Expert: Bruce E. Johnson - 5/22/2010

Question
QUESTION: Hello,

I have a 2 story house with a pier and beam foundation. We have laminate wood flooring which is bulging in places. An engineer recommended we jack and shim the piers to level out the house. This did not help.Someone said that we probably have several crowned joists throughout the house. Any ideas on how to fix this or how much it would cost if we needed to hire someone to make these repairs.

Thanks

Caryn

ANSWER: Hi caryn, are you sure the bulging is caused by the floor system?  Sometimes if laminate flooring is installed improperly without room to expand it will bulge on its own.  Laminate flooring products expand and contract and need to have at least a 1/2" gap along the walls and should "float" on the subfloor without any attachment or solid connection to the subfloor like glue or paste or nails unless specified to do so by the manufacturer.  If your laminate is installed properly according to manufacturer's specifications and it really is crowned joists that are causing your problems then you can alleviate the crowns in the joists using the following method:  1. locate the joist that is overcrowned  2.  make a vertical saw cut up the joist using a skil saw or a sawzall (this should relieve the pressure of the crown and allow the joist to flatten out) 3. Once you are satisfied with the flatness of the floor. On each side of the cut joist you glue (using a heavy duty Liquid Nail) and screw (using a properly sized coated deck screw) a 4 foot piece of 3/4" plywood ripped to the size of the joist and centered on your cut to reinforce the joist.  In lieu of the plywood you can use a kiln dried 4' piece of similar sized joist material and glue and screw that to the joist for reinforcement.  Try to let the glue dry for at least 8 hours before allowing a lot of foot traffic on the newly modified joists. I hope this information helps, please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com

---------- FOLLOW-UP ----------

QUESTION: Hello,

Thanks for the quick response. We are certain that it is the floors because they are humped in other rooms that dont have wood laminate flooring. Would it be easier to determine which joist are crowned by
removing the sub flooring, since we are going to be removing all existing wood laminate, carpet and vinyl? Or should it be done from underneath the house thru the 3 ft crawl space.
If I were to hire someone like you that has experience with these repairs what price range would I be looking at? The areas in question cover about 1700 sq ft.

Thanks

Caryn

Answer
Hi again Caryn, whether or not to remove the subfloor kind of depends on how easy it is to take up.  Many homes have the sub-floor glued and nailed to the joist so it won't be easy to rip up and will probably need to be replaced with new.  Also if the full sheet runs under a wall or partition you will have to cut it back to the center of a visible joist or it will be a pain. If you have three feet of crawl space any young handyman type can get under there with some battery powered tools and some precut repair boards and take care of business from below.  As far as costs go?  Figure at least 100 dollars an hour for a qualified contractor to do the work.  This would probably take a good three hours to determine the problem joists and drive a large identifiable nail next to the bad ones.  Then they would need to locate them below and see what the actual working conditions are, whether there are any pipes or plumbing in the area, that type of thing.  Once this is done then figure at least an hour per joist for the repair, and a couple hours of going to the lumber yard and getting the materials, and maybe a hundred to a hundred and fifty dollars for the material.  So if you have five joists that need repairing you would be looking at 3+5+2 or ten hours labor 1000 dollars, and 150 materials..1250-1500 dollars depending on the going rate for decent carpenters in your area. But who knows? The way the economy is right now you are in a better bargaining position than ever before to get a decent price.  If you have to tear up sub flooring and go that route then there may be more money involved for labor and materials. I hope this information helps, please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com