When using puff pastry in the base of a savoury pie, do you need to blind bake it?
A Google search led to Pepperidge Farm's recipe for Chicken Pot Pie. Since they are the big name in the US for puff pastry, I tend to trust them.

They recommend lining the pan with a defrosted, lightly rolled sheet of puff pastry and pricking it with a fork before blind baking covered with aluminum foil for 25 minutes at 400F (~200C). Don't use pie weights, that will interfere with the 'puff'. They don't call for any egg wash or seal, and I can say from experience with the stuff that it isn't necessary.

They fill the baked bottom layer with the chicken filling, add a lattice top of puff pastry, then bake the whole thing (on a sheet pan or cookie sheet) for 45 minutes (or until the filling is bubbly and the lattice top is brown and puffy). 

Be ready to put aluminum foil along the edge if it seems to be getting too brown.