Flooring
Hardwood floor refinishing cost
Refinishing runs about $5.40 a square foot, against a screen and recoat at about a third of that. But the first question is not price: sanding spends wood, and a floor only has what sits above the tongue. This works out how much is left before it works out what it costs.
Written and edited by Pablo Ruiz Quintero
Last reviewed 2026-09-16 · Nothing you type leaves your browser
What is the floor?
The first question is not what it costs. It is whether the floor has the thickness to take it.
The whole floor, including under furniture that moves out.
The classic strip floor. A quarter of an inch of wood above the tongue, which is a great deal of life if nobody wastes it.
Look at a threshold or a vent: if the nail heads or the tongue are visible, it has had more than you think.
Grey or black patches, water stains, or scratches you can catch a fingernail in mean the wear is in the wood. Dullness, fine scuffs and traffic lanes that still have colour under them are finish, and a recoat fixes those without removing anything.
Dries in hours, barely smells, and stays the colour it went on. Three coats in a day is realistic, which is why most floors are done this way now.
Used only to pick a regional labour rate. It stays in your browser.
Sandings left
7
0.219 in of wood left above the tongue · each full sand takes 0.031 in
A full sand is the right call here
The damage is in the wood and the floor has 7 sandings left, so a full sand is both necessary and affordable in the only currency that matters here — thickness.
Full sand against a recoat
The same floor, and the difference is not only money.
| Full sand | Screen and recoat | |
|---|---|---|
| Cost | $3,241 | $1,140 |
| Per ft² | $5.40 | $1.90 |
| Days out of use | 2 | 1 |
| Wood removed | 0.031 in | None |
| Fixes damage in the wood | Yes | No |
Shopping list
- Drum sander belts
Three passes at 36–40, 60, 80–100 over 600 ft²8 belts - Edger discs
The perimeter and anywhere the drum cannot reach. This is where most of the abrasive goes.22 discs - Buffer screens
Blending the edger work into the field before finishing2 screens - Waterborne polyurethane, 3 coats
500 ft² a gallon a coat · 3 h between coats4 gallons
The floor is unusable for 2 days
Which is the real cost of refinishing, and the reason it is done before moving in.
- Sanding1 day, and the dust goes everywhere the plastic does not
- Finish3 coats, 3 h apart
- Walk on itAfter about a day
- Furniture back2 days — and lift it, do not slide it
- Rugs14 days. A rug on uncured finish leaves its outline permanently.
What it costs
National average. Sanding, finishing, abrasives and materials. Furniture moving is usually extra.
$5.40 per ft². Doing the whole floor at once is far better value than one room, because moving the machines in costs the same either way. Replacing it instead is the comparison worth making if the floor is close to its last sanding.
Worth knowing
- Every full sand takes about 0.031 in off the floor, and a floor only has what sits above the tongue. Solid, 3/4 in starts with 0.25 in (6.4 mm); yours has 0.219 in left after 1 previous sanding. That is the budget, it does not refill, and it is the reason to ask whether a recoat would do.
- The grit sequence is not optional: 36–40 then 60 then 80–100. Every skipped grade shows through the finish as scratch the light picks up, and it cannot be fixed by the next coat — only by sanding back and starting again, which costs another 0.031 in of floor.
- 3 coats of waterborne polyurethane, 3 hours between them. Walk on it after a day, furniture back after 2, and no rugs for 14 days — a rug laid on uncured finish leaves its outline permanently.
On this page — 8 sections
- 01A floor has a thickness budget, and it does not refill
- 02Finding out what you actually have
- 03What refinishing hardwood floors costs, against the recoat nobody offers
- 04Three passes, and why none of them is optional
- 05What goes on top, and how long it takes
- 06Five ways this goes wrong
- 07How the calculator works it out
- 08The words on a floor finisher's quote
A floor has a thickness budget, and it does not refill
The short version
- Sanding spends wood. About 0.031 in a pass, out of the 0.25 in a solid floor has above the tongue.
- Engineered is decided by the wear layer. Under 2 mm, a drum sander goes through it in one pass.
- Most floors want a recoat, not a sand. A third of the price, one day, and no wood removed.
- The grit sequence is not optional. A skipped grade is invisible on bare wood and unmistakable under finish.
Every article about refinishing opens with a price per square foot. It is the wrong first question, because refinishing is not something a floor can have indefinitely — it is something it can have a fixed number of times, and each one is spent permanently.
A solid strip floor is three quarters of an inch thick, but only the part above the tongue can be sanded: about a quarter of an inch. Below that the tongue is exposed, boards begin to break free at the edges, and there is no repair short of replacement.
sandings left = (usable thickness − previous × 1/32) ÷ 1/32
- usable thickness
- 0.25 in on a solid 3/4 in floor; the wear layer on engineered
- 1/32 in
- what a full three-pass sand takes off — about 0.8 mm
- previous
- sandings the floor has already had, which is usually more than the owner thinks
Worked through — A solid floor sanded twice already: 0.25 − 2 × 0.031 = 0.188 in left, which is 6 more full sands. That is a ceiling, not a plan: nail heads, cupping and a first pass over an uneven floor all take more than the nominal, so a solid floor gets four to six in a lifetime rather than the eight its thickness allows. The same discount applies to engineered, where the arithmetic gives a 2 mm wear layer 2 and anyone sensible treats it as one.
National Wood Flooring Association, NWFA Installation Guidelines · checked 2026-09-16
Finding out what you actually have
Almost nobody knows what their floor is made of, and the answer changes everything. A solid floor and a 2 mm engineered floor look identical from above and have completely different futures.
The place to look is an edge. Lift a floor vent, look at a threshold strip, or check where the floor meets a step — anywhere the side of a board is visible. On solid timber the grain runs continuously through the thickness. On engineered you can see the line where the veneer stops and the plywood begins, and that line is what you are measuring.
| Floor | Usable | Sandings | Notes |
|---|---|---|---|
| Solid, 3/4 in | 6.4 mm | 8 | The classic strip floor. A quarter of an inch of wood above the tongue, which is a great deal of life if nobody wastes it. |
| Solid, 5/16 in thin strip | 2.3 mm | 2 | Thin solid, glued down. It looks like a full solid floor from above and has a fraction of the depth — treat it like engineered. |
| Engineered, 6 mm wear layer | 6 mm | 7 | The thickest engineered made, and the only one that genuinely rivals solid for sandings. |
| Engineered, 4 mm wear layer | 4 mm | 5 | Good engineered. Two full sandings in its life, maybe three if they are light and done by someone careful. |
| Engineered, 2 mm wear layer | 2 mm | 2 | The practical floor for machine sanding. One pass, once, and only by someone who has done it before. |
| Engineered, under 2 mm | 1 mm | None | A veneer. A drum sander goes through it in one pass and there is no repair — this floor gets screened and recoated, or replaced. |
Sandings from new, and every one of these is an arithmetic ceiling. In practice a solid floor gets four to six rather than eight, and a thin wear layer gets one rather than two — nail heads, cupping and the first pass over an uneven floor all take more than the nominal.
What refinishing hardwood floors costs, against the recoat nobody offers
Abrading the existing finish and putting a new coat on top. It removes no wood at all, so it costs a floor nothing from its life, and it is the right answer whenever the wear is in the finish rather than in the timber. The test is simple: if there are grey or black patches, water stains or deep scratches you can catch a fingernail in, the wear has reached the wood and this will not fix it.
It takes a day. It costs about a third of a full sand. It removes no wood at all, so the floor keeps every sanding it has left for when it genuinely needs one. And for a great many of the floors that get sanded every year, it is what was actually needed.
The test takes ten seconds and needs nothing but daylight and a fingernail.
| Recoat will fix it | Only sanding will | |
|---|---|---|
| How it looks | Dull, scuffed, traffic lanes with colour still under them | Grey or black patches, bare wood showing |
| Scratches | Fine, in the finish, catch nothing | A fingernail catches in them |
| Water marks | None | Dark rings or a raised grain |
| Pet stains | None | Black, and they may not sand out either |
| Cost | About a third | The full figure |
| Days out of use | One | Two to five, depending on the finish |
| Wood removed | None | 0.031 in of a finite budget |
Three passes, and why none of them is optional
Sanding a floor is not one operation. It is a sequence, and every step exists to undo the damage of the one before it.
| Grit | Job | What happens if it is skipped |
|---|---|---|
| 36–40 | Cut | Takes off the old finish and levels the boards. This is the pass that removes the wood. |
| 60 | Remove the scratch | Erases the marks the cutting pass left. Skipping it means seeing them through the finish. |
| 80–100 | Refine | The surface the finish actually sits on. Finer than this and the finish struggles to key. |
Things that show up later
- Nail heads punched below the surface before the first pass, or they tear the belt and mark the floor.
- The drum never stationary. Two seconds in one place is a dish that shows under low light forever.
- Edger work blended into the field with a buffer, or the room reads as a border and a middle.
- Every grade taken over the whole floor, edges included, before moving up.
- Vacuumed and tacked between coats — a single hair in the second coat is under the third one too.
- Finish applied along the boards, wet edge kept, and nobody walking back across it.
- Plastic on the doorways. Sanding dust reaches rooms you did not open.
What goes on top, and how long it takes
| Finish | Coats | Between | Furniture | Rugs |
|---|---|---|---|---|
| Waterborne polyurethane | 3 | 3 h | 2 d | 14 d |
| Oil-modified polyurethane | 3 | 24 h | 4 d | 30 d |
| Hardwax oil | 2 | 12 h | 2 d | 14 d |
The last column is the one that surprises people. Finish is dry in hours and cured in weeks, and those are different things. A rug laid on a floor that is dry but not cured leaves its outline in the surface — not a mark on top of the finish, a mark in it — and the only remedy is sanding the floor again.
0.031"
Removed per sand
0.8 mm
6.4 mm
A solid floor's budget
above the tongue
~⅓
Cost of a recoat
against a full sand
14–30 d
Before rugs
dry is not cured
If the floor is out of sandings, the comparison is against a new one. The flooring calculator gives boxes, underlay, trim and the cost of lifting what is there.
Replacing it instead?Five ways this goes wrong
01Sanding a floor that needed a recoat
It costs roughly three times as much, takes days instead of one, and spends 0.031 in of a budget that never refills.
Instead — Check whether the wear has reached the wood. Grey patches and fingernail-catching scratches say yes; dullness and scuffs say no.
02Machine sanding a thin engineered floor
A drum sander goes through a 1 mm veneer in a single pass, and there is no repair. The floor is finished, in both senses.
Instead — Measure the wear layer at a vent before anyone starts. Under 2 mm means recoat or replace.
03Skipping a grit to save time
The coarse scratch stays in the wood. It is invisible on bare timber and obvious the moment finish goes on and light rakes across it.
Instead — Every grade over the whole floor, edges included: 36–40, then 60, then 80–100.
04Putting rugs down when the floor feels dry
Dry and cured are weeks apart. A rug on uncured finish leaves its outline permanently, and the only fix is sanding again.
Instead — Two to four weeks, depending on the finish. It is on the tin and almost nobody reads it.
05Doing one room at a time
Machine hire, setup and drying days cost the same for 120 ft² as for 600, so most finishers charge a minimum either way — and the boundary between an old finish and a new one always shows at the doorway.
Instead — Do the whole connected floor in one go. It is much better value and it is the only way the colour matches.
How the calculator works it out
- 01Find out what the floor isSolid, or engineered with a wear layer. At a vent or a threshold you can usually see the edge of a board and measure it.
- 02Count the sandings it has hadVisible nail heads, a thin-looking board edge or a tongue showing anywhere mean it has had more than the owner thinks.
- 03Work out what is leftUsable thickness minus 0.031 in for each previous sanding, divided by 0.031 again.
- 04Decide whether the wear is in the finish or the woodGrey patches, water stains and deep scratches are wood. Dullness and scuffs are finish, and a recoat fixes those.
- 05Count the abrasive and the finishThree passes of belts and discs over the area, then coats at the finish's spread rate.
- 06Plan the days, not just the moneyThe floor is unusable while it is done, and rugs stay off for weeks after that.
Usable thickness above the tongue, the depth a pass removes and the grit sequence follow the wood flooring association’s guidance. Finish coverage and coat counts come from manufacturer data sheets; abrasive consumption and labour from a survey of floor finishers. Everything is on the sources page, dated.
Two assumptions worth stating. The sandings figure is the arithmetic ceiling — solid floors get four to six in practice rather than the eight the thickness allows, because nail heads, cupping and the first pass over an uneven floor all take more than the nominal. And the recoat comparison assumes the wear genuinely has not reached the wood: if it has, a recoat is not a cheaper version of the same job, it is a different and ineffective one.
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The words on a floor finisher's quote
Wear layer and screen-and-recoat are the two worth knowing before anyone quotes. One decides what is possible; the other decides what is necessary.
- Wear layer
- The thickness of real wood above the tongue — on solid flooring the part above the groove, on engineered the veneer over the plywood core. It is the only budget a floor has for sanding, and it does not refill.
- Screen and recoat
- Abrading the existing finish with a buffer and putting a fresh coat on top. It removes no wood, takes a day, and costs about a third of a full sand.
- Drum sander
- The machine that does the field of the floor. It removes wood fast, and leaving it stationary for two seconds cuts a dish that shows for the life of the floor.
- Edger
- A hand-held disc sander for the perimeter and anywhere the drum cannot reach. It is where most of the abrasive goes and where most amateur jobs are given away.
- Grit sequence
- The order of abrasives: 36–40, then 60, then 80–100. Each grade removes the scratch the previous one left, and a skipped grade shows through the finish.
- Cut pass
- The first, coarsest pass. It takes off the old finish and levels the boards, and it is the pass that actually consumes the floor's thickness.
- Waterborne finish
- Polyurethane carried in water. It dries in hours, barely smells and stays the colour it went on — which is why most floors are finished with it now.
- Oil-modified polyurethane
- The traditional solvent finish. It ambers over time, which on oak is the warm look people mean by an old floor, and it needs a day between coats.
- Hardwax oil
- A penetrating finish rather than a film. A worn patch can be spot-repaired instead of needing the whole floor redone, at the cost of maintenance oiling every few years.
- Cure
- The weeks after the finish is dry, while it reaches full hardness. Walking is fine long before curing is done; rugs are not, because a rug on uncured finish leaves its outline permanently.
- Dish and chatter
- Two drum sander faults: a dish is a hollow from pausing in one place, chatter is a washboard ripple from a worn drum or a bad belt. Both are visible under low light forever.
- Buffer
- A rotary machine used with a screen to blend the edger work into the field and to abrade between coats. It is what makes a floor look like one floor rather than a middle and a border.
Common questions
- How many times can a hardwood floor be refinished?
- A solid 3/4 in floor has about 0.25 in (6.4 mm) of wood above the tongue and each full sand takes roughly 0.031 in, so 8 in theory and four to six in practice once nail heads and unevenness are allowed for. Engineered depends entirely on its wear layer: 2 mm works out to 2 on paper and should be treated as one careful sanding, and under 2 mm is none at all.
- Can engineered wood floors be refinished?
- Only if the wear layer is thick enough, and the honest number is lower than the arithmetic. A 6 mm layer divides into 7 passes on paper and should be treated as two or three, because the one thing that cannot happen is breaking through the veneer. At 2 mm, once, by someone who has done it before. Under 2 mm, none: a drum sander goes through it in a single pass and there is no repair. Measuring it matters more than any other question on this page, and it is usually visible at a floor vent.
- How much does it cost to refinish hardwood floors?
- Typically $3 to $7 per square foot for sanding and three coats, with staining adding roughly a dollar. Most finishers have a minimum of around $600 because moving the machines in, hiring them and the drying days cost the same in a small room as a large one — which is why doing one room alone is poor value.
- What is screen and recoat?
- Abrading the existing finish and putting a new coat on top. It removes no wood at all, so it costs a floor nothing from its life, and it is the right answer whenever the wear is in the finish rather than in the timber. The test is simple: if there are grey or black patches, water stains or deep scratches you can catch a fingernail in, the wear has reached the wood and this will not fix it.
- Should I sand or just recoat?
- Look at what is worn. If the finish is dull and scuffed but the wood underneath still has its colour, recoat — one day, a third of the price, and the floor keeps every sanding it has left. If there are grey or black patches, water marks or scratches you can catch a fingernail in, the damage is in the timber and only sanding reaches it.
- How much does sanding remove from a floor?
- About 0.031 of an inch for a full three-pass sand — roughly 0.8 mm. It sounds like nothing until you count: five sandings is an eighth of an inch, and a floor only has a quarter of an inch to spend.
- Why can't you skip grits when sanding a floor?
- Each grade removes the scratch pattern the previous one left. Going from 36–40 straight to 80–100 leaves the coarse scratch in the wood, invisible on bare timber and unmistakable once the finish goes on and the light rakes across it. The only fix is sanding back and starting again, which costs another pass of the floor's thickness.
- How long before I can walk on a refinished floor?
- About a day with waterborne finish and longer with oil-modified. Furniture goes back after two to four days, lifted rather than slid. Rugs stay off for two to four weeks — a rug laid on finish that has not cured leaves its outline in the surface permanently, and that one is not repairable without sanding again.
- Can I refinish floors myself?
- The machines hire by the day and the process is not complicated, but a drum sander is unforgiving: pause for two seconds and it cuts a dish that shows under low light for the life of the floor. Blending the edger work into the field is the part most people find hardest. If it is a first attempt, start in a cupboard and work outwards.
- Waterborne or oil-based polyurethane?
- Waterborne dries in hours, barely smells and keeps the wood the colour it is — three coats in a day is realistic. Oil-modified ambers over time, which on oak is the warm traditional look, and it needs a day between coats with the smell through the house. Neither is more durable than the other in any way that matters at home.
- Do I need to stain, or just finish?
- Stain only if you want a different colour from the wood. It adds a day, it is the step that cannot be rushed, and on a floor with any patching it is unforgiving — new wood takes stain differently from old. Natural with a clear finish is the safer choice on a repaired floor.
- Is refinishing cheaper than replacing?
- Usually by a long way — a third to a half of a new floor, with no removal and no disposal. The exception is a floor with no sandings left, where refinishing is not on the table at all. That is what the top of this page works out, and it is worth knowing before anyone quotes.
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About the author
Pablo Ruiz Quintero — Editor
Editor of MaterialsEstimator. Decides which documents count as a source, what every default value is, and where the line sits between what the reader parses and what the engines compute.
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