This post was updated on May 2, 2022

How Much Deck Stain Do I Need?
DeckStainHelp.com has become the Internet’s go-to site for wood surface staining tips. In this article, we offer insight to answer the conundrum of how much stain you should buy to complete a project. If you have questions on how to estimate the number of supplies to purchase for a project, feel free to leave us a comment with pictures.
How Much Deck Stain Should I Buy?
Before staining a deck you need to figure out the deck’s total square footage. Once this calculation is considered, you can figure out how many gallons of deck stain you need by reading the coverage rate of the stain you are buying. On average most deck stains cover 150-300 sq. ft. per gallon depending on the age, condition, and porosity of the wood.
How Much Deck Stain Do I Need?
- Measure Deck Floor: To figure out how much deck stain you should buy, start by measuring the deck floor. Take its width times length and write that number down. Besides the main deck floor, be sure to add in any smaller decking areas like a second-tier deck or stair landing platforms.
- Measure Deck Railings: Measure the linear feet of all the handrails including stair railings. Then determine the average height of the railing. This is usually around 3 feet on average. Multiply the total linear feet by the height in feet and write that number down next to the total number you got for the deck flooring.
- Measure Deck Steps: Determine how many steps you have total on your deck. After counting them up, measure how wide the steps are and then multiply these two numbers to come up with a total.
- Add Up Decking Area: Now take all three numbers from the deck flooring, railings, and stairs and add them together. That is the total square footage of your deck. Be sure to measure up and add in any extra areas of the deck that are less common. Add in any lattice, skirting, benches, pergolas, or other wood structures being stained.
Deck Stain Coverage
When measuring your deck it is best to use a tape measure or measuring wheel. If you do not have access to a measuring device you can come up with a close approximation by stepping the deck off. For example, to measure the floor stand on one end and with long strides walk to the opposite end counting each step.
A long step is close to a yard, which equals 3 feet. Multiply the number of steps you took by 3 and that is the total number of feet. Do this for all the steps mentioned above to calculate your deck’s total square footage.
Once you have a total square footage number you will then know how much deck stain you should buy to complete the project. Always buy a little extra if you can just so you do not run short. You can return any unopened cans to the store or just save them for the next time the deck needs to be refinished.
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As an article and comment contributor to the site, Scott has been around the pressure washing industry since attending college. In 1993 he started his first company called Oakland Pressure Wash specializing in exterior pressure washing and deck staining. That company evolved into OPW L.L.C. shortly thereafter concentrating more on exterior wood and deck restoration. Scott and his Deck Cleaning Michigan company have restored over 10,000 decks in the Metro Detroit area since the early years. He has become an authority in the deck restoration industry and has contributed to numerous wood restoration forums and informative sites.
All the products he suggests through this site are sold through online sites and in retail stores, allowing the consumer to choose their own means of purchase. Scott’s eCommerce sites do sell many top brands he endorses and if you appreciate any of the help he has offered then feel free to purchase from one of them.
How many gallons is stain will I need to cover 1100 square feet ?
That depends on the brand and type of stain you are using?
How many hours should it take to apply 1000’gallons of stain
There is no way to answer this question as it will vary drastically based on the stain type, stain brand, application method, and most importantly, user experience.
I asked your website twice how much does 1 gallon of Olympic stain semi transparent cover on a deck your website does not answer that
No, you never asked this question anywhere on our website. We checked and we would have answered if you had.
If I have a shed 10′ wide by 16′ deep by 14 ‘ tall with a aluminum roof. What amount of stain waterproof sealant would I need?
What is the total sq footage of all wood added up that is to be stained? Coverage also varies drastically based on the brand and type of stain being used so we will need to know that as well.
Is Olimpic maximum a good stain sealer?
No: https://www.deckstainhelp.com/olympic-maximum-stain-sealant-in-one-review/
I am in love with the deck at the very top of this web page. Was wondering what color that was so I could do my deck the same.
That is Restore A Deck Stain in Cedar color.
Will 5gal stain cover 18×16 deck floor
Coverage varies based on the stain brand, stain type, and how many coats are being applied so hard to say fer certain.
More than that your average stain will cover 450 to 600 ft.² but you will never get that answer from this website
No deck stain covers 450-600 sq feet per gallon. About half of that is average for 1 gallon.
16×20 deck and 3 stairs how much stain
Read the steps in the article above to add up and then check with the stain brand you are using to see the sq footage needed.
How many gallon 12×12
Depends on the brand, type of stain, and how many coats that need to be applied.
It’s Thomson water seat /Timber oil
Probably 1-2 gallons but not 100% sure as we do not use the Thompsons, it is a very poor product.https://www.deckstainhelp.com/thompsons-deck-stain-review/
I am staining a 8by8 porch how much stain do I need
Depends on the brand and type of stain.
How many gallons does it take to seal 384 square feet with Penofin oil Ipe wood
For IPE wood? About 2 gallons.
I live on a lake in Indiana, so the walkway, deck and pier are exposed to intense heat and cold. It is a 11 years old and comprised of pressure treated pine. I have power washed the deck and restained every 3 years. The boards are now starting to cup. In the shaded areas they have mold and mildew. The total square footage is approximately 2,000 sq feet. What product do you recommend, how much should I buy, and best method of application?
Thank you
Dean
Try the Armstrong Clark stains or TWP 1500. Coverage varies but about 15-20 gallons for the two coats. Apply with stain pads and brushes.
We are refinishing an older wood deck. It is now powerwashed, drying. There are some open holes….where there were knots that have fallen out. Do those need to be FILLED prior to applying stain? If so, what product and how to do it….thanks
No, and wood filler does not work on exterior wood. Just leave as is.
Best way to apply semi solid oil stain on old deck
Best “dark chocolate ” color stain that will last the longest.
Try TWP 1504 Dark Oak or Armstrong Clark Black Walnut.
I have a 20x 20 deck railings the same 4 steps 4×6 how much sealer would i need?
Please read the above on how to measure all and then add up. The next step would be to determine what stain you are using, how many coats needed, etc.
Just had 500 sq. Deck installed with rails and 3 sets of steps. What’s the best dealer and best way to apply it
I meant sealer, not dealer. Thank you
See here about new wood: https://www.deckstainhelp.com/staining-a-new-deck/
After I stain my new treated pine deck will it take the same amount of stain for the second coat or less. How do I figure how much for the second coat?
About the same amount.
How many gallons of stain I need to cover a 9×11, 99 square foot deck for 2 coats and one coat underneath?
It depends on the brand and type of stain as coverage varies.
I have a new redwood landing and stairs. About 50 square feet. How much sealer do I need to buy?
Depends on the brand but 1 gallon should cover it.
How much deck stain does it take for 375 square ft
Depends on the brand and type of stain you are using?
I HAVE 27′ x 40′ deck and need to know how much Thompson clear water seal will it take?
Thompsons is a useless product: https://www.deckstainhelp.com/thompsons-waterseal-finish-review/
As for how much is needed. About 10-15 gallons if you decide to use it.
lol what brand do you recommend?
All clear sealers will not provide UV protection from graying. Best to use a penetrating semi-transparent stain like one of these: https://www.deckstainhelp.com/the-5-best-deck-stain-reviews-and-ratings/
How much Stain to cover 50 square metres ?
Depends on the brand and type of stain being used?
if i am staining a wardrobe 15 x 40 how much stain do i need
I do not understand your question. Coverage also varies on the stain brand and type you are using.
Does the above article generate to the amount of stain one needs for one coat?
One coat.
I am re-staining a deck that was done about 4 years ago. It has held up pretty well but will need a good cleaning and light sanding in spots. It is unclear whether on-line calculators used to estimate how much stain to buy assume that the deck has never been stained before or that the deck was stained previously. Would it be correct to assume that if I am using the same product/color in a semi-transparent (water based) that I would not need as much stain? The deck is about 540 sq ft. Thanks!
No. You will need the same amount as previously.
Thanks for the quick response!
You are welcome!
I’m in the Greater Seattle area and need and I’m looking for someone to stain, seal and waterproof my deck and soffits. I had a contractors come out and give me a bid, but I’m wondering if there’s a special way to measure the square footage as the numbers he gave me seem to be way over. I have rails, spindles, steps, soffits and lattice. I’ve measured the soffits and my numbers are significantly less than the contractor’s and my measurement is an over estimate that includes areas where the wood is cutout to for other structures. Their measurement was 375 sqft while mine was 343 sqft.
I would trust the contrator to measure correctly and it only a 32 difference in feet.
As a contractor myself I never give an estimate in which the number doesnt end in either zero or 5. If a contractor gave you a number like yours, 343 then they usually will end up needing more. Always round up. Here is why, you have waste in materials. You also have the fact that we havent been able to test to see how your wood will soak up the product. Many factors. Also, 32 square feet isnt a huge number. If he was 500 or 1000 square foot off then you would second guess it.
We bought a house with a deck of 350 square feet. The wood is very porous since it should have been done quite awhile ago. We power washed it and now want to apply ‘Woodsman’ premium ‘solid’ stain. How much should we buy?
Sorry but not familiar with that brand and coverage varies by the brand.
I would guess 2-4 gallons.
We just installed a new 14×16 redwood floating deck. this last week. No railings. How much stain do I need.
Hello, this varies drastically on the brand and type of stain you will be using. See this article on new wood: https://www.deckstainhelp.com/staining-a-new-deck/
My back yard deck is clear wood about 4 month old and it is 325 SQ feet , how much do I need to buy to stain it . and it is new do I need to clean it first
Yes prep with the Restore A Deck Cleaner kits. As for the stain needed, it varies on the brand you choose. Do you know which one you will be using?
No I do not know what brand I am going to use , I was looking to buy a big 5 gallon maybe . Thompson brand I think , or I would like to go Sherman Williams , it is 27 feet long nd 1feet wide ,
Roughly 3000 sq ft for a multiple level deck, railings, steps, lattice etc…..how much AC semitransparent stain for 2 coats? Decks was stained with same AC 3 Years ago
Do you remember how much you used last time? Should be about the same. AC spreads well but this is a big deck. Most likely you will need 15-20 gallons.
So I'm restaining my deck. I've striped and sanded the entire deck. Total sq ft is 555 sq ft. How many gallons of stain will I need?
Depends on the stain brand as they do not all coverage the same sq. footage. Have you choosen one yet?
How do I figure square footage of deck steps
Width of steps x the tread/riser combined. For the railings we multiply the height times the length.