There is a lot of confusion about the need for (or lack of need for) property releases to shoot buildings. This likely started when the embodiment of architectural structures became protected by copyright in 1990 with the passage of the Architectural Works Copyright Protection Act. Before then, the drawings were protected by copyright, but not the built structure. Today, that 3-dimensional building is indeed protected by copyright.
And yet, you do not need a release to shoot (and publish) photographs of any building (or parts of a building) visible publicly. Why not? Because the law makes a specific exception for that:
17 USC § 120 . Scope of exclusive rights in architectural works
(a) Pictorial Representations Permitted.—The copyright in an architectural work that has been constructed does not include the right to prevent the making, distributing, or public display of pictures, paintings, photographs, or other pictorial representations of the work, if the building in which the work is embodied is located in or ordinarily visible from a public place.
Now, you can get into trouble for shooting that building, still, if you do not have permission to be wherever you are to make the photograph. For example, if you are set up in Betty’s yard across the street from Bob’s house, shooting Bob’s house, Betty has a claim against you if you didn’t get permission to be there–for trespassing. Bob, on the other hand, can’t complain about you shooting the exterior of his place.
So, as my colleague Carolyn Wright has pointed out before (like here), I can’t find a case where the photographer was successfully sued for not having a property release for a photo of a building’s exterior, even when used in ads, as long as the photo was shot respecting the “publicly visible” rule above.
Of course, it won’t hurt you to get a release signed, but don’t let over-zealous security guards and homeowners bully you out of making your image. Politely explain the law for them (you could even point out the exact provision now, as quoted above) and go about your business.
[One big exception, however, and this has nothing to do with copyright: places relating to national security are a whole other thing. This post isn't going to go into those issues, except to say that in a post 9/11 world, you may have a big fight on your hands if you want to shoot something "sensitive."]