Equally effective will be a self-supporting version of the antenna, although developing a 10' support may be more difficult. It is impossible to analyze in the abstract all of the difficulties that may be faced by individuals trying to get an antenna in place in very restricted spaces. So the best advice is to give your situation careful study, looking for support possibilities in everything you see. For example, if the roof or chimney top is not quite high enough, but a tree in the area is more than tall enough, you can use a sloping rope to connect the two and support the wire antenna. There is no magic about the 10' minimum height selected for this antenna.
Safety is the foremost concern.
The end of the antenna on some bands will carry a very high voltage that can create RF burns if someone touches it while you are transmitting. Although the top height provides good performance, you can lower it if you bend the bottom wire to the side at a safe distance above everyone's head. The change in performance is small enough that it is unlikely to be noticed. The imbalance the occurs from routing the transmission line so that the antenna field couples to it. Let's take up the first two considerations together.