How do I level OSB

I am installing Dupont Laminate flooring and I have removed my carpet. I know the floor needs to be extremely level, how do I accomplish this?

I guess I don't understand the techniques to determine low and high spots. I tried using a 4foot straight edge but I just can't figure the method to which areas should be sanded and which need leveling cement.

Thanks In advance.

PS. If you can be very descriptive i'd appericate it, I've been laying on the floor trying to figure this out for hours

 

First you need something longer then 4 feet, to do any good. I have a 10 foot aluminum screed(1"x5"x10')

Start in a corner and using a marker pen, map out the low spots, by setting the straight edge in 1 foot increments all over the floor. Then turn 90º and find all the dips and humps in that direction.

Sand the highs, and use layers of roofing felt to fill the lows.

 

Another question:
I need a self leveling compound to go over 3/4 " particle board.
Over that I'll be installing 1/4" Laun plywood, then a solid bamboo which I plan to nail in place.
I'm thinking nothing water based due to sweeling of the particle board?
Brand?
Where to buy?

THANKS in advance!

 

Do you have OSB or particle board?

Particle board is crappy for nailing, it's the saw sawdust and glue that cheap furniture is made of.

 

bigbry, You headed down the road to a big failure!!!!!!


First off, the particle board has to go. All self levelers are water and cement based.

Then you will have introduced a lot of moisture into the subfloor it is going to blow up.

Even over plywood, patching compounds and self levelers add a lot of moisture into the wood subfloor, that takes a lot of time to lower the moisture content of the subfloor.

The ¼" luan, is useless!, unless your just spot shimming directly over plywood(or subfloor grade OSB)

My suggestion is to rip out the particle board, and overlay with 5/8" - 3/4" plywood. Then fasten your Boo to that.

 

Thank You.
I forgot to mention under the 3/4" particle board is 3/4 " plywood.
Using a 2" nail would bring it well into the plywood.
I'll avoid the self levelers as you suggest.
How about this:
Urethane based glue between the 1/4" luan securely fastened with screws again reaching the 3/4" plywood.
Would that form a strong enough foundation for solid bamboo??

 

Uhhh, are you top nailing this floor, or blind nailing this floor, with a flooring nailer???

2" nail at a 45, ain't going to be in the subfloor, especially if the particle board swells and becomes 1½" thick.


I would suggest you rip out the particle board, and overlay with 5/8" - 3/4" plywood. Then fasten your Boo to that.

 

Again thanks.