Is It Possible to Repair Gaps in Floorboards?

When there are honest-to-goodness gaps between floorboards, there isn't a whole heck of a lot you can do about it. Really old wood floorboards can expand and contract over time, and splinters can pull away between the floorboards. Overly-sanded floorboards can develop greater gaps. There are many reasons.

As an aside: if you have or want wide plank flooring, gaps are part of the aesthetic.

Gaps are why many people just decide to lay down a new substrate and then install an entirely new wood floor on top.

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