vapor/moisture barrier necessary?

eis61374

Another newbie question:
Being that my condo is on the 3rd floor in an apartment building is it necessary to have any sort of vapor/moisture barrier installed over the concrete slab subfloor before I put down Advantech underlayment for a 5/8" strand woven bamboo floor.
There is an 1/8" layer of "insulayment underlayment" on top of the concrete but I don't know if that is all that is necessary.
Thanks in advance!

Gevans17

According to their website: "Hardwood floors: May be applied directly over 23/32" AdvanTech flooring panels"

However, they also say to follow the installation recommendations of the flooring manufacturer. How do you plan to install the flooring?

eis61374

Hi Gevans17, thanks for taking the time to offer your help.
I'm planning on laying the Advantech over the insulayment that is already down & then nailing/stapling the Bamboo to the Advantech. The insulayment doesn't appear to be a moisture/vapor barrier, just a noise dampener, so I'm worried about moisture coming up from the concrete subfloor, going thru the insulayment & & either causing mold or warping the bamboo.
I know the concrete subfloor is above grade but I can't find information online about whether above grade concrete subflooring needs a vapor/moisture barrier or not.
Again, thanks for any help you can offer.

Gevans17

might want to contact the manufacturer of your hardwood flooring for their specific instructions. Most manufacturers tell you to check the moisture content of the slab with a moistrue meteer pprior to installation. I floated my floor over concrete slab on a Floormuffler underlayment. Floormuffler acts as both sound and moisture barrier. Costs approx 60 cents per sq ft.

eis61374

Thanks again Gevans17. I will check with the floor manufacturer. I have no idea if moisture tests were even done on the concrete as the construction company who built the building is ridiculously inept & its looking like a class-action lawsuit may be down the road. Fun!
Thanks again.