Hi all I just had a contractor level my apartment bedroom floor in preparation for me putting in laminate flooring. I'm on the third floor, and the floor base is concrete. The contractor came the other day with bags of LevelQuik RS underlayment. I watched him work for a while then left him to it and went out. When I came back I found the floor wasn't flat. There are noticeable differences in elevation between the areas where the different bucketfuls were emptied. I tried laying some flooring down (without underlay) and there are noticeable sagging spots. I have watched some videos of people applying this stuff and they all use trowels or other tools to move the compound around. This contractor did not, he just poured the stuff out and let it find its own level. So I'm not sure what to think. Is it reasonable to expect a totally flat floor? Did my contractor apply the stuff correctly? It gets better: I also noticed last night that there are hairline cracks in the underlayment. thanks in advance, David (total and utter DIY newbie)

Long time lurker on these forums but first time poster. I have learned alot from these forums so first off thank all of you who post. Backstory: Im getting first condo/place which i will own. The previous owners did a terrible job with the floors. The 2nd floor, which has the kitchen transition to living room, is entirely tiled with hideous terra cotta style tiles. I am going to re tile the kitchen and put laminate floor on living room. Im looking for suggestions on height differential or any safety comments. This is my first LARGE scale DIY job. Here is my plan. Remove everything down to subfloor for kitchen and living room. Start fresh. In the Kitchen I would thinset 1/8 (.125), cement board 1/4 (.250), thinset (1/8 1.25), tile 3/8 (.375) *That is height of tile per package Total Height .875 In Living Room Attach 3/8 (.375) plywood to existing subfloor to make for height and make more secure. Laminate floor 10 mm + 1mm attached pad (.433). Total Height .808 .875 - .808 = .67 Tile to Laminate floor differential. To counter that would use a reducer and or T molding if would work. I am concerned about my procedures and the height difference. I could replace the 3/8 plywood with 1/4 but that just leaves bigger gap. Any comments would be appreciated.