30 or 15 or both

[highup]

I've always leveled floors for Laminate or LVP with filler.
I have a job about ready to start with a Mohawk LVP. It's an upstairs converted to a second rental.
It's going over an old fir floor so Ardex doesn't seem like the best option.
When layering felt I'd assume #15 would be the best option?

 

[C.J.]

I've always leveled floors for Laminate or LVP with filler.
I have a job about ready to start with a Mohawk LVP. It's an upstairs converted to a second rental.
It's going over an old fir floor so Ardex doesn't seem like the best option.
When layering felt I'd assume #15 would be the best option?

The difference between 15# and 30# is thickness. 30# is 1/32” thick. You’re allowed up to 6 layers. 6 layers at 1/32” gives you 3/16”. I suppose if you need more than that then you’re getting into using Masonite or 1/4” ply for more depth.

 

[highup]

When walking over a leveled area, does it ever make any Snap Crackle, Pop noises with multiple layers?
...and does off gassing deteriorate the foam cushion over time?

 

[C.J.]

I haven’t had any problems with roofing felt making noise or stinking up a house. Lay it down, staple it and do it again. I do go back and hit the staples themselves with a hammer just to make sure they aren’t going to cause you a problem down the road by being proud.

As far as roofing felt deteriorating the foam cushion, I couldn’t tell ya. I only ever ran across deteriorating foam one time. Somebody drilled a hole and squirted something underneath the floor to try and fill a void. Didn’t work. Whatever it was never hardened. It had a real bad chemical smell when I opened up the floor. Still gooey and it melted all the foam around it.

 

[highup]

Thank you sir. I really appreciate your input. Overthinking has always been my best trait. If you can build something in a day, I can come pretty close in a week. 😁