Question 1

How much paint do I need for a 12×12 room?

Accepted Answer

A 12×12 room with 8-foot ceilings has about 384 sq ft of wall area. After deducting a door and two windows, you need roughly 339 sq ft of coverage. With eggshell paint at 375 sq ft/gallon, that's about 2 gallons for two coats (including 10% waste).

Question 2

How many gallons of paint do I need per room?

Accepted Answer

Most standard rooms (10×12 to 12×14) need 1-2 gallons for two coats. A small bathroom may only need 1 gallon, while a large living room (16×20) could need 3-4 gallons. Always buy a little extra for touch-ups.

Question 3

Do I need primer before painting?

Accepted Answer

You need primer when painting over new drywall, bare wood, patched areas, or when making a dramatic color change (dark to light). If walls are in good condition and you're using a similar color, you can skip primer — especially with premium paint that has built-in primer.

Question 4

How much does it cost to paint a room?

Accepted Answer

DIY painting a 12×12 room costs $100-200 for paint and supplies. Professional painting runs $300-800 depending on your area. Paint costs $30-70 per gallon depending on quality and finish. Labor typically adds $2-4 per square foot.

Question 5

What paint finish should I use?

Accepted Answer

Flat/matte works for ceilings and low-traffic rooms. Eggshell is the most popular for living rooms and bedrooms. Satin is great for kitchens and hallways. Semi-gloss is best for bathrooms and trim. High-gloss is for doors and cabinets.

Question 6

How many square feet does a gallon of paint cover?

Accepted Answer

One gallon of paint covers 350-400 square feet on smooth surfaces. Flat paint covers slightly more (400 sq ft) while glossy finishes cover less (350 sq ft). Rough or textured surfaces reduce coverage by 10-20%. Economy paint may cover less than premium brands.

Question 7

How much paint do I need for a door?

Accepted Answer

A standard interior door (7' × 3') needs about 1 quart of paint per side for two coats — roughly half a gallon total for both sides. If you're painting multiple doors, add 0.5 gallons per door to your total. Use semi-gloss or high-gloss finish for doors.

Question 8

Should I include the ceiling in my paint calculation?

Accepted Answer

Include the ceiling if you plan to paint it the same color as the walls or a fresh white. Ceilings typically use flat/matte paint (400 sq ft/gallon coverage). For a 12×12 room, the ceiling adds 144 sq ft — about 1 extra gallon for two coats.

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