How Much Paint do You Need? Picture Guide – Exterior + Interior

January 9th, 2018 | Chandler Zieg | Painting Business Articles | 37 Comments

We’ve painted over 2,000 homes and choosing the right amount of paint is still tricky. Paint is expensive and you don’t want to overbuy (paint stores will not refund an already tinted gallon of paint).

We recommend only buying about 80% of the estimated paint you need at first and then buying the remainder when you’re almost finished. This keeps you from overbuying paint.

However, sometimes you don’t have time to make 2 trips to the paint store and you have to take a leap of faith. This guide will help you decide how much paint you need:

Exterior House Paint

House Size Body Trim Total Gallons
1500 sq ft. 8 2 10
2500 sq ft. 12 3 15
3500 sq ft. 15 4 19
5000 sq ft. 20 7 27

Interior House Paint
You’ll use more interior paint in general because there is much more surface area inside a house than outside.

House Size Body/Walls Trim/Baseboards Total Gallons
1500 sq ft. 12 3 15
2500 sq ft. 18 4 22
3500 sq ft. 25 6 31
5000 sq ft. 35 8 43

Factors that can DOUBLE how much paint you need:

1. Surface type

A rough surface can double the amount of paint you need. Examples of rough surfaces:

Shingle/Shake Siding

Shingle_Shake Siding Pic

Stucco Siding

Stucco Siding Pic


Brick Siding Pic


2. How many coats?

If you want two coats on a house, you’ll need about 1.5x as much paint. Many people assume you’ll need twice as much paint, but since the first coat actually covers many porous areas that would normally soak up paint, the second coat uses far less paint.

3. Drastic change in colors?

Going from light to dark can really affect how much paint you need. It can sometimes take 2-3 coats to cover a much different color.

If your old colors and new colors are on opposite sides of a color wheel, you’ll need more paint.

4. Quality of paint

The quality of paint affects how much you need also. Higher-quality, expensive paints generally cover much better than cheaper paints. This is because cheaper paints have less resin (the main component that holds paint together).

Actual Houses We Painted and How Much Paint We Used

House Pic 1 (How much paint)

Gallons of Body: 15
Gallons of Trim: 3
Total: 18
Factors: This house was pretty big, but it was about 30% brick, so we didn’t need as much paint.

House Pic 2 (How much paint)

Gallons of Body: 12
Gallons of Trim: 2
Total: 14
Factors: Smaller to Medium-sized house but the wood was in rough shape so it used more paint.

House Pic 3 (How much paint)

Gallons of Body: 8
Gallons of Trim: 2
Total: 10
Factors: Smaller house that was about 30% brick.

House Pic 4 (How much paint)

Gallons of Body: 1.5
Gallons of Trim: .5
Total: 2.5
Factors: This room took 2 gallons total. A small bedroom like this usually takes no more than 1.5 gallons and then a half a gallon for the door and baseboards. The walls had a smooth surfaces as well (which uses less paint).

House Pic 5 (How much paint)

Gallons of Body: 16
Gallons of Trim: 3
Total: 19
Factors: This house was bigger and half of it was stucco.

House Pic 6 (How much paint)

Gallons of Body: 24
Gallons of Trim: 5
Accent Gallons: 1
Total: 30
Factors: This house took a lot of paint, mainly because we went from a light beige to the dark green in the photo. Big house + serious color change + lots of trim = a lot of paint.

Secrets to Using Less Paint and Saving Money

1. Replace Spray-Tips Periodically

An old spray tip uses much more paint than a brand new one. Once the tip wears out, the fan of the spray starts to blot in the center of where you’re spraying. This uses way more paint directly where you are spraying and leaves a weak, uneven coat on the edges of the spray fan.

2. Use a Quality Paint for Big Color Changes

We covered this a little earlier, but a drastic color change means you’ll need more paint. However, if you use a high quality paint sometimes you can get by with only 1 coat, which actually saves the total paint needed. You’ll still spend more on the paint, but you’ll save money on the labor side and your home will be better protected.

3. Bend Your Wrist as You Spray

It’s important to always be moving your arm/wrist when you’re spraying a house. Ideally you always want to be about 12-18 inches away from the siding at all times. Many people pull their arm away at the last part of the sweep, creating an uneven spray job and paint buildup in the middle.

4. Use Rollers Instead of Spraying

We get this question all the time: ‘Is it better to spray or roll your house?’ The answer is: it depends on what you want. Rolling a house uses less paint but actually covers the siding and trim better. Spraying doesn’t quite push paint into every crack like rolling does, but you’ll save a lot of money on labor, as rolling can take twice as long. You also get more protective paint on the house when you spray. So there is no clear answer on which is better, it just depends on what you’re looking for.

5. Only Buy 80% of What You Think You Need

Once you estimate how much paint you need, only buy 80% of that. When your closer to finishing, you’ll have a clearer idea how much you need left. This saves you from buying too much paint.

We hope this guide helped you. Now you can accurately estimate how much paint you need on a wide array of homes. Thanks for reading!

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