I would like to to put down a DRIcore subfloor over my on grade concrete slab floor and then install engineered hardwood flooring on top of it. Should I staple the flooring to the DRIcore and if so should the DRIcore itself be fastened to the concrete slab? I have heard conflicting opinions on whether or not the DRIcore should be fastened to the concrete. Or would a floating floor be recommended over stapling with the DRIcore? I have often heard that floating floors are inferior to stapled down flooring in terms of sound and feel when walking on them, that they sound 'hollow' or creaky. I do not want to glue my floor down. Any recommendations?
I have placed Dricore or its equivalent on 2 different jobs. Both are holding up fine, neither felt hollow or creaky. One was in a basement slab, the other was placed on a slab on grade such as yours. The only difference is one had 4" to 10" wide plank flooring from recovered barn wood, the other 2 1/4" strip.
While the subfloor was being laid, I glued the edges of all the pieces before placing. even though it is not required. Also the perimeter had a gap to the wall of at least 1/2". It is laid as a floating floor. I really don't see any problem stapling down your engineered floor to that. When the strip floor went down, the staples where checked for length so they did not go all the way through and pierce the plastic matting.