Replies

1. 
   ring | Aug 09, 2010 01:09pm | #1

   need lots more info

   You've gotta tell us a lot more in order to even guess what the problem might be...

   What's the subfloor made of?  Is it above grade or below?  How did you attach the hickory flooring to the subfloor?  Nails, adhesive? Was the flooring wrapped in plastic while it was sitting in the garage?  Is it solid hickory, or lamination?  Was there a change in humidity since you laid it?

1. 
   yyoouu99 | Aug 09, 2010 02:38pm | #2

   more info

   I am not exactly sure what the subfloor is made of, its a plywood of some sort.  The floor is above grade.  I attached it with nails through the tongue.  It is solid hickory that was packaged in plastic and the covered in cardboard.  The humidity hasn't changed its been high ever since.  The only thing that has changed is that I laid it on a weekend and we had all the windows and doors open.  During the week all the windows and doors were closed and the south wall is mostly windows.  If you need more let me know.

1. 
   ring | Aug 09, 2010 05:14pm | #4

   getting there...

   You said that the floor boards are cracking lengthwise, which is hard for me to understand 'cause if they are nailed only thru the tongues, why wouldn't they each just pull away from the next a bit instead of cracking?  I would have guessed that being kept in plastic they would have kept a low MC until you installed them, then picked up the humidity in the air and are now trying to expand.  But this would cause the floor to buckle in spots, which is not what you're describing, unless your Mom's description is misleading.  Get her to post you a photo close-up of what is going on.  It doesn't make sense to me...

2. 
   zolton | Aug 09, 2010 05:09pm | #3

   "Cracking lengthwise?"

   What, exactly, does "cracking lengthwise" mean? Are the individual pieces of hickory splitting randomly? Or are gaps developing between the pieces, where the tongue and groove joints are?

   Either way this is a very problematic circumstance. If the wood had been stored in the garage for any length of time, it absorbed moisture from the humid air out there and swelled. If you lay it in that state and it subsequently dries out (as it certainly will during the winter) the boards will shrink and large gaps will develop between the pieces.

   The fact that this might be occuring now, while it is still summer and the air is humid and your mother has the windows open, is not a good sign. In the winter the shrinkage - and gaps - will become much more severe.

   You were correct with your initial inclination to break open the bundles of flooring and scatter the pieces about in the house for several days before it went down. That would have given the wood a chance to acclimate to the humidity level inside the house. And, even though there might still have been some shrinkage due to the fact that it has been a very humid summer everywhere, it would not have been as bad as it is going to get.

   Sorry to be the bearer of ill tidings, but this is a situation about which a lot of knowledge has been accumulated over the years, and it is pretty predictable what is going to happen - and how it could have been prevented.

   It would seem to be a near impossibility that the individual boards are splitting, as they are only fastened along one edge - the tongue. The other edge of the board, bearing the groove part of the joint, should be free to slide back and forth over the tongue of its adjacent neighboring board. But until you answer back about the exact nature of the cracking, we need to keep an open mind.

   Zolton

1. 
   yyoouu99 | Aug 10, 2010 07:39am | #6

   random boards are cracking lengthwise in the boards.  the cracks are going with the grain.

1. 
   zolton | Aug 10, 2010 07:59am | #7

   Lengthwise cracking

   This is unusual, then. How many boards are affected?

   Unless the boards were cracked to begin with and, in drying after being laid, they pulled apart due to decreasing humidity in the environment, I can think of only one other circumstance where this might occur. And that would be if the boards were cupped and someone walked across them and cracked them that way.

   I just reread the orginal post and realized this is a new house being built. New houses are notorious for having very high moisture content as the concrete cures out  and framing lumber and floor decking gives up moisture. Could it be that laying the flooring on a moisture-laden subfloor caused the flooring to cup? I've seen that in some cases where it was installed over a damp crawlspace. The flooring can easily absorb moisture from the subfloor. Each board would have raised edges and a depressed middle. Walking on the floor while it was in that state might cause some of the boards to crack. Did your mother mention anything about the flooring cupping?

   Zolton

3. 
   hammer1 | Aug 10, 2010 01:20am | #5

   Its very difficult to lay 4"

   Its very difficult to lay 4" hardwood, strip flooring over a large area and not have both shrinking and swelling cause some joints between the boards to open and close with seasonal changes. Unless the house can be kept at a constant humidity level, you are going to have movement.

   For you to have movement in a few days, there is a significant difference in the humidity level from the garage to the house. Even though the flooring may be pre finished and in plastic, the cells of the wood do their thing. Just moving the flooring into the house for a few days may not be enough. If the humidity level in the house is high, the flooring will just acclimate to that level.

   Most knowledgeable flooring installer use a moisture meter to take readings of both the flooring and subfloor, looking for 7-8%. They also set up a hygrometer, run a dehumidifier and try to attain 40% humidity. The packages of flooring have to be opened up, stacked loosely with stickers and allowed to stay in the room until conditions are ready. These are the best conditions to guard against future shrinking of the boards.

   The issue will always be maintaining a proper humidity level in the house. Not so easy in all parts of the country year round. If the level climbs above 50% you may get buckling, if it drops below 30% you will get shrinking. Each board is an individual and some may like to move more than others. Absolute perfection isn't something solid wood is going to cooperate with over the long term. Try to establish the best installation environment and try to maintain consistent humidity in the house. If humidity can't be controled in the house over the seasons, choose a stable species that will move less. Hickory has a very high coefficient of  dimensional change.

4. 
   JustAbout | Aug 10, 2010 02:17pm | #8

   If I understand correctly, the way you are laying the floor, the room is about 17 feet wide and 60 feet long?  (1000 square feet divided by 60 feet.)  If your numbers I read are correct, laying the floor in this direction is asking for trouble, and doing so requires very careful preparation and skill.  It would be a great room for parquet, for example.  Or perhaps starting at the center of the room and working two directions.  4 inch-wide boards are going to be a problem if the Relative Humidity on all sides of the floor boards isn't pretty constant.

   I had a second concern as I read your note and the various comments.  Did you leave space between the ends of the boards and the wall?  If you did not, that could explain the splitting.  As the boards moved, the ends could have wedged against the wall, causing cracking.  This is one of the common beginner's mistakes: not leaving adequate perimeter expansion space, especially in doorways. While it is true that boards don't expand or shrink much in length, they do move: perhaps .1%, or about 3/32 inch in 8 feet or 3/16 inch in 16.  The longer the lengthwise run (60 feet is not unusual in a house) significant expansion can occur (shrinkage isn't a problem).  This can often be compounded by trash working its way into the perimeter space and then working as a wedge (nails are typical problems).

   More than one event may have occurred.  Was a release material (e.g., 15# felt) applied between the plywood decking and the finished floor?  Was this a first or second floor?   Was it over a properly constructed crawl space or a basement?  Were the floor boards pre-finished?  

   I recommend reading chapter 6 of "Understanding Wood" by R. Bruce Hoadley, Taunton Press.  It may seem to be on the expensive side ($40 US, $55 Canada) but it will save many an expensive project, and it is written by a woodworker, so the information is presented in a very useful arrangement.

   Plain sawn Hickory could easily shrink or expand 1/8 inch over 4 inches moving from 10% RH to 75% RH, but this swing is very unlikely in one week.

   It is because of expansion and contraction problems that plain-sawn flooring boards have typically been narrow (2 1/4 inch is typical in red oak), while radially-sawn or rift-sawn flooring boards are often wider.  Engineered flooring has changed these characteristics, permitting much wider finished surface veneers while offering new challenges to installers.

5. 
   lttljohn | Sep 21, 2010 10:45pm | #9

   Hickory Wood Floor Random Boards Splitting

   We just had a professional company install 3 1/4 planks for us in July of this year and within 2 weeks we noticed that some of the boards were splitting in the middle, on the ends, and running with the grain. As we started looking closer we noticed that the whole floor, 770 sf had splits popping up everywhere. It wasn't until we actually took post it strips and started marking out the areas on the floor that we realized how widespread the problem actually was. it is completely random but everywhere.

   We stored the wood in our house (still in the boxes) for 5 days to acclimate before the company came out to install the floors which took an additional three days to complete. Our sub floor is 3/4 OSB and we do have a crawl space that does have a moisture barrier and our floor joist are all insulated in the crawl space as well. The planks were nailed in the inside grove and run cross the floor joist, not with.

   We called the company that we purchased the floors from and they had the factory rep come out and take their Humidity readings and check my crawl space and said that they had never seen anything like this before, although this was almost 4 weeks ago and they still have not given us an answer as to how it will be resolved. 

   Our concern, is the inherent with Hickory (Which We Love, The Floors are otherwise Beautiful)? Should we be concerned if they take up the old floor and lay down a new one? What signs should we be looking? 

   Thanks

6. 
   gdblake | Sep 22, 2010 12:05am | #10

   One possible cause to the cracking

   The only cause for the cracks that I can think of is that the boards are cupping and are breaking (cracking) as a result of being walked on.  I would like to know if the boards are flat sawn or quarter saw (I'm betting on flat).  Any species of wood can become brittle if it is extremely dry.  Taking up moisture could easily caue them to cup and make them prone to breaking.

   Just a couple of thoughts.

   gdblake