Theres no need to model anything else for the buillding, a good displacement, bump and colour map (with possibly a grunge layer in the diffuse channel) should have it lookin pretty good, without the pain of modeling.

Have a google for some brick textures, take them as the basis of the colour map and go from there, a start on the bump/displacement (depending on how you want it to look) would be to simply desaturate the colour map and then go from there.