We have a 15 year old plank floor with a dark brown painted surface. The planks have shrunken, leaving uneven gaps between the boards ranging from 1/8″ to 1/2″ along the length.
I would like to paint and seal this floor but need to find an effective way to fill the gaps. Is there any type of liquid or paste filler that could be successfully applied before sanding and painting the floor?
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Replies
It is difficult to fill such gaps because they wax and wane with the seasonal humidity. Anything rigid you put in the cracks will either fall out in the dry part of the winter as the boards shrink, or crush and pop out during the humidity of the summer when the boards expand. And it is difficult to put any paste in there without it falling through the cracks, as the expression goes.
For the large gaps you could cut wooden strips, and leave the smaller gaps alone. I have seen on TV where someone used rope to fill the cracks. That's a look you'd have to like, though.
Thanks for your help. I have heard about the popping out before but wondered if some silicone type filler might be flexible enough to try. Rope sounds pretty cool, but since the gaps are not uniform in size, it probably wouldn't work on this floor. Jjet
Caulking may work if it doesn't run out the bottom, but the look is not to everyone's taste. Silicones are not paintable, thus a poor choice.
You might want to post this in the breaktime forum too, that is the building/contractor forum. (3 over to the left up top, from the house chat)
You cannot put in anything that is rigid, even wood because when the flooring expands it will do whatever it needs to to grow. Wood does not expand along the length of the flooring, it is all across the grain of the boards. The only thing I've ever heard of it the general contractor on "this old house" Tom Silva filled the gaps on a floor with rope. It wasn't the the nylon white rope, it was a browned, natural rope that he laid in the seems and pushed it in. That will flex and keep dirt and crap out. That is probably your best bet though, my flooring contractor told me "that is the character of wood flooring, and there is nothing you can do to fix the gaps"
Also, if you do use the rope, now is a pretty good time to put it in because the humidity is still low and the wood has not expanded yet.
Thanks for taking the time to offer this suggestion. I'll look into some rope sizes and see what we can do! Much appreciated. Jjet
I found this for you from this old house. They have an article in the magazine too but that is for pay subsribers only. If you can find the issue the article is in, your local library will probably have the past 4 years of issues. http://www.thisoldhouse.com/toh/tvprograms/asktoh/showresources/episode/0,16663,421656-429070,00.html
Season 1 | Episode 104
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Original Air DateWeek of October 31, 2002
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and this
Hardwood Floor GapsI am repairing hardwood floors in my home. I would like to fill the gaps between the boards. Is there a product for this job?
— Trisha, West Chester, OH
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Tom Silva replies: You can apply wood filler to fix the gaps, but this can be a temporary fix. When the floor contracts, the filler can pop out; or, when it expands, it can fall in, unable to span the wider gap. In the Milton House, the gaps in the floorboards were so wide that we filled the seams with rope and then stained it to match the floor. This is an old technique that's quite smart; the rope expands and contracts with the rest of the floor and the gaps stay plugged, keeping drafts to a minimum. To properly fix your problem, you need to determine why your floors are gapping.
Dday,
Once again thank you for your help. Jjet
Besides rope you could use "oakum"--plumbers used to use it to seal lead or cast iron pipes--it's also used in shipbuilding between planks in the hull as it expands when it gets wet.
The other thing that might work is called "caulk backer" and is a compressible foam rod that comes in various diameters. It comes in a coil and you unwind it and press it into the wide crack and it helps the caulk bridge the crack.
The only problem I see with any of these is that when the boards are at their widest, they will compress these fillers and make them protrude from the cracks--may be a trip hazzard.
Thanks for the ideas. We live in a really, really dry climate but do have a humidifier on our furnace. Nonetheless, our average humidity is below 40%, so that might work, though the idea of it protruding at times is not very appealing. Jjet
I suppose if you pushed either rope or caulk backer rod into the cracks when they were as closed as they get and make sure it doesn't stick up, then when the boards shrink, the rod will decompress and be somewhat inletted below the surface and wouldn't cause tripping. You could perhaps just caulk the narrow cracks when they are closed and the caulk will probably stretch as they, open and the big cracks could have the rod covered with caulk if there is room, otherwise just the rods or rope. Rope may not protrude because it is lesh "squishy" and compressible.
I don't think the oakum would be a very good choice, oakum is oiled hemp. One of my best friend's is a plumber and I've worked with him through the years and oakum looks like old dirty dreadlocks. It works great for cast iron plumbing waste runs but thats about it. Also, the foam would work in the short term but I think over time it would break down some since foam doesn't do very well when it is in a wear area. Also, those backing rods are almost always a light color which would be very visible in between hardwood.
I have tried the jute rope idea and it will also need some glue or silicone to hold it in place. The gaps are neither uniform in width, not in depth - a bit of adhesive or silicone will make the job go faster. However, I think the rope has a certain appeal, and it will be painted and then varathaned to finish it off, so as long as the rope is slightly below the level of the planks, I think the floating up or tripping problem will be avoided.
The floor is not hardwood - it's a botched plank floor. The original light colored stain was destroyed by careless workmen, so the floor has been painted dark brown. The intent is to fill the cracks, then make a new style of paint finish, then seal the floor.
Thanks again for your help. Jjet