I have a question about installing hardwood flooring. I purchased Brazilian real hardwood flooring, 3/4 inch thick.
I wanted to installed the flooring in my condo. The condo is located on the 12th floor with a concrete base.
I spoken to many floor installers and they all have different ways of installations. Some recommend a glue down,
which consist of applying glue to the concrete, laying down either cork or rubber pad ( for sound installation )
and then glue down the hardwood. This procedure can be very expensive. The other way is a nail down, which
you level the floor then glue down a rubber pad, then glue down the plywood to the pad, and then nail the hardwood
flooring on top of the plywood. The last way someone suggested is to level the floor then lay down plywood and nail
down the hardwood flooring, (would there be a sound barrier) doing it this way. Could you tell me which is best and
the most cost effective way. I do have to have some sort of noise barrier because it is in a condo and the strata requires this.
Is there a concern with moister since the suite is on the 12 th floor. I live in Vancouver B.C.

Thanks

IMHO, that 3/4" solid isn't the best choice. I think you would be better off going with a floating floor. There are a few reasons. First, that "concrete" you speak of for your substrate/subfloor most likely is not concrete but a type of product called gypecrete. This is a poured on, lightweight cementious underlayment used in multi-storied buildings for fire proofing mostly. Underneath the gypecrete, you would have either a wood or corrugated steel subfloor. One cannot glue or nail to gypecrete effectively. There are products that aid in allowing one to glue to gypecrete from my understanding. But still, the fact remains, that it isn't a good substrate to attach wood to. Therefore, going over it with a lightweight, low profile floating floor is ideal. You can use either cork or the Floor Muffler for sound absorption. Best to check with the Homeowners/Condo Assoc. first to make sure that whatever product you select will qualify as acceptable concerning noise and fire. There are many fine floating floors available in Brazilian Cherry. Kahrs, Sunfloors, Tarkett, Award, Bruce, etc. all make a floating longstrip style, which is fairly easy to install. This would be my recommendation. Installing a 3/4" in your case, would be a poor choice, IMO.

¾" is not recommended to place over concrete, period! They say you can glue down ¾, but there are very specific requirements, and then your at the mercy of the milling and bowing of the boards, along with dew point concerns and the cooler concrete.







Yes, seldom are two installers on the same page. There are many ways to skin a cat, but what really matters is your buildings condo associations, noise transfer requirements. There is a lot more to it, then just placing cork under the installation, to meet sound canceling requirements.









Rarely will gluing down, like suggested, will meet today's sound transfer requirements, for condo associations. and then you have a stout ¾ working against you. Remember ¾ is not suppose to be glued down, ask the manufacture of the wood. Also, solid wood is not recommended over concrete.










This still may not meet sound deadening requirements, as your still fastening the system to the concrete, which will transfer noise to the condo below.






No, no sound barrier is used. That way is commonly done on ground floor installations, where you don't have neighbors downstairs. Being up on the 12th floor, the concrete is most likely some type of lightweight pan poured cement. A fastener is not going to hold into light weight cement. Which reminds me, gluing down to light weight concrete, is a failure waiting to happen.







It my not be cost effective, but you need to isolate the flooring system from the substrate, so noise transfer is greatly reduced.

Plastic, poly moisture barrier, no less than 6-mil, overlapped 6-8 inches and taped with clear packing tape, which has a high perm rating.

Roll out your cork and cut to fit. leave it loose laying.

Take 4x8 sheets of ¾" BC plywood and rip them into 16 inches x 8 feet planks.

Lay those planks you just made, opposite the direction of the direction the finished flooring will be, staggering them so the ends are random and no closer than 10"

You will need a strip of cork at the perimeter of the room all the way around for both plywood subfloor and the finished floor. This keeps the flooring from transferring noise into the wall structure, which is attached to the framing, which transfers noise to the other condos.

Lay the flooring, with the cork expansion gap.

When you install wall trim moldings, use a spacer to keep them up slightly off the flooring, because again, attaching it tight down to the flooring transfers noise into the wall.







Yes, most all condos have a sound transfer requirement. Some will not allow hard surface flooring in a condo, that covers more then a small % of the unit. You can't have hard surface(wood) throughout. These rules are strictly enforced! They can sue you and then kick you out, if you don't spend more money to abide to the requirements, if it is done wrong.
It sounds like to me, none of the contractors you have interviewed, have any experience in condos and noise transfer, especially what is required to successfully meet those strict noise transfer requirements.








Moisture is always a concern with concrete. It does not matter if it is below grade, on grade, or 100th floor of a high rise building. Concrete will always have vapor emission concerns, along with dew point concerns.
Concrete vapors are dynamic and not static. They change all the time, and solid wood will freak out when moisture gain or loss is experienced. This includes moisture in the air, called humidity.