With older tongue-and-groove hardwood or even wide plank floors, gaps inevitably develop between the boards. The problems with this are numerous. First, it is unsightly and it makes it difficult to clean because these gaps become dirt magnets, but they also present a dangerous hazard, because if they become uneven, it’s possible to trip on the curled edges. If you have floors acting like this, you might want to have them fixed. How do you do it?
First of all, do the nickel test! If you can fit a nickel on-end into any of your gapped floorboards, you may have a developing problem that needs to be fixed ASAP.
How Floorboard Gaps Develop
Gapping is a common problem with older wood flooring as the wood shrinks over time. The problem is magnified when the boards were not tightly laid in the first place. Another exacerbating condition is water damage. Water-logged wood will first swell then shrink as it dries out. Floors that have excessive heat below, as in the case of a furnace room, are particularly prone to developing gaps because of the dry heat they are subjected to.
Should You Fill Your Gaps?
It’s important to keep in mind that all wood expands and contracts with seasonal humidity changes. If you’re bothered by gaps in the dry winter months but don’t seem to notice them much during the relatively humid seasons, it’s probably best to leave the gaps alone, as filling them when they’re at their widest will create problems when the wood expands again and the gaps close up. In extreme cases, floorboards can buckle if you leave no room for them to expand.
On the other hand, old flooring can develop gaps that are more or less permanent, although they still may get slightly wider and narrower with humidity changes. If you’re certain the gaps are there year-round, it’s probably safe to fill them. However, it’s best to do this during the humid season, when the gaps are most narrow. That way, you can’t fill them too much and leave them with no expansion space. Of course, this means you might see slight gaps when the wood shrinks again next winter. Alas, wood is what it is, and you can’t change nature.