How many gallons of paint do I need?
Standard paint covers about 350-400 sq ft per gallon. Use 350 for textured walls. Door area ≈ 21 sq ft, window area ≈ 15 sq ft. Dark-to-light color changes may need 3 coats. Primer is recommended for new drywall or dramatic color changes.
Calculate how many gallons of paint you need for your project. Enter room dimensions, number of doors and windows, and the number of coats. Get accurate paint quantity and cost estimates.
One gallon of paint typically covers 350-400 square feet with one coat. To calculate: measure the total wall area (perimeter times height), subtract doors (about 21 sq ft each) and windows (about 15 sq ft each), then divide by 350. Multiply by the number of coats needed — most projects require 2 coats.
Flat/matte finishes hide imperfections and are ideal for ceilings and low-traffic areas. Eggshell and satin offer slight sheen and are easier to clean — perfect for living rooms and bedrooms. Semi-gloss and gloss are highly durable and moisture-resistant, making them ideal for kitchens, bathrooms, and trim work.
Proper preparation is 80% of a good paint job. Clean walls with TSP or soap. Fill holes with spackle and sand smooth. Apply primer over dark colors, stains, bare drywall, or when changing from oil to latex paint. Use painter's tape for clean edges. Remove outlet covers and light switch plates before painting.
Cut in edges with a 2.5 inch angled brush before rolling. Use a W pattern when rolling to distribute paint evenly. Maintain a wet edge to avoid lap marks. Paint in good lighting to catch thin spots. Two thin coats are always better than one thick coat. Keep the room temperature between 50-85 degrees F for optimal drying.
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