New Engineered Hardwood Flooring over Existing Vinyl Tile

Hello and thanks for reading.
I am trying to lay hardwood flooring over existing vinyl tile using a floating type installation.
The vinyl tile can not be disturbed as it has a high probability of having asbestos.
There are some slight bumps around the room which would not meet the requirement of having the room level to 3/16" per 8ft. The space is about 1/4" which leads me to my first question. How would I solve that problem? I dont think I can use plywood because I cant nail into the vinyl tiles. Any suggestions?
I've been looking everywhere and asking the homedepot people but they have no idea.

For the layout, here is a description of the floor looking from above.

Here is a link to the floor plan.
http://img221.imageshack.us/my.php?image=secondfloor0002bx1.jpg
How should I proceed with the layout?
Should I start from the hallway and proceed to the right?
Or should I start from room on the right?

Thank you for your time.

 

I would say start with your longest wall and square your room up so you do not have slanted cut on one wall.
Run a string line and get a $15 laser to check your wall squareness.

We are to assume the substrate is concrete due to the humps under the vinyl,correct?

If it is wood or concrete find out what those humps are before you start.
You may want to think of leveling. Your string line will tell you how bad it really is.

To use a string line:
Find a good center point, run your line out from it at the floor level as another person is moving the line in a circular motion mark the low or high spots with a pencil or marker.

 

This installation will take place on the second floor. I believe it is wood under the vinyl and not concrete.
Please take a look at the floor plan. Its a lot better than the symbol drawing I had earlier.
Also, should I use T-moldings at the doors? or can i just go straight across and into both rooms?

http://img221.imageshack.us/my.php?image=secondfloor0002bx1.jpg

Click on the picture to make it bigger.

 

Find out what the bumps are.
Let me know.
I will be here.

 

The bumps are just parts of the vinyl tile that has been roughed up from wear. I have no idea what is under it and I cant check because the tile might be asbestos. It is 9x9in and the tiles are very old.

The slight depression is in the middle of the room on the right. Its about 1/4" unlevel when checked with a straightedge placed diagonally facing the door. When checking the floor going parallel it doesnt seem to be that unlevel maybe 1mm.

Also, should I lay out the flooring starting from the hallway or from the room? And should I use a t-molding to separate the rooms and the hallway or should/can I just lay the floor without any interruption?
Thank you for your time and your help.

 

Ok so today I used a string to check where the dips and bumps are. Seems that its slightly higher in the corner farthest from the door in the room on the right. Then it dips 1/4" for about 2 feet then it returns to the same height.
In the middle of the room there is the same thing, a higher bump and then around it are dips of 3/16".
What should I use to level out the areas that dip?

 

Look at the sticky post above that is titled "concrete floor prep"

Paste the picture links into your browsers address window and hit enter.

 

Perry has some excellent pictures of properly done floor prep.
It is a little more than work than it appears.

But if your are willing we/he can walk you through this,and save you about 3-$500 or more.

 

Hey
so yesterday I tried to level the floor using LevelPro 555 from HENRY. It leveled about 1/8" but there is still about 1/4" left. Should I level it some more?
Also, will there be a problem with weight if I use the floor leveler on the second floor? I'm afraid it will be too heavy.
Any suggestions on brand of mud to use? The bag that I got from HD was 37 dollars for 40lbs and it covered about 40 sq ft.

 

I am about to do something similar but I pulled up the tile.

How did the Levelpro work. I just bought a bad to help with some low spots.