To answer this question lets evaluate if there was no art in architecture. What would happen if “form did follow function” and a house was a “machine for living”? Interestingly rationalists would really enjoy this architecture as would a number of architects. It could be argued that the lack of art is a purposeful artistic process?
I do not mean to make your head hurt, but my point is one cannot avoid art in architecture no matter how hard you try. What we can avoid are buildings that are mundane, tired and copy other mundane architecture. The art in the buildings below is there but it is weak and unemotional. How many times, in how many locations have you seen this shopping center?
Photo Courtesy: http://bizmology.hoovers.com/
The architecture in this shopping center is like a cheap poster. It evokes no emotion for most people and negative emotion for some. Because you have seen it in so many locations, it creates no sense of place. It could be anywhere.
I believe that for a building to be “good art” it either has to be very original and well designed mastering, form, space, balance, proportion, rhythm, scale, light, contrast, color and many other factors. The building needs to be site specific and reflect the program in form and spirit. This is what makes a good architect an artist.
Below is a photograph of LeCorbusier’s Chapel of Notre Dame du Haut. For me this is architecture at it’s highest level. Every shape, overhang, and puncture has a functional and spiritual purpose. In the hands of a master, architecture can be elevated from the mundane to high art.