Hard Wood Floor Cupping!!

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Husky

Feeling the Heat
Nov 2, 2014
351
Rochester, NY
Noticed yesterday that my Bamboo hard wood floor is cupping to the right of the pellet stove. It is on about 6 boards wide and about 6 feet long. I had this floor installed 2 years ago. We had a wood stove last year and installed a new pellet stove this year. Last year we burned wood all year without a problem. The cupping has just started in the past week or so. I know it must be because of the RH levels in the room but I am surprised it didn't happen last year if it was going to happen at all. Not sure what to do to get the cupping to reverse itself or if it will at all. Has anyone out there ever had this problem and what did you do to fix it? Any advice would be much appreciated.
 
How wide are the planks? Nailed like a real hardwood floor?
 
Typically once flooring cups it's not going back...unfortunately there is no quick fix....could be an install problem but unusual just in that area...Moisture, or excessive heat, drying, could be the cause......what is the floor installed over.
 
How wide are the planks? Nailed like a real hardwood floor?
The planks are 5" wide and they are nailed down just like hardwood.
 
Typically once flooring cups it's not going back...unfortunately there is no quick fix....could be an install problem but unusual just in that area...Moisture, or excessive heat, drying, could be the cause......what is the floor installed over.
I would guess from drying. I just went and got a meter to measure RH in my family room and the air is 33%. The floor is laid on subfloor and 1/8 luan.
 
The planks are 5" wide and they are nailed down just like hardwood.

5" wide is very wide for any board.. Not familiar with the structural integrity of Bamboo though.
 
Engineered flooring shouldn't warp. It's fancy plywood. What's happening to the subfloor?

I think with solid wood flooring it depends on the condition of the flooring before the trauma. I've got some t&g flooring in my cabin that buckled in the center from wood expansion after the lake flooded. It was under 16" under water for a few days. It finally flattened completely again this winter. The flood was in 2011. It had laid flat since 1952. I'm not sure how much damage was caused by prior times that the water came over the floorboards, but it was flat in 2010.
 
Engineered flooring shouldn't warp. It's fancy plywood. What's happening to the subfloor?

I think with solid wood flooring it depends on the condition of the flooring before the trauma. I've got some t&g flooring in my cabin that buckled in the center from wood expansion after the lake flooded. It was under 16" under water for a few days. It finally flattened completely again this winter. The flood was in 2011. It had laid flat since 1952. I'm not sure how much damage was caused by prior times that the water came over the floorboards, but it was flat in 2010.

Is it an engineered flooring plank (plywood)? I missed that part. How thick is it?
 
Engineered flooring shouldn't warp. It's fancy plywood. What's happening to the subfloor?

I think with solid wood flooring it depends on the condition of the flooring before the trauma. I've got some t&g flooring in my cabin that buckled in the center from wood expansion after the lake flooded. It was under 16" under water for a few days. It finally flattened completely again this winter. The flood was in 2011. It had laid flat since 1952. I'm not sure how much damage was caused by prior times that the water came over the floorboards, but it was flat in 2010.
Sub floor from basement looks fine.
Is it an engineered flooring plank (plywood)? I missed that part. How thick is it?
It is engineered but made with bamboo grass. It's not like your engineered hard woods made out of plywood. Its 5/8" thick. I believe the process is they take the bamboo and laminate it together just like they make plywood and several layers.
 
It could be the laminate glue is not liking the constant exposure to heat.

I have a new red oak hardwood floor that is in close proximity to our pellet stove. When I install a wood stove in that location, i'm going to set the stove farther back and raise the hearth, to help keep heat off the floor.
 
It could be the laminate glue is not liking the constant exposure to heat.

I have a new red oak hardwood floor that is in close proximity to our pellet stove. When I install a wood stove in that location, i'm going to set the stove farther back and raise the hearth, to help keep heat off the floor.
I just went out and bought a whole room humidifier that will pump 9 gallons of water into the air over a 24 hours. Going to get RH up to see if it relaxes the boards a little. I know I probably won't see a big difference until summer when we have high humidity but maybe can stop other boards from doing the same.
 
My guess is ice dams on your roof.
 
I just went out and bought a whole room humidifier that will pump 9 gallons of water into the air over a 24 hours. Going to get RH up to see if it relaxes the boards a little. I know I probably won't see a big difference until summer when we have high humidity but maybe can stop other boards from doing the same.

Don't go crazy man! You don't want to cause another issue while trying to fix another.
 
Why do you say that? This is the first year I have had ice dams.
I don't think your humidity is too low.
I think you have ice melting on your roof and the water is running inside your wall then seeping out under the floor.
You can't see it. You can see the evidence though.
It isn't because of your pellet stove.
If it was it would have happened last year.
The humidifier will make it worse.
Take care of your gutters and your roof first.
 
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I don't think your humidity is too low.
I think you have ice melting on your roof and the water is running inside your wall then seeping out under the floor.
You can't see it. You can see the evidence though.
It isn't because of your pellet stove.
If it was it would have happened last year.
The humidifier will make it worse.
Take care of your gutters and your roof first.

Dude, you get an award for pulling that answer out of almost nowhere. With no pics and very little information to go off of you may very well have hit the nail on the head. Obviously you have run into this before but damn that's almost freaky
 
I've run but never owned a pellet stove and as I understand it they heat the air an blow it around. You will get extra hot in the room but there is no searing radiant heat like from in front of a real woodstove rocking at 800 with no air movement. Seems a pellet stove could not ruin the floor right next to it unless the whole room's floor was ruined.
 
Dude, you get an award for pulling that answer out of almost nowhere. With no pics and very little information to go off of you may very well have hit the nail on the head. Obviously you have run into this before but damn that's almost freaky
Well, thanks but it was fairly obvious.
Clearly the pellet stove didn't do it. The much more likely culprit is water. He doesn't see water yet ice dams have been melting all week.
 
I don't think your humidity is too low.
I think you have ice melting on your roof and the water is running inside your wall then seeping out under the floor.
You can't see it. You can see the evidence though.
It isn't because of your pellet stove.
If it was it would have happened last year.
The humidifier will make it worse.
Take care of your gutters and your roof first.
I will investigate this when I get home tonight. The boards that are showing the cupping are not next to the outside wall but in about 10-12 boards from the wall. It is also would have to travel down the second floor wall and the first floor wall before hitting the down stairs wall. The subfloor from the basement view looks normal without and signs of moisture. I am going to get a moisture meter and check subfloor from basement to see if there is a variance of moisture readings. I will post some pictures tonight to show what is going on to help show my issue. Thanks for the input and possible cause.
 
I will investigate this when I get home tonight. The boards that are showing the cupping are not next to the outside wall but in about 10-12 boards from the wall. It is also would have to travel down the second floor wall and the first floor wall before hitting the down stairs wall. The subfloor from the basement view looks normal without and signs of moisture. I am going to get a moisture meter and check subfloor from basement to see if there is a variance of moisture readings. I will post some pictures tonight to show what is going on to help show my issue. Thanks for the input and possible cause.
Well it is unlikely then unless your house is balloon framed.
Good luck.
 
It sure does sound like moisture, not heat. Bamboo flooring is usually known for it's stability. Often the better quality bamboo flooring is approved for damper areas like basements. It needs to have all layers made of bamboo though. We installed it upstairs about 11 yrs ago. It still looks like new and is very flat. It sounds like the substrate may not be bamboo and it is failing.
 
Okay, took a picture of floor to show what is happening. It is hard to see but if you look at boards closest, you can see that the boards are raised at the joints and lower in the middle. You can see board farthest away look flat.
I have looked for moisture every where but can not see where it could possibly be coming from. Wall to right, where you can see edge of mantel, is shared wall with attached garage. Wall to back, where light is coming from bay window, is about 10 boards away from cupping.

20150317_165656.jpg
 
Condensation on the underside of the flooring due to a large temp difference?

Also, is that the stove to the left with no hearth pad?
 
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