Filling cracks in wood floor

Q: I have a hard maple wood floor that’s 80 years old. The boards are 1 1/2″ wide and have shrunk from 1/32″ to 1/4″ inch. Is their a way to fill the cracks?

Will it look natural when finished?

A: Timbermate is likely your best choice of wood filler for this floor. You should contact them for further direction.

Lots of cracks between boards

Q imported from our old site, Face Lift Floors: Our problem is that the flooring seems to have lots of cracks between the boards, and somebody in the past put a lot of nails in the boards in the hallway. Can we putty this or is there a better way to repair it?

A: Small gaps about the width of a dime would be considered normal gaps. This condition is lessened with good climate control in the home. Also, excessive moisture applied to the wood will cause some swelling in the boards. After they dry and stabilize, there will be gaps. If you are having your floors re-sanded anyway, then the sander should fill all these cracks with a spreadable wood filler. I use water based types. They don’t have the nasty chemical effects on the worker, and they stick pretty well.

If there are any really large gaps, and you have some movement (up and down) between boards, I have found applying carpenters glue from a squeeze bottle into the gap will hold both boards, side by side, stable, so the filler will not crack out after. The nail holes can be filled with the same wood filler but must be set first.

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1″ Cracks between boards

Q imported from our old site, Face Lift Floors: We have (about 1″) cracks between the boards of our 1850 pine floors, we would like to fill them, but do not want to sand/refinish the floors (as they had been a few years back) any suggestion?”

A: 1″ cracks you say! That is not a crack. That is a big gap. Can I assume that this is not tongue and groove, and there is no subfloor beneath this pine?

What I am thinking is that you could make a stiff paste with fine wood dust and wood glue and press it into the gaps. I am not sure that it would not sink through. It would have to be really a stiff mix. Perhaps jamming some paper into the gaps first or cutting tight fitting wood strips and banging them in would give this paste something to sit on. Before doing this, I would apply painters tape to each side of the gap so you don’t smear the glue-dust mix all over the surface of the floorboards.

If the color is going to be significantly different, make sure you push the mix below the top of the boards so that when it hardens you can perhaps apply another color matched latex filler on top. Then when all of that is done, you may want to have the floor lightly buffed with a polisher and fine screen pad, and recoated.

If you can come up with a more workable solution, please let me know. I hope this helps.

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