The problem is magnified if 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.
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Although some gapping is inevitable, severe gaps become more than just unsightly.
Should You Fill Flooring Gaps?
In extreme cases, floorboards can buckle if you have left no room for them to expand.
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If you’re certain the gaps are there year-round, it’s probably safe to fill them.
It’s best to do this during the humid season, when the gaps are most narrow.
Depending upon the option you choose, you might not need all of the supplies on our lists.
Read through the instructions carefully, then gather the supplies and tools appropriate for your chosen method.
Need more help?
Cut the Strips
Measure the width and length of each gap between floorboards.
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Set up a table saw to rip-cut strips to the measured width.
Cut the strips as needed for the length of the gap to fill, using amiter sawor handsaw.
give a shot to cut the strips from the grooved side of the spare floor board.
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take a stab at get the strip flush with the adjoining boards.
Wipe away excess glue with a damp cloth, then let the glue dry.
Stain and/or finish the strips to match the rest of the floor.
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Be careful not to damage the edges of the adjoining floorboards.
Vacuum the loose debris from the gaps with a shop vacuum.
Repeat scraping and vacuuming until the gaps are clear.
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Pour wood stain chosen to match the tone of your floorboards into a small bucket.
Dunk the rope into the stain so it is saturated.
Carefully pull out the rope, letting the excess stain drip back into the bucket.
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Stretch the stained rope out on clean cardboard and let it dry completely.
Trim the rope as needed with a sharp utility knife.
Clean the Floor
Clean the floorboardson both sides of the gap, using a slightly dampened cloth.
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Remove excess putty from the wood surface using a putty knife.
Be careful not to scratch the floor’s finish.
Choose a wood putty that is similar in color to the floor boards.
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Take care not to pull putty out of the gap.
Let the putty dry completely before walking on the floor.
To give the surface more strength, apply a coating of varnish or polyurethane.
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This also will likelyhelp it blendbetter with existing flooring.
What is Peaking, Buckling and Cupping in Wood Floors.
Table Saw Safety and Operation.
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Coatings and Colors Manual.
United States Department of Homeland Security.
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