installing hardwood not perpendicular to floor joists…what are the implications?

Issue by Bieliquist: putting in hardwood not perpendicular to floor joists…what are the implications?
I have just set up hardwood floors and know that they are to be installed perpendicular to the hardwood flooring joists. On the 1st stage, the installer did it appropriately and they ended up put in perpendicular. I cherished the seem so considerably that I also had him install hardwood in our grasp bed room upstairs, and when I went to check out on him midway by means of the day, I discovered he was not heading perpendicual, but paralel as he said it does not HAVE to be perpendicular, but typically will be mounted the longest width of the area. Effectively, even though I appreciated his advice concerning estetics, it stressed me out much too significantly (from every thing else I was looking at), and I had him rip it all out (he was about one/2 way in a thirteen x 15 room) and re-start off once more the appropriate way (perpendicular). Though he was a minor upset, I feel he understood I was correct and the “estetics” is not what is critical to me, but the truth to I will not have difficulties down to street is far a lot more crucial. Nevertheless, what I was pondering is what is the genuine purpose for installing them perpendicular? What would be the long phrase impact if I had allow him carry on heading paralell with the joists? Of every little thing I have study, this question genuinely has not been answered (the “why”).

Also, what would take place if the hardwood is not given satisfactory time to aclimatize to the place? The hardwood boxes contain recommendations adising 48 hrs, which I in fact gave 72 hours + … but what would have happened if we had not permit it aclimatize?

Many thanks for all your suggestions!!

Best response:

Solution by Rob E
Hello, I was in the ground covering organization for 10 years though did not install true hardwood floors. If you subfloor is sound I see no explanation why you could not install the hardwood any route you desire. I would picture laminate floors would act the same way. I had by no means heard of having to install a certain course. As far as allowing the hardwood flooring acclimate unless of course the hardwood flooring was warehoused in a very cold local weather odds are you would have been fine.

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  1. sensible_man says:

    The reason for installing perpendicular to the joists is strength. You would have support every 16″. If your underlayment is sufficient though, it would not make a difference since the joists would be supporting the underlayment. Your installer is correct that most flooring is installed along the longest wall. Not acclimating the flooring can result in the wood expanding or contracting after installation due to a big difference in the room temperature and the temperature of the flooring. Differences in humidity could also cause this problem.

  2. Lady K says:

    The hardwood must be perpendicular to the joists for stability. Otherwise, the floor may sag and it could be potentially dangerous over time. You let hardwood acclimate to your home’s environment so it shrinks. If you put it down without doing this, once the floor is laid, it could shrink and you will have gaps.

  3. travelingsupervisor says:

    Installing wood flooring perpendicular to joists helps avoid squeaks by having a stronger floor as the new flooring is “bridging” the joists rather than settling into the “valleys” between the joists or riding the “crowns” of the joists. Granted, the valleys and crowns are not often a factor in newer homes with adequate sub flooring materials. Wood flooring can also be installed at a diagonal to the joists. As for installing the wood flooring parallel to the longest wall,,, that is generally not true,,, mostly it is installed parallel with either the front or rear exterior wall.

    Acclimation is important to help avoid cracks opening where the individual floor boards butt each other. This really becomes important when there is a big humidity difference between where the material was stored and where it will be installed. The temperature between the two locations is something of a factor when you are talking about extreme differences.

  4. ANF says:

    You were quite correct as the perpendicular configuration would give better strength to the floor.
    If you do not let the timber acclimatise but put it straight down it would change in length within a day or so due to the drying out and/or the differences in temperature from where it has been stored. If your house is warmer than the storage area each piece would increase in size according to the coefficient of expansion of timber. If this occurred when the floor was finished then the timber would strain and warp if there was not a point to take up the expansion.

  5. curious george says:

    The impact of installing the hardwood floor parallel with the joists is that the strength of you floor comes mostly from the sub floor( the tounge and groove of the flooring provides no additional support). If your bedroom was carpeted before, your were relying on the subfloor then (and maybe a little from the underlayment, depending on what it was). Laying the hardwood floor perpendicular to the joists adds strength to the floor between the joists.
    If the flooring is not acclimatized, it can warp after installation as the wood’s moisture content and temperature change from what it was at installation

  6. Ron G says:

    You were correct in making him rip it up. He was just trying to install it a little quicker. The boards should always be installed perpendicular to the underlying joists to give it the best overall appearance and strength. One of the reasons to do this is they next time you want to sand and refinish the boards that you have down. If run parallel they will ‘sag’ with load and age and you may end up sanding through the board in worst case. In the perpendicular way there is less ‘sag’ with normal use and the boards are more likely to take the refinish sanding without any problems. Hope this helps and do not have that installer back.

  7. Irv S says:

    It is not necessary to install that flooring ‘perpendicular’ provided that
    the sub-floor is adequate.
    It is better to do so if you feel that the sub-floor might be a bit soft,
    but not by much even then.

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