Installing multiple floor types

[mur]

I'm sure this has been cover before, couldn't find it.

I'm going to be installing Bamboo flooring in my living room and Kitchen.
my living room is 3/4 lower than the kitchen. Right now it is half plywood(3/4)
and half hardwood.
Can I lay the bamboo over the exsisting hardwood floor (Perpendicular)
It seems pretty level, wasn't sure if it's better to lay ply instead and keep things consistant.
If I do lay other the exsisting Hardwood, is there a can for squeeking?

Also since my living room is 3/4 lower than the kitchen, I can not place plywood in kitchen and have both surfaces the same level. Can I place the Bamboo directly on the Subfloor?

Another question if I may
Is the Quiet Walk Underlayment (including Vapor) any good, Is there a better one?

Thank you

[pushkins]

The best option would be to try to keep all the floors the same level, ply wood sized appropriately would do the job if that's what you choose to do.

As long as the floor being nailed to is sound then there is no problem attaching new bamboo flooring to the existing flooring material, your best option is to lay the new floor in the opposite direction to any existing flooring material.
The best solution for squeaking floors is to make sure the sub floor or existing floor is soundly nailed down to start with. Make sure you nail the new floor correctly, nailing every 6" if needed.

If it were me I'd build up the living room floor to make it all the same level as the kitchen. (make sure any doors etc... can accommodate this) Then I'd lay my new floor across the entire area to make it all look as one.

A good underlay should always be a vapor barrier. Quiet walk is not one I am familiar with.

[mur]

The best option would be to try to keep all the floors the same level, ply wood sized appropriately would do the job if that's what you choose to do.

As long as the floor being nailed to is sound then there is no problem attaching new bamboo flooring to the existing flooring material, your best option is to lay the new floor in the opposite direction to any existing flooring material.
The best solution for squeaking floors is to make sure the sub floor or existing floor is soundly nailed down to start with. Make sure you nail the new floor correctly, nailing every 6" if needed.

If it were me I'd build up the living room floor to make it all the same level as the kitchen. (make sure any doors etc... can accommodate this) Then I'd lay my new floor across the entire area to make it all look as one.

A good underlay should always be a vapor barrier. Quiet walk is not one I am familiar with.

Thanks for the input,

In order make everything level I'd have to put 3/4 ply in living room.
So I would basically be placing bamboo on 3/4ply for living room and Bamboo directly on Subfloor in Kitchen. I wasn't sure if this was ok or not.