DIY GUIDE · TRADES & CONSTRUCTION · CHECKED OCTOBER 2026
How to sand and refinish a wooden floor yourself
A weekend. £348–£398 in machine hire, finish, masks and a scraper for a four-by-four-metre room.
Punch every nail, sand through the grits in order, keep the drum moving, and seal the room from the dust.
- Every step, start to finish
- Checked October 2026 — sources at the end
- Honest about when to call a pro
FIRST, THE HONEST ANSWER
Do it yourself, or get a builder?
Do it yourself if…
- The boards are solid timber, fixed down, and thick enough to take a sanding
- You can clear the room completely and seal it off from the rest of the house
- You are fit enough to steer a heavy machine for most of a day
- You can wait the drying time between coats before the room is used
Get a pro if…
- The floor is engineered board with a thin top layer, or has been sanded several times already
- The boards are painted at the edges with old paint that may contain lead, and it would have to be sanded off
- It is parquet laid in old black adhesive in a home built before 2000
- Boards are badly cupped, split or loose across much of the room, or need replacing
Safety first
- Wear a well-fitting FFP3 mask the whole time you sand, sweep or vacuum. Sanding wood with power tools produces a lot of fine dust, wood dust causes asthma, and the safety regulator expects a mask with a protection factor of 20 — FFP3 class — for most sanding indoors.
- Use the machine's dust bag and empty it often, and attach the extraction if the hirer supplies one. The less dust in the air, the less in your lungs and in the rest of the house.
- Treat any old paint on the boards as possibly containing lead if the house predates the 1960s. Do not dry-sand it; a council's lead guidance advises methods that make no dust or fumes, a P3 filter mask, and keeping children and pregnant women away from the work.
- Wear ear defenders and eye protection. A drum sander is loud for hours, and a nail head it catches can throw sparks and fragments.
- Never start or stop the drum with it lowered onto the floor, and keep the cable behind you and over your shoulder so the machine cannot run over it.
- Fine wood dust can burn. Empty the dust bag into a metal bin outdoors, keep it away from any naked flame, and never leave a full bag in the house overnight.
| MATERIAL | COVERAGE | FOR THIS JOB |
|---|---|---|
| Floor varnish or hardwax oil | Varnish 10–12 m² per litre per coat; one oil 30 m² per litre per coat | 16 m², three coats of varnish: about 4.4 litres, two 2.5-litre tins |
| Wood filler or slivers | As the gaps need | One tub, or a few lengths of slivers |
| Abrasives | Coarse, medium and fine for drum and edger | From the hire shop |
| Masking tape and dust sheets | To seal doors and cover vents | One roll and two sheets |
How much finish
36 m² of wall → 6.5 L for 2 coats. Buy about 7 L.
Floor area × coats ÷ coverage per litre, rounded up to whole tins. A 4 × 4 m floor is 16 m²; three coats of a varnish covering 11 m² a litre is 48 ÷ 11 = 4.4 litres, so two 2.5-litre tins.
Bare, freshly sanded wood drinks the first coat, so the first coat covers less than the figure on the tin. Check your own product's coverage and number of coats.
The drum sander does the open floor; the edging sander does the strip by the walls and under radiators. Hire them together for a whole weekend at least, because it always takes longer than you plan and returning a machine mid-job is no help. Ask the hire shop to show you how to load the abrasive and how to raise and lower the drum.
You will need coarse, medium and fine abrasives for both machines. The hire shop supplies them; one national hirer says sheets and dust bags are typically included, but check what you will be charged for. A floor in reasonable condition may not need the coarsest grade at all, while one with heavy old varnish or cupped boards will need it.
A hardwax oil soaks into the wood, looks natural, and can be patched in one area later; the one we looked at covers 30 m² per litre in one coat, needs two coats, and dries in 8–10 hours. A water-based floor varnish forms a harder film on top; the one we priced is touch dry in 20 minutes, can be recoated in 2 hours, and covers 10–12 m² per litre. Varnish is quicker to finish; oil is easier to repair.
Gloss shows every scratch and speck of dust that settled while it dried. Satin or matt hides wear better and suits most rooms. Whatever you choose, use the same product for every coat.
Gaps between boards can be filled with a wood filler, a resin mixed with the floor's own fine dust, or thin slivers of timber glued in. Filler suits small gaps; slivers suit wide ones. Some people leave the gaps, which is honest and lets the boards move.
Engineered boards have a thin real-wood layer that a drum sander can go through in minutes. If you cannot see how thick the top layer is, lift a threshold strip or an edge board and look before you hire anything.
THE PART THAT DECIDES THE FINISH
Preparing the floor — by what you start with
Most of a good sanding job is preparation. A single nail head left proud tears an abrasive sheet and gouges the drum's path, and a loose board chatters under the machine. Find your floor below and do its list before the machine arrives.
Floorboards that were under carpet
The commonest starting point.
- Lift the carpet, underlay and every strip of gripper, and pull out every staple and tack with pliers
- Go over the whole floor with a hammer and nail punch and set every nail head well below the surface
- Screw down any board that moves or squeaks
- Scrape off lumps of old paint, glue and underlay foam with a floor scraper
A varnished floor that has worn
Usually sands well; the old finish clogs abrasives fast.
- Check whether the old finish is varnish, wax or oil by rubbing a hidden spot with a little white spirit on a cloth — wax smears and softens
- Expect to start with a coarser grade to cut through thick old varnish
- Remove wax with a scraper and a wax remover first; wax clogs abrasive almost instantly
- Plan to change abrasive sheets more often than you think
Boards with painted edges
The old border round a rug; take care in an older house.
- If the house predates the 1960s and the paint is original, assume it may contain lead
- Do not dry-sand it. A council's lead guidance favours a liquid stripper, or a hot air gun set below 450C with the surface kept moist
- Wear a mask with a P3 filter, shut the room off and keep children and pregnant women out
- Clean up with a damp cloth and a vacuum with a fine filter, then bag the waste
Parquet or wood blocks
Sandable, but harder to sand well.
- Check every block is firmly stuck; refix loose ones before sanding
- Sand at an angle to the grain on the first passes, then follow the main direction of the blocks
- In a home built before 2000, do not sand through to any black adhesive: older floor adhesives and tiles can contain asbestos
- Use the fine grades with care; parquet shows cross-grain scratches more than boards
Boards that are cupped or have wide gaps
Sandable, with the right sequence.
- Check the boards are dry first; the oil maker we looked at wants no more than 18% moisture before finishing
- Sand the first pass diagonally to the boards with the coarse abrasive to flatten the cupping
- Fill or sliver wide gaps after the coarse pass, so the filler is sanded flush with the next grade
- Replace any split or rotten board with reclaimed timber of the same thickness before you start
THE JOB
How to sand and finish a wooden floor
Clear and seal the room
1 hourTake everything out of the room, including curtains. Tape plastic sheet over the doorway and across any vents, and close the doors to the rest of the house. Open a window for ventilation. Then go to the preparation section above and work through the list for your floor.
- Tape up gaps under doors; fine dust gets everywhere
- Remove or tape over smoke alarms in the room while you sand, and put them back when you finish
- Plan an exit that does not walk dust through the house
Mistake to avoid: Sanding with the door open to the rest of the house. The dust is fine enough to coat every surface downstairs.
Punch nails and fix the floor
1–2 hoursWork across the room board by board. Set every nail head well below the surface with a punch, screw down loose boards, pull out staples and tacks, and scrape off lumps of old glue or paint. Do the lead and asbestos checks for your floor type before any machine touches it.
- Run a gloved hand over every board; you will feel what you cannot see
- A magnet on a string swept across the floor finds hidden nail heads
- Mark any board you are unsure of with chalk
Mistake to avoid: Leaving one nail head proud. It rips the abrasive, can dent the drum, and leaves a scar across the floor where the machine jumped.
First pass with the coarse abrasive
2–3 hoursLoad the drum with the coarsest abrasive you need. Start with the drum raised, let the motor reach full speed, then lower it gently while already walking forward. Work along the boards, or diagonally on cupped boards, at a slow steady walking pace, and raise the drum before you stop at the end of each run. Overlap each run with the last by part of the drum width.
- Drum down only while you are moving; raise it before you stop
- Let the machine pull itself at its own pace — do not push or hold it back
- Change the abrasive as soon as it stops cutting cleanly
Mistake to avoid: Pausing with the drum down. It digs a hollow across the boards in seconds, and the only way out of it is to sand the whole floor down to its level.
Edges with the coarse abrasive
1 hourFit the edging sander with the matching coarse disc. Keep it moving in smooth arcs along the skirting and around the room, blending into the area the drum has done. Hold it level and never let it rest in one place.
- Keep the edger moving all the time it touches the floor
- Work with the grain where you can, blending into the drum's area
- Take care against skirting and pipes; it marks them quickly
Mistake to avoid: Tilting the edger. It cuts swirled grooves that show clearly once the finish is on.
Fill the gaps
1 hourVacuum thoroughly. Fill nail holes and small gaps with filler mixed with fine dust from the bag, or glue slivers into the wider gaps and trim them flush once the glue has set. Let filler dry fully before the next pass.
- Collect fine dust from the bag for colour-matched filler
- Press filler in firmly and leave it slightly proud for sanding back
- Glue slivers on one side only so the boards can still move
Mistake to avoid: Filling before the coarse pass. The coarse abrasive digs the filler back out, and you end up doing it twice.
Second pass with the medium abrasive
1–2 hoursVacuum again. Change the drum to the medium abrasive and sand along the grain of the boards, with the same rule of lowering and raising the drum only while moving. Then do the edges with the medium disc.
- Always sand along the boards on this pass, never across
- Vacuum between grits so coarse grit does not scratch the floor on the finer pass
- Look across the floor in raking light from a window to see scratches
Mistake to avoid: Skipping a grit to save time. Each grit only removes the scratches of the one before; jump one and the coarse scratches show through the finish.
Final pass with the fine abrasive and hand scraping
1–2 hoursFit the fine abrasive and make the final pass along the grain; the oil maker we looked at asks for a final sanding at P120–150 before oiling. Do the edges with the fine disc, then scrape the corners and under radiators by hand with a sharp scraper, followed by a sanding block. Vacuum everything, including the skirting tops and window sills.
- Scrape along the grain in the corners, never across it
- Check the edges blend into the main floor in raking light
- Vacuum twice and wipe with a barely damp cloth to lift the last dust
Mistake to avoid: Leaving dust on the skirting or sills. It falls onto the wet finish as you work and sets in it.
Apply the first coat
1 hourStir the finish well. Starting in the corner furthest from the door, work along the boards in the direction of the grain, a few boards at a time, keeping a wet edge so new strokes run into finish that is still wet. Apply thin, even coats; too much and it dries slowly or unevenly.
- Plan your route so you finish at the door
- Work in good light so you can see missed patches
- Keep the room ventilated but free of draughts carrying dust
Mistake to avoid: Painting yourself into a corner, or flooding the boards. Thick finish dries slowly, stays soft and can wrinkle.
Denib and apply the next coats
1 hour a coatWait the full recoat time on the tin. Water-based varnish often raises the grain on the first coat; rub it down lightly with a fine abrasive pad, vacuum, and apply the next coat. Repeat for the number of coats your finish specifies; the oil we looked at needs two thin coats, applied once the first has dried for 8–10 hours.
- Rub down lightly between coats, along the grain
- Vacuum and wipe before each coat
- Keep the same batch of finish for every coat
Mistake to avoid: Recoating before the previous coat has dried. The coats do not bond and the finish stays tacky or peels.
Let it cure before using the room
1 dayKeep people and pets off until the finish is hard enough to walk on in socks, then wait longer before bringing heavy furniture back and longer still before laying rugs. The oil we looked at takes 2–3 weeks to cure fully; follow the times on your own product.
- Lift furniture back in, never drag it
- Put felt pads on every leg before it goes down
- Leave rugs off until the finish has fully cured
Mistake to avoid: Putting a rug down on a new finish. It traps the curing finish and can leave a mark the shape of the rug.
The mistakes that show
- Stopping with the drum lowered, which digs a hollow across the floor
- Leaving nail heads proud, which tears abrasives and scars the boards
- Skipping a grit, so coarse scratches show through the finish
- Dry-sanding old paint that may contain lead
- Recoating too soon, so the finish stays soft or peels
Stop here and get a floor sander
- The floor is engineered board and you cannot confirm the top layer is thick enough to sand
- Old painted borders may contain lead and would have to be sanded off rather than stripped
- Parquet sits in old black adhesive that could contain asbestos and the sanding would reach it
- Many boards are split, rotten or loose and need replacing before any sanding
| WHAT YOU SEE | WHY, AND THE FIX |
|---|---|
| Dips or chatter marks across the boards | The drum was lowered or held still in one place, or the machine bounced over a loose board. Fix the board and sand the area again with the medium abrasive, feathering out well beyond the mark. |
| Swirl marks near the skirting | The edging sander was tilted or held still. Sand again with a finer disc kept moving, then scrape by hand along the grain. |
| Scratches showing through the finish | A grit was skipped or the floor was not vacuumed between grits. Sand back to bare wood in that area with the missed grit and work through the sequence again. |
| The finish is rough with little bumps | Dust settled in the wet finish, or the grain raised after the first water-based coat. Rub down lightly with a fine abrasive pad, vacuum and apply another coat. |
| Patches look darker or blotchy | Uneven sanding, or filler that took the finish differently. Sand the patch evenly to bare wood and refinish it; colour-matched filler from the floor's own dust helps. |
| The finish is still tacky after a day | Coats too thick, too cold or not enough ventilation. Improve ventilation and warmth and wait; if it does not harden, it has to be sanded off and redone. |
| Gaps reappeared after winter | The boards shrank as the heating dried them. This is normal in timber; flexible filler or slivers glued on one side cope with it better than rigid filler. |
| The finish is peeling | It was applied over dust, wax or an old finish not fully removed, or recoated too soon. Sand back to bare wood in the area and refinish. |
WHAT YOU SAVE
What it costs to do it yourself
| Drum and edging sander package, a week's hire | £245.56 |
|---|---|
| Floor varnish, two 2.5-litre tins | £77.58–£102.18 |
| FFP3 masks | £4.48–£29.99 |
| Floor scraper | £19.99 |
| Total | £348–£398 |
| DIY total | £348–£398 |
Guide prices compiled by the Locufy team from published Irish and UK provider price lists and 2026/27 cost guides. Updated 2026.
Hire rates vary by depot and some charge for abrasives by use; one national hirer quotes a floor sander from £88 a day. A professional floor sander's price per square metre, from the price guide, is shown alongside.
RATHER NOT?
Floor sanders near you, with prices shown
The ones who cover your area, nearest first, with one score from every review. No account needed to look.
Or post the job free and let them come to you.
Light use once it is dry to the touch, but no rugs, no heavy furniture dragging and no wet mopping until it has cured to the time on the tin.
Bagged sanding dust goes in general waste once it is cold and damp. Part-used tins of finish go to your council's household waste and recycling centre; one council accepts up to 5 litres of household chemicals a month, and empty dry tins go in the metal recycling. Never pour finish down a drain.
Empty the dust bags outside into a metal bin, wipe the machines down and return unused abrasives if the hirer refunds them.
Felt pads on furniture, a mat at every outside door, a dry vacuum most of the time and a barely damp mop with the finish maker's cleaner when it needs more.
Sanding and finishing a wooden floor: questions people ask
Yes, with hired drum and edging sanders, if the boards are solid, fixed down and thick enough. The work is hard and dusty, and the two rules that matter most are punching every nail below the surface and never leaving the drum lowered while it is standing still.
Start with the coarsest grade the floor needs, then medium, then fine, without skipping any. The hardwax oil maker we looked at asks for a final sanding at P120–150 before the first coat.
Varnish gives a harder film and is quicker to finish; the water-based one we priced can be recoated after 2 hours. Hardwax oil looks more natural and can be patched in one area, but takes longer — 8–10 hours a coat for the one we looked at.
Not by dry sanding if the paint could contain lead, which was used in some paints until the mid-1960s. A council's lead guidance recommends stripping methods that make no dust or fumes and a P3 filter mask.
You can usually walk on it in socks once the last coat is dry, but heavy furniture and rugs should wait until it has cured; the oil we looked at takes 2–3 weeks to cure fully.
The Locufy UK price guide puts professional floor sanding at £20–£45 per m², typically £30 — the same three figures as the strip at the top of this page.
MORE GUIDES
More DIY guides
Sources — checked October 2026
- HSE — construction dust: cutting and sanding wood (on-tool extraction, FFP3 with a protection factor of 20 for most sanding)
- Osmo UK — Polyx-Oil Original: 30 m² per litre one coat, two coats, 8–10 hours drying, 2–3 weeks to cure, wood moisture max 18%, final sanding P120–150
- Toolstation — water-based floor varnish product page: touch dry 20 minutes, recoat 2 hours, 10–12 m² per litre, £38.79 for 2.5 litres
- Cambridge City Council — lead paint in your home: lead in some paint until the mid-1960s, hot air gun below 450C, P3 filter mask
- UKHSA on gov.uk — asbestos general information: floor tiles and adhesives, homes built before 2000
- North Northamptonshire Council — what can be recycled at household waste recycling centres (wood, up to 5 litres of household chemicals a month)
- National Tool Hire Shops — floor sander hire: from £88 a day, floor and edging package £245.56 a week, abrasives typically included
- Toolstation — floor finishes price check: floor varnish £38.79–£51.09 for 2.5 litres
- Toolstation — face masks price check: FFP3 £4.48–£29.99
- Toolstation — flooring tools price check: floor scraper £19.99