I see that others often put down a foam underlayment first, the kind that comes in rolls. Our new flooring is tongue-and-groove engineered wood and it'll be going on plywood that's been painted with a waterproof barrier (a building requirement). The plywood is on subfloor and wood joists. I see a 2 mil foam product that has an adhesive strip to stick down. Something like that? Can anyone recommend a product they've used for a similar application? I'd like to keep it thin if possible. The manufacturer has been pretty unhelpful in specifying something.

Hi, Replacing sub-floors and walls and now rebuilding an entire interior load-bearing wall that has a header spanning a 4-foot wide hallway. The old header was simply two 2x12's on one jack stud each end. One end is in an exterior wall. Other headers I've replaced have been duplicates of what was there, two 2x10's (typically) with a 2x4 (bottom plate?) on the bottom. This 2x12 had no 2x4 bottom plate. Questions: For each header, I exactly replicated what was, just the 2x[whatever] siamesed together, centered over the 2x4 bottom plate, but now I see that it's common to put 1/2 plywood between to build them out flush to the 2x4. It wasn't that way, is that necessary? I want to be sure I'm to code. From what I read (??) of the ICC code to determine header span material sizes, [url=http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015%20IRC%20HTML/Chapter%206.html]Codes and Standards | ICC publicACCESS[/url] it says "building width is measured perpendicular to the ridge." The ridge is parallel to the front and back of the house. For my 2x12 header, the load bearing wall containing it is perpendicular, so am I going by the width of the two rooms that rest on the wall? BTW - can't ask the inspector - he's not happy we're past the permit expiration, so I don't want to rock the boat. :eek: Waiting to cut lumber... Thanks guys.