Hi all,

I have been building a home in Texas, it is a slab on grade foundation. I have a question re flooring. 

I will be using engineered hardwood for flooring in several areas. I have prepared the concrete with epoxy for moisture control (Ardex MC Rapide) and self leveler (Ardex v1200) to create a suitably flat and level substrate. I would like to match my adjoining floor thicknesses – this gives me 1 1/4″ to work with. This gives me 2 options, as I see. 

1. Glue down 1/2″ baltic birch plywood, use 5/8″ engineered hardwood flooring anchored using 1 1/4″ metal cleats. The main advantage of this option would be the possibility of removing the hardwood.

2. Glue down 3/8″ baltic birch plywood, use 3/4″  engineered hardwood anchored with glue. The main advantage of this approach would be the additional time the flooring could be refinished. 

Which option do you suggest is preferred? My main other questions are, is 3/8″ BB plywood too thin, I am only using it to match thickness? NWFA states 3/4″ in all their guidelines, but I dont see how thats important over concrete, and I am using BB which is much more dimensionally stable than OSB.  Last question, how much thickness does elastomeric glue add, I am thinking about 1/8″ when applied using 3/16 v-notch trowel? 

Thank you all.