Habitat has done at least two article about this. I found them by typing "noise law" in the Search box on the front page.

The first one explains "Local Law 113 of 2005," which went into effect last year. That should provide you with the ammunition you need. It's at http://www.habitatmag.com/publication_content/2007_october/web_exclusive_adaptations/noise_complaints_and_the_new_2007_law

There's also a newer article at
http://www.habitatmag.com/publication_content/habitat_s_purchasing_primer_news_for_new_buyers/noise_complaints_when_is_loud_allowed

Since terraces and patios are part of the structure and property of the co-op and residents are only given the right to occupy them privately, I would say that the co-op would be able to provide guidance on their use and maintenance. (Don't co-ops restrict decorations, planters, floor covers, etc. on terraces and patios?) Consequently, regulating human activity in these areas, knowing that such structures and patios may be adjacent to the windows of other apartments, can be subjected to house rules. Some may argue that noise coming from the street, i.e., sirens from ambulances, fire trucks or noise from pedestrians cannot be regulated. This activity is somehow regulated by laws and ordinances to make the life of city dwellers a better place to live.

In cases where there is no prescribed house rules prescribing the reduction of noise after a certain time of the night, boards can always appeal for consideration to neighbor. Finally, as neighbors, we may speak with the offending neighbor by being tactful. For example, my neighbor would go to the terrace to speak on the cell phone at 11:00 pm and the voice carried over my bedroom. The neighbor's terrace is just adjacent to the bedroom. When I saw the neighbor a day or so later in the hall, I only commected to the person that I was also part of the conversation and the confidences the previous night night. I reminded the person that I was resting in my bedroom and the conversation was totally audible. I reminded the person that for total privacy, the apartment should be used. The person laughed and never used the cell on the terrace.

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