Construction Adhesive

[Halfathumb]

I'll putting down underlayment in a room. How much adhesive per 4 X 8 should I use? Sub floor is in great condition and level

[cndamm]

0 I've always been told to staple the underlayment ever 6".

[Woodenfish]

No adhesive recommended for underlayment. You will thank me later. Install as cndamm suggested would be best.

[mike4244]

I'll putting down underlayment in a room. How much adhesive per 4 X 8 should I use? Sub floor is in great condition and level

Subfloor adhesive is for subfloor sheathing not for underlayment . As posted the underlayment is either nailed down with hand nails made specifically for this or pneumatic staple guns using 1/4" x 1" staples on 6" centers both on seams and the field.
You want to be able to remove old flooring with underlayment in the distant future, hence no adhesive.
mike

[fixtureman]

I use rosin paper or 15 pound felt between the 2 layers helps with squeaking

[Snipe Hunter]

I use ring-shank nails. Lots of them, spaced every 6 to 8 inches. No glue. Never done staples but I know it's an acceptable method.

Just about every component of a home should be installed with the understanding it may eventually need to be removed without too much damage to the home.

[brianwelch]

I use shank nails. Lots of them, spaced every 6 to 8 inches. No glue. Never done staples but I know it's an acceptable method.

Just about every component of a home should be installed with the understanding it may eventually need to be removed without too much damage to the home.

Having taken up a layer of underlayment that I meticulously installed decades ago with ring shanked nails on a 6" grid...I might suggest not using construction adhesive...any more difficult to remove than that might involve incendiary assistance...

[Snipe Hunter]

On the other hand.... what are you installing over the underlayment?

[Halfathumb]

On the other hand.... what are you installing over the underlayment?

Peel & Stick vinyl squares

[Snipe Hunter]

Peel & Stick vinyl squares

Nail it down. Don't forget to use a latex primer on your underlayment. It's cheap and goes on easy and will greatly aid with adhesion.