Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Will another layer of ply fix a slight floor bounce?

Nurumkin's Avatar

Join Date: Aug 2008
Posts: 45

01-16-11, 03:29 PM   #1  
Will another layer of ply fix a slight floor bounce?

I posted about this issue in the flooring tile section and got the answer that I expected (that it would crack the tile). So I am coming to you subfloor experts to help me fix it.

I am remodeling an upstairs bathroom in an old farm house. It has 2x6 joists. I knew that there was a sag issue (the previous owners had a bathtub that was WAY to heavy for the floor). So I laminated some new 2x6's to the existing joists in that area. I got my subfloor down (3/4 ply) and noticed that there is a little bit of flex (maybe 1/8" tops when a 215 lb man stands on 1 foot and bounces up and down. I would really rather not pull up the entire floor and rerun my wiring to laminate new 2x6's to the joists. Can I just throw another layer of 3/4 ply on? Will this help stiffen up the floor or will it just add to my problem?

Sponsored Links
Tolyn Ironhand's Avatar
Group Moderator

Join Date: Nov 2007
Posts: 11,821

01-16-11, 03:35 PM   #2  
IMO - install a 1/2 hardie backer board that is put down with thinset and screws.

Electrical AC/DC and lighting Moderator
Professional Electrician, Handyman, all around swell guy!
40,000 people die in auto accidents per year in the US. We should ban cars.

chandler's Avatar
Banned. Rule And/Or Policy Violation

Join Date: Dec 2005
Posts: 39,968

01-16-11, 04:10 PM   #3  
I have a brother in law who does that with doctors. He goes to one and another until he gets the answer he likes. May not be right, but he likes it.
Your second layer, if you should choose to go that way, should not be screwed into the joists, but only into the original 3/4" subflooring. Before you lay it down, make sure the original subflooring is only screwed to the floor joists. Then use 1/4" backer set in thinset and screwed with proper backer screws.
This brings your floor up a little, but should be sturdier.

Search this Thread