How to level subfloor for laminate install?


  #1  
Old 11-12-07, 10:44 AM
G
Member
Thread Starter
Join Date: Mar 2007
Location: USA
Posts: 149
Upvotes: 0
Received 0 Upvotes on 0 Posts
How to level subfloor for laminate install?

So I have a plywood subfloor in a 20 year old house. I have 3 rooms.

The first room, I just assumed the floor was level. After installation, I realized that it was not, and there is now a "bouncy" spot in the floor where it gives.

The second room, I used an 8' 2x4 to mark all the low spots. I tried to use roofing paper to fill these spots, but did not adjust properly for height. Still bouncy. Plus I think the 2x4 wasn't exactly straight to begin with.

The 3rd room, I connected a full row of boards together as perfectly as I could. I laid this down sideways along the floor and used roofing stacked up to get a feel for how high it needed to be raised. I moved along every 6" doing this and covered the whole floor. In some cases, the roofing paper was 16 sheets thick. I then checked it after the paper with the boards.

The result? The floor still gives!! The first two rooms were pretty minimal, but this last one is somewhat noticeable.

I am now in the living room. I needed to raise it about 1/8-1/4 an inch with a luan underlayment to get it to the same height as the dining room (which used to have linoleum). I thought that adding the luan would fix the low spots. It didn't.

What am I doing wrong?

The connected boards is the flattest thing I can find. I tried searching for a 10' alumininum screed as suggested earlier, but they are unavailable in my area.

Please help!

Does 16 layer of roofing felt seem like a lot for a 20 year old house to be sagging?
Is it strange that there seems to be little to no regularity to the dips?
The floor is the 1st floor of a home over a fully finished basement and garage if that helps.
 
  #2  
Old 11-13-07, 07:17 AM
G
Member
Thread Starter
Join Date: Mar 2007
Location: USA
Posts: 149
Upvotes: 0
Received 0 Upvotes on 0 Posts
So I haven't heard anything yet, but was wondering if I could use additional layers of foam underlyament to help level out the floor.

The roofing paper doesnt seem to be working very well for me. My laminate already has foam attached to the back, but would more cause a problem?
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: