Questions:

1.) Is it suggested that one apply a skim coat product (e.g., Mapei Ultra Skim Coat) to a concrete slab to ensure that no carpet glue adhesive and/or other contaminants do not react with the floor adhesive? In my case the adhesive was brushed off (but a shiny, yellowish stain remains on the slab wherever the carpet glue was applied)

2.) If I were to apply the skim coat product, is this something that I must apply over the entire concrete slab, or just along the carpet glue-stained areas?

3.) Is the thickness of the applied skim coat negligible (assuming you spread it as thin as humanly possible)? I would not want to have to undercut the hearth and door frames again.

Thanks!

This may help

http://www.mapei.it/Referenze/Multimedi ... _TD_EA.pdf

Thanks! I'm assuming that when they say "featheredge", they mean the skim coat has almost negligible thickness over the concrete slab.

Your assuming right