Updated November 6, 2026
Four kinds of marks
| What you see | Where it sits | What refinishing can usually do |
|---|---|---|
| Fine, light scratches that look white or grey | In the finish coat | Often improved by a recoat or removed by sanding |
| Small dents from claws or dropped objects | Compressed wood fibres | Shallow ones may reduce with sanding; deeper ones often remain visible |
| Dark grey or black patches | Inside the wood, from repeated moisture or urine | Frequently lighten only partly; may need other work beyond sanding |
| Soft spots, lifting edges or a lingering odour | Possibly below the surface | Cause needs investigating before any cosmetic work |
Finish scratches versus wood damage
Running a fingernail across a scratch gives a clue, not proof. A pale mark your nail glides over is often confined to the finish; a groove that catches and shows a different colour may have reached the wood. Depth needs to be confirmed on site. Scratches confined to the finish may respond to a recoat or a refinish. Scratches in the wood need sanding below their depth, which works for shallow marks but uses up wood each time.
A new finish protects the surface, but it does not harden the wood beneath it or stop a heavy dog from denting a soft species. Matte and satin sheens tend to show fine scratches less than gloss; our sheen guide explains why.
Dark stains: the honest limits
When liquid soaks repeatedly into bare or worn wood, it can react with the wood and darken it well below the surface. Sanding removes the top layer evenly across the floor, so a stain that goes deeper than that will still show. Sometimes it fades enough to blend with a darker stain colour; sometimes it does not. Nobody can promise removal before the floor has been sanded and the result seen.
Where a stain cannot be sanded out, the boards themselves may need attention. That is separate work from sanding and refinishing, and it is worth getting advice on it before planning a colour.
Odour and moisture come first
A persistent smell, cupped or raised boards, or a soft spot are reasons to investigate before refinishing. Odour alone does not show where moisture is or whether it reached the layers beneath, so have the cause checked by a suitable professional first. Refinishing the surface will not deal with an underlying moisture problem.
What not to try first
Avoid bleach, ammonia, steam mops and strong household chemicals on a finished wood floor. Finish makers such as Bona advise cleaning with a dry or lightly damp microfibre mop and a cleaner made for the finish, and wiping up spills promptly (Bona cleaning guidance; Bona maintenance instructions). Felt pads under furniture and regular nail trimming also reduce new marks.
Photos and history that help
- One wide photo of each room so the pattern of wear is visible
- Close-ups of the worst stains and scratches, with a coin for scale
- Photos in daylight and with your usual room lighting
- How long the stains have been there and whether any area feels soft
- Whether pets will be at home during the work
Describe the floor in the estimate form, then email the photos to info@hardwoodfloorrefinishingottawa.ca or attach them to your reply to our response. Floor condition may need assessment to confirm scope and pricing, and we will tell you plainly what sanding is likely to improve.
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