1) Floors were installed in Nov-Dec 2000 by a professional installer. Covers approx 900sf.
2) A no-face underlament was used ( not sure of brand, just that it was called SU1 ).
3) Bostic Best was used to glue the flooring to the underlament.
4) A multi-purpose adhesive was used to glue the vinyl to the slab. Do not remember the brand, just that it had a stock number "356" in red lettering.
5) Appropriate leveling was done before the floor was laid. Not much was necessary, though.
6) Wood was in the house approx 2 weeks before laid.
7) Within 2 months, the floor started coming up from the slab. Hollow sections appeared; some as small as your hand and one about 30sf.
A 10sf section became like a small hill as it separated from the slab. After about 6-8 weeks, it settled back down to "sea level" and has remained there for a month or so. This section is in an open room.
The 30sf section was the worst; it severely peaked ( like a church steeple you make with your hands when you were a kid ) about 3-4" off the slab. This is in a hallway.
8) The installer returned to inject glue in a couple places, but it's coming up again.
9) We finally pulled up the 30sf section to check for moisture underneath. There was nothing obviously wrong. The wood was stuck solid to the vinyl.
10) A plumber was brought in to check the house for plumbing leaks, but none was found.
11) An engineer did a foundation review and found no significant structural problems. He did a moisture test using some gizmo placed against the wood in several spots throughout the flooring. He said the measurement was 10%. I do not believe he checked the moisture of the slab itself.
WHAT NEXT? We are at a loss as to what to do. Do not want to replace the 30sf section without knowing the root cause of the problem. Plus, still have several spots throughout the rest of the floor that remain unbonded.
I have read the postings on this BB and don't see anything like this -- or, at least, nothing as severe.
Any and all advice welcomed!