Brackets for masonry wall ties are attached to steel-stud backup walls using sheet metal screws. These screws penetrate the building paper when installed. If the building paper is used to keep water from saturating the gypsum sheathing, should these screws be sealed?
Building paper protects the sheathing from water that might bridge the cavity. Screws for tie brackets penetrate this building paper in many locations. Usually, though, such penetrations do not cause a problem. If the cavity is relatively free of mortar droppings, most of the water will run down the back face of the masonry and not the face of the building paper. Mortar droppings often collect on ties and at the base of the wall. If these droppings are small, water reaching them generally runs off one side rather than traveling toward the back face of the wall. It is difficult to seal screw penetrations. To be effective, not only the head of the screw but the area between the bracket and the building paper should be sealed. For most walls, I recommend taking precautions to prevent mortar droppings rather than attempting to seal screw penetrations.