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Quick answer: Painting the exterior of a one story house usually takes somewhere around 10 to 18 gallons total for two coats, split roughly into 8 to 14 gallons for the siding body and 2 to 4 gallons for the trim, fascia, soffits, and doors. That is a planning range, not a fixed number. Exterior gallons swing enormously with your siding texture, because rough or porous surfaces drink paint far faster than smooth lap siding. Measure the actual walls, do the coverage math below, and buy about 10 percent extra for touch-ups and the odd thin spot.
Here is the key idea that trips people up on exterior jobs: the gallons you need are driven by your siding area and its texture, not by the floor area of the house. A one story home spreads its living space across a single level, so it has roughly one band of siding wrapping the perimeter. That band, its height, and above all its surface texture decide how much paint you buy. This guide shows you how to size that band, walks the coverage math, gives you a gallons table, and works a full example. For the dollars side of the same job, see our companion guide on the cost to paint a one story house exterior, and for the whole-home framework, start with our hub on how much paint for a house exterior. To turn gallons and hours into a real number, run it through the painting cost calculator or grab a free painting estimate.
What drives exterior gallons
Exterior paint quantity comes down to two things: how much siding you have and how thirsty that siding is. The siding area, sometimes called the body area, is the wall surface you actually roll and spray. You get a rough figure by measuring the perimeter of the house and multiplying by the wall height, then subtracting the windows and doors that do not get body paint. A one story home has a single band of siding, so that math is straightforward: perimeter times one wall height.
The thirstier half of the equation is texture. This is where exterior differs sharply from interior. Smooth lap siding or primed, sealed stucco covers close to the ideal rate. But rough and porous surfaces fall off a cliff on the first coat: heavy-texture stucco, split-face block, rough sawn cedar, and bare brick can pull coverage down to 150 to 250 square feet per gallon, because the surface is full of pits and channels that swallow paint. Two one story homes with the same footprint can need very different gallon counts purely because one wears smooth siding and the other wears rough stucco. The coverage cornerstone behind all of this is our guide on how much a gallon of paint covers.
The coverage math
Exterior gallons come from the same formula as interior: siding area, divided by the coverage rate, multiplied by the number of coats. The coverage rate is where exterior gets its own rules. On smooth lap siding or primed stucco, a gallon of quality exterior paint covers roughly 300 to 350 square feet per coat. On rough or porous surfaces, that first coat can drop to 150 to 250 square feet per gallon as the pits and grain soak up paint. The second coat almost always goes further than the first, because the first coat has already filled and sealed the surface.
Coat count matters just as much. Most exteriors are two coats, especially over a color change or on weathered, chalky old paint. You can sometimes get away with one coat when you are going over sound, clean, same-color paint, but two coats is the safe planning assumption for durability outdoors. Our guide on how many coats of paint you need covers when one is genuinely enough. And bare wood or fresh masonry needs primer first, which is its own coat with its own coverage rate, so size it separately using our guide on how much primer you need. Trim, fascia, and doors are figured on their own too, since they use a different product and a different, slower application.
Gallons for a one story exterior
The table below splits the exterior into the buckets you actually buy paint for. The siding body is figured at two coats, and the trim, fascia, soffits, and doors are grouped as their own smaller bucket since they use trim-grade paint. These are typical planning ranges for two coats. Your real numbers depend heavily on siding texture and how much detail work the home carries.
| Surface (one story exterior) | Coats | Typical gallons |
|---|---|---|
| Siding body | 2 coats | 8 to 14 gallons |
| Trim, fascia, and soffits | 2 coats | 2 to 3 gallons |
| Doors | 2 coats | Under 1 gallon |
| Whole exterior total | 2 coats | 10 to 18 gallons |
Read the total as a band. A modest one story home with smooth lap siding lands near the bottom. A sprawling one story with rough stucco or split-face block, plus a lot of trim and fascia, pushes toward the top or beyond. For the next size up, and to see how a second band of siding changes the math, compare our sibling guide on how much paint for a two story house exterior. One useful thing about a single story is that the whole job stays within easy reach, so your measuring is simpler and your gallon estimate tends to be more reliable than on a taller home where the upper walls are harder to size by eye.
A worked example
Walk through a realistic one story home. Suppose the perimeter measures about 180 linear feet and the walls stand 9 feet tall to the eave. That gives a gross wall area of 180 times 9, or 1620 square feet. Subtract roughly 15 percent for windows and doors that do not get body paint, and you land near 1380 square feet of actual siding body.
For smooth lap siding at two coats and 325 square feet per gallon, that is 1380 divided by 325, times 2, or about 8.5 gallons of body paint. Now change one thing: make the siding rough stucco. On the first coat at 200 square feet per gallon and a second coat at 325, the same wall needs roughly 6.9 plus 4.2, about 11 gallons. Same house, same footprint, but the rough surface added more than two gallons on the body alone.
Add the trim, fascia, and soffits, which for a home this size run about 2 to 3 gallons across two coats, plus under a gallon for the doors. On the smooth version you land near 8.5 plus 2.5, about 11 gallons total. On the rough stucco version you land near 11 plus 3, about 14 gallons. Then add roughly 10 percent for touch-ups and round up to full cans, since you cannot buy part of a gallon.
It is worth pausing on how much that one texture change moved the number. The footprint, the perimeter, the wall height, and the coat count all stayed identical. The only thing that changed was the surface, and the body paint jumped from about 8.5 gallons to about 11. That is the practical reason you should never buy exterior paint off a floor-area rule of thumb. A rule of thumb cannot see whether your walls are smooth fiber cement or pitted stucco, and that single fact is often the difference between the low end and the high end of the range.
One more note on the doors and detail. A one story home may have a front door, a back door, and perhaps a side or garage entry door, plus shutters or a small porch ceiling. None of these individually needs much paint, but together they can absorb a gallon of trim-grade product, and they are slow, brush-heavy work. Count them as their own small line so they do not quietly get left out of your order and send you back to the store mid-job.
What changes how much you need
- Siding texture and porosity. This is the biggest driver on any exterior. Smooth lap siding covers at 300 to 350 square feet per gallon. Rough stucco, split-face block, rough cedar, and bare brick can drop the first coat to 150 to 250. Identify your surface before you count gallons.
- Siding type. Fiber cement, vinyl, wood lap, stucco, and masonry all behave differently. Masonry and rough wood are the thirstiest. Smooth, previously painted siding is the most economical.
- Color change and coats. Going over sound, same-color paint may allow a single coat, but a color change or weathered paint needs two. See how many coats you need before you assume one will do.
- Primer. Bare wood, fresh stucco, and raw masonry need primer first, which is its own coat. Our guide on how much primer you need helps you size it separately from the finish coats.
- Trim and detail. Homes with deep eaves, long fascia runs, shutters, and multiple doors carry more trim paint. The body number and the trim number move independently.
Turning gallons into a budget
Once you know the gallon count, the budget follows. Multiply gallons by your paint price per can, then remember that on most exterior jobs paint is only part of the total. Prep, from washing and scraping to caulking and priming, and the labor to reach every surface make up the larger share. Always buy about 10 percent extra so you have matching touch-up stock, and write down the exact product and color. To turn siding area and gallons into a real price, run the numbers through the painting cost calculator or start from a free painting estimate. For the full dollars breakdown of this exact job, see our companion guide on the cost to paint a one story house exterior, and our walkthrough on how to estimate exterior painting ties the gallons, the prep, and the price together.
Frequently asked questions
How many gallons of paint for a one story house exterior?
Most one story exteriors take about 10 to 18 gallons total for two coats, with roughly 8 to 14 gallons for the siding body and 2 to 4 for trim, fascia, and doors. That is a planning range. Rough or porous siding pushes it higher, so measure your actual walls and buy about 10 percent extra.
Why does siding texture matter so much for exterior paint?
Because rough and porous surfaces have pits and channels that swallow paint on the first coat. Smooth lap siding covers at about 300 to 350 square feet per gallon, but heavy stucco, split-face block, rough cedar, or bare brick can drop the first coat to 150 to 250. Texture, not floor area, is the biggest reason two similar homes need different gallon counts.
How do I estimate my siding area?
Measure the perimeter of the house and multiply by the wall height to get the gross wall area, then subtract roughly 10 to 15 percent for windows and doors that do not get body paint. A one story home has a single band of siding, so it is just perimeter times one wall height. That siding area, divided by the coverage rate and times the coats, sets your body gallons.
Do I really need two coats on the exterior?
Usually, yes. Two coats is the safe planning assumption outdoors for durability and even color, especially over a color change or weathered, chalky paint. You can sometimes use a single coat over sound, clean, same-color paint, but plan for two unless the surface clearly allows one.
Should I count primer in the gallon estimate?
Count it separately. Primer is its own coat with its own coverage rate, and you only need it where the surface demands it: bare wood, fresh stucco, raw masonry, or heavy stains. Sound, previously painted siding in good condition usually does not need a full prime. See our primer guide to size the amount.
How much extra exterior paint should I buy?
Buy about 10 percent more than the math says. It covers thin spots, an extra pass where the sun hits hardest, and leaves you matching touch-up stock for later repairs. Keep the leftover sealed and label it with the surface and product name so a future patch blends in.
Sizing the paint for a one story exterior comes down to measuring your real siding area, judging its texture honestly, doing the coverage math, and buying a little extra. When you are ready to price the job, run it through the painting cost calculator or start a free painting estimate, compare the dollars in our cost to paint a one story house exterior guide, and step up a size with how much paint for a two story house exterior.
