Replacing carpet with "engineered" hardwood... what kind of glue?

[Dan Kelley]

First of all, hello to my fellow Beaver brothers and sisters!  My wife and I purchased our first class-A last Spring.  It's a '93 36' Contessa with the 300hp Cummins.  We're slowly-but-surely making it "ours" with updates and fixes.   The current project is eliminating the bedroom and living room carpet.  I'm replacing with engineered oak floor (plywood with real oak top), just like the original flooring in the kitchen.  I've put down the 3/8 plywood subfloor, and I'm just about ready to install the hardwood.  The original wood floor in the kitchen seems to be glued with a flexible / rubberized cement of some kind, perhaps to allow a bit of expansion and contraction.  Does anyone here have any experience in installing this type of floor, and if so, do you have a recommendation on mastic / glue? 
Thanks!
Dan

[Steve Huber Co-Admin]

Dan,

I installed laminate in our Contessa and engineered hardwood in our Marquis. Locktite construction adhesive worked fine for both installations.
Here's a link to the Marquis installations FYI. http://beaveramb.org/forum/index.php/topic,3725.msg28672.html#msg28672


As you 'll see, the coach had 2 sofas. After about 6 months, we decided that we wanted to replace the passenger side sofa with a recliner. I was able to remove the affected flooring and replace it without any major issues.
http://beaveramb.org/forum/index.php/topic,4368.msg32988.html#msg32988

Steve

 

[Dan Kelley]

Thanks Steve!
I looked at your threads above - great work!
Just a few of questions:  Does the loctite construction adhesive (PL Premium I assume?) maintain flexibility after curing?  How much did you use?  Did you run a zigzag bead on each piece of hardwood, or did you spread it onto the floor with a trowel?  Did you leave any expansion space around the edges?  I haven't noticed any gaps or buckling in our original kitchen floor of the same type, so it seems to be pretty stable with heat and humidity changes.  If I leave an expansion gap around the edge, then I'll need to use some shoe molding to cover the gap.  Otherwise I may just butt up to the edge and skip the molding.

Thanks again,
Dan

[Steve Huber Co-Admin]

Dan,
To answer your questions;
-Does the loctite construction adhesive (PL Premium I assume?) maintain flexibility after curing?
 I used PL. It does have a bit of flex post cure, but not much.

-How much did you use?  Did you run a zigzag bead on each piece of hardwood, or did you spread it onto the floor with a trowel?
Zig zag pattern on the pieces of flooring before snapping them in place. Did not use a trowel or apply to sub-floor itself

-Did you leave any expansion space around the edges?
I left about 1/8" gap around sides of floor. This was relatively easy as the floor in the front was covered by the center console and a gap in front of the driver's seat was not noticeable. Trim was already in place at the stairs so removing and replacing it after the new floor was laid to within a 1/8" covered that gap. The passenger side had carpeting on the lower wall so it hid the gap there. On the driver's side I ran the wood up to and slightly under the console left of the driver's chair. Remainder of that side was no problem as floor edge was hidden by slide elevated floor in salon. Rear of floor had gap as I used a transition piece to bridge to kitchen tile. One caution; when installing flooring on slide side, BE SURE to measure so flooring doesn't protrude past outer wall. (It's easy to do if you are not paying attention).
Since you apparently are going into kitchen, you'll probably have to use some 1/4 round or other toe kick to conceal the edges.
In my experience, the engineered wood does not snap together as easily as laminate. Be sure to get the installation tools that are available. I used the tapping and pull blocks. The spacer blocks are handy for ensuring the laid floor doesn't shift while you're working on it
https://harmonics-flooring.com/InformationResources/Installation
If you change your mind and go with laminate (not a good choice for kitchens due to moisture IMHO) use the same approach. Glue directly to floor.
In either case suggest you start on passenger side so you have a solid wall to work away from. Use spacers liberally on that side and front to ensure the expansion gap is maintained.
Good Luck! Feel free to call me if you have questions.
Steve

[Dan Kelley]

Excellent information, Steve!  One thing I don't have to worry about is the slide (don't have one).  I hope to get the floor down next week.  I'll holler back if I have any questions between now and then, otherwise I'll post some pics afterwards.

Thanks again,
Dan