Solid Hardwood, Engineered and Laminate Flooring - Subfloor Leveling

The wife and I removed the carpet from our family room only to find that the floor is quite uneven and is in relatively bad shape. The biggest problem is a large bulge that runs all the way across the floor and is centered roughly over the main I-beam house support.

Since we were planning to lay laminated flooring, the 1/4 inch bulge is unacceptable. The plan is to place a plywood layment over the existing subflooring, but, obviously, the new layment will want to conform to the bulge thus not eliminating that problem.

I don't really want to use leveling compound to bring the rest of the floor up to the level of the bulge and the bulge is a bit too big to sand (2 feet wide and it runs all the way down the main hallway).

Does anyone have any recommendations?

Thanks!

Kirk

Kirk:

Simple solution; but it will depend on the thickness of the new subfloor material. When installing the new subfloor "stop" the plywood where the older subfloor begins to rise and fall. Once that's completed fill in the other areas with a patching compound. Would a pic help?

How about this one....ooops, I'll have to work or resizing images:)


http://bal.ifloor.com/files/60/floor%20prep.jpg

Ken,

Thank you very much! This will really help! Should I put anything between the subflooring and the layment to prevent squeaking like, say, a thin plastic or foam layment?

On an almost totally unrelated topic, what do you recommend for measuring the flatness of a floor? A friend of mine used a 12' steel beam that he deemed to be "straight", but I was thinking more along the line of a laser level. Would using a laser level be a problem if the floor was not exactly level? Again, I'm just going for flatness here.

Thanks again for your help!

Kirk

Kirk:

Check this floor prep page I'm working on... It's aimed at gluedown hardwood flooring on concrete but there is a pic that should help you in checking for flatness.

Good Luck

Ken Fisher

www.floridawoodfloors.net/floorprep.htm

Man, you are just captain helpful. This is excellent. I will be working in the basement soon enough, so that web page will become even MORE helpful in a few weeks.

How long can you run the string before you find that the effects of father gravity overcome your ability to pull the string tight? Probably depends on the weight and composition of the string. Is chalk string best for this?

Thanks!

Kirk