My installer has connected a sheet of aluminum between the top of a new brick mould window and up about 8 inches to the soffit. The effect is in some homes where they don't put bricks above the upstairs windows they just cap the space he capped the space but he put nothing behind it. He didn't screw the aluminum into anything because it is floating off the wall sheathing by about 2". He used silicon as an adhesive at the Brick mould the side two brick walls as it runs to the soffit and finally at the soffit. When I told him why not build up wood behind it he said he didn't need to and that would weaken the finish. I said the gap behind will cause the metal to travel back and forth like a bellows and the silicone will fail. He said no it will last for a long time. Is he just lying.

I'm trying to seal a rainwater leak. Originating from a space between the top brick molding of a doorway (a sidelight on either side of a centered door) and the brick facade of a cinder block wall. This space between the brick molding and the brick is almost 1" wide. The previous failed attempt to seal this gap consisted of a ton a acrylic latex silicone caulk. As the building does not have gutters, and the 1" gap at the top of the brick molding leads to a larger void between the brick/cinder block wall and the door jam, a significant leak seeps out from under the baseboard onto the interior floor. I have been advised to remove the old caulk in and around were holes are visible and then reinsert an equally significant amount of the same type of caulk. This time without the holes. This has already failed once and will require 10 or so tubes of caulk. Is the best solution to this problem simply to reuse the same materials only with better technique, or is there a better way. thank you for your patience with my conundrum