The short answer
The two crews were not pricing the same job. One measured the deck floor. We measured every surface that gets stain, which came to 595 square feet, and the floor was only 192 of it. The rest was two stair sets, 28 feet of railing, and killing the black mold growing on the rail caps.
If you want a number for your own deck instead of reading ours, that takes about two minutes.
A Bellingham homeowner called us in late July about restaining a deck. Colton went out, tape measured it, took photos, and we sent a bid for $4,250 with tax included. They also had a local handyman look at it, and that number came back around $1,000 on the same deck in the same week, about three thousand dollars under ours.
They thought our number was too high. With only those two figures in front of you, that is the reasonable thing to think, and we did not do a good enough job explaining the gap at the time.
So we are publishing the bid instead. What follows is the real estimate with the name and address stripped out, the actual photos from the walkthrough, and the arithmetic under both prices. It is the most useful thing we can hand the next person who gets two quotes and no explanation.
The floor is a third of your deck
Every cost calculator online prices a deck by its floor. Length times width, dollars per square foot, done. Our own Bellingham deck staining cost guide quotes $3.30 to $6.60 per square foot the same way, because that is the number homeowners are looking for.
Here is the problem with it. A deck is not a floor. This one had a floor 12 feet by 16 feet, which is 192 square feet. It also had a main stair, a second stair by the door, and 28 linear feet of railing with balusters and a 13 inch cap. Both faces of that railing take stain. So does the top of the cap, and so does the underside.
Measure every surface that actually gets coated and this deck comes out at 595 square feet. That is three times the floor.
None of that is us padding a number, it is just what is on the deck. Which makes it the first question worth asking anyone who bids yours: how many square feet are you pricing, and does that include the railings and the stairs? Two crews who answer that differently will never land near each other, and neither one has to be lying to you.
Railings are the slow part
Rolling an open deck floor is fast work. A hundred square feet goes by in minutes. Railings are the opposite. Every baluster has four faces and two tight corners where it meets the rail, and every one of those corners gets brushed by hand. You cannot spray your way out of it on a deck surrounded by ferns and planting beds.
On this deck the railings and the stair rails together came to 289 square feet, which is more surface than the floor and both stair sets combined.
We measured the main railing at 7.0 square feet per linear foot. If you want to check that math: both faces of a 3 foot balustrade is 6 square feet per foot, and the top and underside of a 13 inch cap adds another 2.17, so the honest geometric number is 8.17. We charged for 7, which means the bid under-measured its own railing by about 14 percent.
What we found on the railings
This is the part that moved the price, and it is the part a quick look misses. There was black mold growing on the underside of the rail caps and running down the balusters on the shaded side, along the length of the run rather than in one patch.
Sherwin-Williams and Benjamin Moore both say in writing that mildew has to be removed before their products go on. That is not a suggestion in the fine print, it is the condition of the product warranty. Coat over growth and the new film bonds to the mold instead of the wood, and a finish that should give you four or five years starts letting go inside the first wet season.
The part that costs real money is what happens after that. Once mold is sealed under a solid stain you cannot wash it out. The deck has to be stripped back to bare wood before anyone can start over, and stripping is a bigger job than the prep that got skipped.
So we priced it out properly. A sodium percarbonate cleaner that soaks, gets scrubbed in by hand along the grain, and kills what is growing. Then an oxalic brightener that lifts the staining and the rust marks around the old screws. We do not use household bleach on decks. It breaks down the wood fibers, leaves spores alive, and corrodes the same fasteners that were already bleeding rust into the boards.
The walkthrough turned up five other things worth naming, all of them in the bid:
- The finish had failed on the rail caps, so those get scraped and sanded back to sound wood.
- One 2x4 was past saving.
- Several screws were proud and corroded, and those get set flush before anything is coated.
- Two planter boxes had been sitting on the rail cap holding water against it for years. We put it in writing that we would not know what the wood under them looked like until they came off, with a written change order and a cap on the cost if it turned out badly.
- The ferns and planting beds against the posts all need covering before any washing starts.
Want this level of detail on your own deck?
Get my free quoteThe bid she actually got
Here is the estimate as it went out, with her name and address removed and the signature block taken off. Everything else is what she saw.
bellinghampaintpros.com
Licensed & insured · WA
Site notes
Colton tape measured the deck on July 28. The floor is 12 feet by 16 feet, the main stair is 7 feet by 5.5 feet, and the railing runs 28 linear feet at 3 feet high with a 13 inch cap on top. The price below is built on those numbers.
This deck is at the restoration stage, not the recoat stage. The finish on the floor has worn through in the traffic areas and the boards have silvered unevenly. There is black mold on the underside of the rail caps and down the balusters, and one 2x4 needs replacing. So the work is in the prep: a sodium percarbonate mold treatment with dwell time and hand agitation, an oxalic brightener, full sanding of the stair treads, the rail caps scraped and sanded back to sound wood, and the board replaced. Then two coats of solid color stain.
Two notes from the walkthrough. The planter boxes have held water against the rail cap for a long time, and we will not know what the wood under them looks like until they come off. And to answer the question you asked: no, the whole deck does not need sanding. The treads and the caps do, because the finish there has failed. Everything else gets washed, treated, and scuff sanded, which is all a solid stain needs to bond.
Your price
Both options are the same crew, the same prep, and the same workmanship. Premium steps up to a stain that holds color longer in the sun and carries a longer manufacturer warranty. Prices include all labor, materials, the mold treatment, the board replacement, setup, and Washington state sales tax.
Scope of work
| Surface | Qty | Prep | Coats |
|---|---|---|---|
| Deck floor, 12 ft by 16 ft | 192 sq ft | Wash, mold treatment, brighten, scuff sand | 2 |
| Main stair, 7 ft by 5.5 ft · treads, tread edges, and stringers | 64 sq ft | Wash, full sand | 2 |
| Second stair by the door · treads, stringers, and rail | 50 sq ft | Wash, full sand | 2 |
| Deck railing, 28 lin ft at 3 ft high · both faces, plus the 13 in cap top and underside | 196 sq ft | Mold treatment, scrape and sand cap, sand balusters | 2 |
| Main stair railings, both sides · both faces | 93 sq ft | Wash, scuff sand | 2 |
| Mold treatment on rail cap undersides and balusters | As found | Included | n/a |
| Replace one 2x4 | 1 board | Included | 2 |
| Proud and corroded fasteners set before coating | As found | Included | n/a |
| Planter boxes lifted off the rail cap and replaced | 2 boxes | Included | n/a |
| Iron staining around corroded screws lifted with brightener | As found | Included | n/a |
| String lights and light pole taken down and re-hung, at no charge | 1 run | Included | n/a |
| Total coated surface | 595 sq ft |
Deck railing area is calculated at 7.0 square feet per linear foot across 28 linear feet, counting both faces of the balustrade, the top and underside of the 13 inch cap, and the posts. Stair railings are calculated at 5.2 square feet per linear foot across 18 linear feet. We wash at low pressure only; high pressure drives water into the boards and raises more grain than it removes. Coat counts are minimums, and BPC may apply additional coats at no charge to reach manufacturer-spec coverage. Estimated duration is three working days of dry weather: wash and mold treatment, then dry-down and prep, then both coats.
Payment schedule
Nothing is charged before you sign. Substantial completion means all surfaces in their final coat, punch list issued, site cleaned, and BPC equipment removed. Final payment is due within 7 days of substantial completion.
Not included
- Replacement of any board beyond the one 2x4 listed above. If prep uncovers soft or rotted wood we stop and photograph it, then send a written change order at $90 per hour plus materials at cost, with a not-to-exceed amount. No additional repair begins without your written approval.
- Structural repair, re-fastening, or leveling of the deck framing, joists, or stair stringers beyond setting surface fasteners.
- The underside of the deck, the support posts and framing below the deck line, and the fence. Worth saying plainly: your deck stands about four feet off grade and those posts and the rim joist are visible from the yard. They keep their current color unless you add them. We are glad to price the posts and skirt as an option.
- Moss or mildew remediation on adjacent surfaces such as the roof, siding, or walkway. The mold treatment in this price covers the deck and railings only.
- Replacing rusted fasteners. Solid stain will hide the existing iron staining, but a badly corroded screw can eventually bleed through any finish. Replacement is quoted separately if you want it solved for good.
- Lead paint abatement. This home may predate 1978. We are EPA RRP certified and that work is quoted separately if it applies.
Important terms
- Quantities. The square footage and railing length shown were tape measured on site on July 28, 2026. The second stair by the door was estimated from photographs and is confirmed by tape on the first morning. If it measures materially larger or smaller, we adjust the price with you in writing before any work starts, and you are free to walk away at that point.
- Solid stain. Solid color stain is a film finish. Returning to a translucent finish later requires stripping the deck back to bare wood.
- Mold. The treatment kills what is growing and lifts the staining. Wood that has been colonized for a long time can hold a shadow in the grain after treatment, which a solid stain covers. We are not able to warrant that mold will not return on a shaded deck under trees.
- Warranty. The stain manufacturer carries its own product warranty on the coatings used, two to five years depending on the line selected. A properly maintained deck finish in our climate typically wears two to four years before a maintenance recoat.
- Credentials. WA L&I licensed, general liability and workers' comp insured, EPA Lead-Safe certified for pre-1978 homes.
The estimate as sent, July 28, 2026. The name, address, project number and signature block are removed, the direct phone is replaced with our main line, and some boilerplate is trimmed for length here. Prices, quantities and the scope table are exactly as they went out.
Divide the $4,250 by the 595 square feet it covers and you get $7.14 a foot with the tax in it, or $6.57 before tax, which lands inside the range in our own cost guide. Divide the same bid by the 192 foot floor and you get $20 a foot, which sounds outrageous even though it is the same job and the same money measured against a different denominator.
What $1,000 actually buys
We want to be careful here, because $1,000 is real money for real work and we are not calling anybody a crook. On a deck in decent shape, $1,000 is a fine price for a careful wash and a coat or two on the floor. If that is what your deck needs, pay it and skip the rest of this section.
What it cannot cover is a restoration of this size. Run the numbers on the stain alone. Sherwin-Williams rates SuperDeck Solid at 200 to 400 square feet a gallon and notes that weathered wood drinks more than new. Freshly sanded gray cedar is at the thirsty end. First coat on 595 feet takes right around three gallons, second coat takes a bit over two, so you are buying six. That is about $348 at retail before anybody opens a sheet of sandpaper.
Add the mold cleaner and the brightener, the abrasives for 595 square feet including all those balusters, the replacement board, and the plastic and tape to cover the ferns, and materials land near $605. Take the tax out of $1,000 and you have about $919 to work with. That leaves roughly $314 for every hour of labor on the job.
Three days of the work in this scope is 36 to 48 crew hours. At Whatcom County rates, $314 buys six to nine. So a $1,000 bid on this deck is not a discount on our scope. It is a different scope, and the part that comes out is the prep, because prep is invisible on the day the crew leaves and obvious a year later.
Five questions that sort any deck bid
Ask these of everybody who bids your deck, us included. The gap between two prices usually shows itself by question three.
- How many square feet are you pricing, and does that count the railings, both faces, and the stairs?
- What happens to the mold before the stain goes on? If the answer is a pressure washer and nothing else, the growth is still alive.
- Which surfaces get sanded and which just get washed? A good bidder will tell you the whole deck does not need sanding, and will say which parts do.
- Is the number in writing, with tax, with the exclusions listed? A bid that has no "not included" section has not been thought through.
- Are you registered with Washington L&I? You can check any contractor free at lni.wa.gov and it takes about a minute. Registration means a bond you can actually claim against if the finish fails.
What they decided
They went with the lower quote. That is a completely defensible call. Not every homeowner has four thousand dollars for a deck in July, and a floor recoat now beats nothing at all for three more years while you save for the full job.
What we would say to anyone in that spot is the one thing about this that is hard to undo. Stain that goes over live mold seals it in, and the next crew has to strip the deck before they can fix it.
If the budget only reaches a recoat, the money goes further treating the growth and coating less of the deck than it does coating all of the deck over the growth. That is a real option and almost nobody gets offered it.
What we charge for deck work
So you have our numbers before you call. A floor-only wash and recoat in Bellingham generally lands between $400 and $1,000 depending on size and condition. A full restoration, meaning stairs, railings on both faces, sanding where the finish has failed, mold treatment, and two coats of solid stain, typically runs $3,500 to $5,500. The deck in this post priced at $4,250 with tax in it.
Sometimes the walkthrough tells us a deck only needs the small job. We say so, quote the small number, and you can hire us or anybody to do it. We would rather be the company you call in three years than the one that oversold you now.
If you are collecting deck quotes this summer, have us out. The walkthrough is free, Colton brings a tape measure, and the bid comes back itemized by surface like the one above so you can lay it next to anyone else's and compare line by line.
Two more things worth reading before you book. Our Bellingham deck staining cost guide covers the standard price bands by deck size, and if you are trying to work out whether your deck is worth restoring at all, deck restoration versus replacement walks through when the framing has gone too far. If the growth on your railings looks like the photos above, moss and mildew prep explains what we do about it and why.