I have a running post on the General Forum and now post here to get ideas for fixing a pre-installation problem...

I am 9 days out from my Professional Installation. Knowing I have had a problem for years, I decided last week that I needed to investigate and expected a Horror Show. Instead, I found that I just have some shoddy workmanship on the construction of my 25 year old home.

Running down a hallway (perpendicular to the floor joists), I have a span of about four joists where the floor dips. I have one joist where the delta between the joists on either side is nearly 1/2". The remaining overall run is very gradual but noticeable under foot.

So, as posted in the other message, I am tearing out all the carpeting and the 1/2" particle board underlayment and my pro is laying down 1/2" plywood before the floor (and I told them to use 15# felt instead of that MYSTERY PAPER ). Recommendations for "filling the big dip" so that the underlayment is as tight and level as possible? I was thinking possibly a 16" wide 1/2" plywood where the leading edges are planed gradually to an 1/8" and screwed down the center to the joist and on each edge across the subfloor???? or possibly just a 4" wide 1/2" screwed to the joist and 4" of 1/4" ply on each side??

This neophyte is looking for ideas. I am now going back to the links on these pages for installation gotchas. Don't think layering felt would be the best for this issue.

Thanks.
AGE

OK, BEFORE laying the 1/2" ply, fill the "dip" with cheap 3 tab roofing shingles; you know, the composition shingles. They're about 1/8" think and work great for layering up. DON"T USE any fixall or crap like that. Once you have the shingles filling the "dip" fairly well, lay the 1/2" over that and your home free!

Shingles are life-savers. That rolled roofing is geat too.

Cool. The Pro Sales and Site Inspection "professional" is coming to see my "issue" this afternoon. I will listen to what he has to say and then see if he can come to a very simple solution such as this. I can get tabs anywhere in my area (lots of home construction).

Great idea. Thanks.

I have another question that I am posting regarding installation ideas.
AGE

There is no easy solution in leveling a sub-floor in homes that have moved due to soil compaction and settling. The suggestions offered on this forum are ways to "fake it" within reason. If the floor looks flat/level by use of shingles, roofing felt........ you won the battle, temporarily. Please remember that the home may settle more and again become un-level. In older homes, the soil under the home is often lower in elevation than surrounding soils which means water under the house and additional soil movement.
Have fun.
Ray

My project is just about complete. The flooring is down, my work (fixing a railing base and support) should be in the final coat and finish tonight, and all the old baseboard is back in place (until we replace all the doors in the years to come).

So, they built up the "dip" with felt and spare spline. With the 1/2" ply across the top, it seemed incredibly stable and was nearly perfectly level. With the 3/4" flooring atop that, it is unnoticable.

Thanks to all for your advise. We are just about complete.

AGE