...also, there's no need to drill directly into the brick. You're not putting a massive load on the wall, and, besides, drilling into brick can be hard work. Drill into the mortar between the bricks. It's quicker, easier, and the fixing will be quite adequate.
Personally I use stainless steel screws for putting anything up outside - don't get the rust stains down the paintwork years later.
A pet hate of mine.