Rose 1: On the ground floor of the building, there is a caged door that leads to stairs going down. At the bottom of the stairs, turn around and the rose is on some pipes.
Rose 2: In the catwalk near Room 208.
Rose 3: Late in the game, you'll end up In the attic where you are following the blood trail. You see a wooden plank going upstairs. It is in the leftmost birdcage.
Rose 4: In Victor's dream sequence, when you see a Tattoo parlor, hug to the left and continue. Once you see a grave with a rose on it, go up to it and the achievement should unlock.