I am about to begin my Sliding Patio Door Replacement, however I have (2) questions:

(1) It is my understanding that you cannot flash directly over the new style Pressure Treated Lumber with Aluminum Flashing, as the HIGH Alkaline content of the new formulation will corrode the aluminum. How do I flash over this new stuff and avoid the corrosion issue?

(2) It was recommended to me to use a Polyurethene Construction Adhesive to seal the new Door Frame. I was told this will hold a seal longer than Silicone Rubber. Is this correct? ... and what type is recommended if correct.

Please advise.

Thank you!