Installing Solid Hardwood On Slab

 
Thread Tools Search this Thread Display Modes
Old 05-24-2013, 04:20 PM   #1
Pro
 
Eaglei's Avatar
 
Trade: carpenter & Masonry
Join Date: Jul 2012
Location: Staten Island N.Y.
Posts: 837
Rewards Points: 1,028

Installing Solid Hardwood On Slab


After having failed the first time I want to make sure it gets done right this time . I'm installing a 1200 sq. ft. dance floor for a dance studio . The problem that I had the first time is the moisture from the concrete slab on grade eventually made it's way through to the solid oak flooring . I first noticed the floor start to cup after a few months and then start to buckle after 6 months . Time was a big issue and I could'nt follow all the proper procedures such as proper acclimation of the wood . I used a 6 ml vapor barrier on top of the concrete and 3/4'' ply on top of the vapor barrier . My biggest concern now is what to use on top of the concrete to seal it from the moisture . I tested the concrete with a moisture meter and it shows on average 12% moisture . I also tested the plywood and oak flooring , ply was 10% and oak was between 7-10% moisture .

The problem with the moisture barriers is that when fasteners are used it no longer is a moisture barrier . The plywood is used to help soften the dance floor and when fastening the ply to the concrete it penetrates the moisture barrier . I'm thinking to put a moisture barrier above and below the plywood . Thoughts on that ? Maybe 6ml on top of concrete and M.V.P. on top of plywood . Can M.V.P. be used to install the solid oak floor on top of plywood without fasteners ? I have no experience with M.V.P. or similar product . I also know I have a moisture problem with the concrete slab from previous flooding so i'm I going to fail again ? Should I look into using engineered flooring ? Theres a lot to think about and I know some off you floor guys could lead me in the right direction . Thanks Ken .
Eaglei is offline  

Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ContractorTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

   

Advertisement

 

Old 05-24-2013, 04:56 PM   #2
Remodeler
 
TAHomeRepairs's Avatar
 
Trade: Residential Contractor
Join Date: Jun 2012
Location: Central Florida
Posts: 848
Rewards Points: 560

Re: Installing Solid Hardwood On Slab


Isn't the recommendation two layers of plywood and I think two layers of 30# felt, or something like that, i'm sure someone will be along to correct me, or be a little more specific.

Advertisement

TAHomeRepairs is offline  
Old 05-24-2013, 05:07 PM   #3
Fire up the BBQ
 
griz's Avatar
 
Trade: GC
Join Date: Nov 2009
Location: CA
Posts: 14,059
Rewards Points: 5,394

Re: Installing Solid Hardwood On Slab


Not sure if I posted this in your other thread on this topic.

Look at this product:

http://www.moxie-intl.com/existingconstruction.htm

Give them a call & explain your problem. They are knowledgeable & very helpful folks. I've used this product several times with excellent results.

6 mil is a vapor rertarder not a vapor barrier.
Have you done a RH Test on the slab?
__________________
SOME JOBS JUST AREN'T WORTH DOING:
griz is offline  
The Following 2 Users Say Thank You to griz For This Useful Post:
Eaglei (05-24-2013), PrecisionFloors (05-24-2013)
Old 05-24-2013, 07:57 PM   #4
Paul
 
PrecisionFloors's Avatar
 
Trade: Hard Surface Flooring
Join Date: Jan 2006
Location: South Florida
Posts: 3,630
Rewards Points: 554

Re: Installing Solid Hardwood On Slab


No moisture barrier sandwich! Ardex has some excellent moisture mitigation products. I would go that route with two layers of plywood ran perpendicular to one another, only fastened to each other - not the slab. A floating subfloor if you will.
__________________
Precision Floors
(772) 237-9900
Tile, Hardwood, Laminate, and Resilient
Installation, Sales & Repair - "We do it right the FIRST time"
PrecisionFloors is online now  
The Following User Says Thank You to PrecisionFloors For This Useful Post:
Eaglei (05-25-2013)
Old 05-24-2013, 08:14 PM   #5
Pro
 
fjn's Avatar
 
Trade: mason
Join Date: Aug 2011
Posts: 2,194
Rewards Points: 2,748

Re: Installing Solid Hardwood On Slab


Never used this stuff,may have some potential.

http://extremehowto.com/installing-a-floating-subfloor/
fjn is offline  
The Following User Says Thank You to fjn For This Useful Post:
Eaglei (05-25-2013)
Old 05-24-2013, 08:50 PM   #6
Pro
 
BCConstruction's Avatar
 
Trade: Construction
Join Date: Jun 2009
Location: Roanoke, VA
Posts: 12,985
Rewards Points: 1,620

Re: Installing Solid Hardwood On Slab


I'm no expert on hardwood floors as most of the times I see them installed it was on block and beam floors but the couple of times I see them installed on a slab on grade they used a foam board glued to the concrete with the seams taped and then plywood glued to the foam board with the hardwood glued or stapled to the plywood. No idea how it held up long term but I ain't ever seem anyone over here ever do them like this. May be worth looking into.
__________________
www.bcconstructionllc.com
BCConstruction is offline  
The Following User Says Thank You to BCConstruction For This Useful Post:
Eaglei (05-25-2013)
Old 05-24-2013, 11:24 PM   #7
Pro
 
Tom M's Avatar
 
Trade: GC/ Interior & Exterior Remodeling
Join Date: Jan 2007
Location: Bergen County, NJ
Posts: 4,350
Rewards Points: 3,890

Re: Installing Solid Hardwood On Slab


So to add to the concern are we using SS fasteners with the base layer of ply treated? I dont like the idea of punching into the slab with anchors either, defeats the vapor barrier.
Tom M is offline  
Old 05-25-2013, 12:19 AM   #8
Pro
 
ccoffer's Avatar
 
Join Date: Jan 2005
Posts: 678
Rewards Points: 816

Re: Installing Solid Hardwood On Slab


My fave method is to just plop 3/4 inch Advantech down over 10 mil polyethylene. If you're paranoid about panelization, just take some metal flashing and sister everything together.

It's great. Super fast. Super stable.

Last edited by ccoffer; 05-25-2013 at 12:22 AM. Reason: more
ccoffer is offline  
Old 05-25-2013, 12:21 AM   #9
Pro
 
ccoffer's Avatar
 
Join Date: Jan 2005
Posts: 678
Rewards Points: 816

Re: Installing Solid Hardwood On Slab


Attaching plywood to concrete is dumb. A waste.
ccoffer is offline  
Old 05-25-2013, 12:12 PM   #10
Pro
 
Eaglei's Avatar
 
Trade: carpenter & Masonry
Join Date: Jul 2012
Location: Staten Island N.Y.
Posts: 837
Rewards Points: 1,028

Re: Installing Solid Hardwood On Slab


Quote:
Originally Posted by Tom M View Post
So to add to the concern are we using SS fasteners with the base layer of ply treated? I dont like the idea of punching into the slab with anchors either, defeats the vapor barrier.
I used the hilti zamak pin bolts , drill first then drive them in with a hammer . I'm not sure what metal there made of but there made for concrete and very expensive considering the amount I needed .
Eaglei is offline  
Old 05-25-2013, 01:42 PM   #11
Pro
 
Tom M's Avatar
 
Trade: GC/ Interior & Exterior Remodeling
Join Date: Jan 2007
Location: Bergen County, NJ
Posts: 4,350
Rewards Points: 3,890

Re: Installing Solid Hardwood On Slab


My concern was with treated plywood and ground contact normal fasters will corode.

Advertisement

Tom M is offline  


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Paint or Solid color stain? kenmorgen Painting & Finish Work 8 04-27-2013 01:03 AM
Installing solid hardwood floors over particleboard dsmoser Flooring 35 07-13-2011 12:01 PM
5 Best Hardwood Floor Tips And Save Money Too! Benoakley Flooring 6 08-17-2009 01:49 PM
Installing Hardwood. tips and what to look for....in a finishing contractor? J-Peffer Flooring 3 03-24-2009 09:58 AM
How to Install Solid Hardwood Flooring on Concrete Foundation gilamherst Flooring 13 02-05-2005 07:02 PM

Join Now... It's Fast and FREE!

I am a professional contractor
I am a DIY Homeowner
Drywall Talk is for
PROFESSIONAL CONTRACTORS ONLY!

At DrywallTalk.com we cater exlusivly to professional contractors who make their living as a contractor. Knowing that many homeowners and DIYers are looking for a community to call home, we've created www.DIYChatroom.com DIY Chatroom is full of helpful advices and perfect for DIY homeowners.

Redirecing in 10 seconds
No Thanks
terms of service

Already Have an Account?