I have 2600 sq/ft (main floor, basement)in which I want to heat using radiant heat. I know the two ways of installing are embedding in light weight cement,or using alluminum strips (either between floor joists,or directly on the sub-floor).Do you really feel the difference between the two? Also, I want to install a hardwood floor. Will this heating cause gaps in the flooring (besides the regular expansion/contraction that will occur)?