) | ~90 sq ft / 0.23 gal | 1 quart |
| 1 exterior door | ~95 sq ft / 0.32 gal | 1 quart |
| 3-4 interior doors | ~300 sq ft / 0.75 gal | 1 gallon |
| 8+ interior doors | 600+ sq ft / 1.5+ gal | 2+ gallons |
Quarts are almost always cheaper per project than gallons when you need less than 1 gallon, even though they cost more per ounce.
Interior vs Exterior Door Paint
Do not use interior paint on an exterior door. Interior enamel breaks down in 1-2 years outdoors due to UV and moisture. Exterior door enamel has:
- Higher binder solids (65-75% vs 45-55%)
- UV inhibitors (HALS and UV absorbers)
- Mildewcide
- Better adhesion to weathered or oil-primed surfaces
Products like Benjamin Moore Aura Grand Entrance, Sherwin-Williams Emerald Urethane Trim Enamel, and PPG Advantage Exterior are the standards.
Tips to Reduce Paint Waste
- Pull hinges and latch. Remove hardware before painting instead of taping around it. Less cutting-in means less waste and no drips.
- Lay the door flat on sawhorses. Runs and sags waste paint. Flat orientation uses less paint and looks better.
- Use a foam mini-roller for flat panels and a 2.5-inch angled sash brush for profiles. Both tools combined use less paint than a 4-inch roller alone.
- Between coats, wrap the brush and roller in plastic wrap. You can reuse them for 24 hours without washing. Big paint savings if you are doing many doors.
- Match sheen to use. Semi-gloss is standard for doors (easy cleaning, modest shine). Satin for modern flat-slab doors in bedrooms. High-gloss for traditional panel doors and exteriors. Flat paint never belongs on a door.