For house-hunters in New York, outdoor space has always been a key amenity. While terraces, balconies and private gardens also top the list, larger outdoor spaces like roof decks and community gardens are perennially popular with both current and prospective residents -- and even more so lately, as the COVID-19 pandemic has made fully public spaces unappealing to many.
If you’re not among those lucky enough to already have a roof deck on their building, it might be worth considering installing one - depending on your structure, budget, and the value-add such an undertaking would represent. We spoke with a practicing architect to find out how feasible it is to add a roof deck to an existing condo or co-op building, as well as the administrative and safety concerns that go along with it.
What’s Necessary to Convert Your Roof?
Giulia Alimonti is an architect with DeSimone Consulting Engineers, a full-service national engineering firm headquartered in New York City with offices around the United States (www.de-simone.com). She is also a member of National Women in Roofing (NWiR) and Chair of that organization’s NYC Council. According to her, the basic requirements set by New York City to determine if your roof is suitable for a roof deck include the following: “First, there are structural requirements,” she says, “Because of the variety of roofs and structural decks supporting them, I recommend starting by evaluating and reviewing your roof’s structural composition; whether it is a concrete, metal, or wood deck, and its capacity to safely support both ‘live’ loads - such as human occupants - and ‘dead’ loads - such as the roof structure itself.”
Alimonti adds that retaining a qualified structural engineer as part of the design team as early as possible in the process will inform a lot of the decisions to be made down the road. For example, the structure of the roof deck will inform how many people will be allowed on the roof at any given time. Depending on the occupancy limit, the deck may qualify as a ‘place of assembly,’ and therefore may have to operate under the more stringent building code requirements that govern such spaces. This may include length of egress, stair widths, and bathroom facilities.
“It is important that all future occupants are able to safely access and exit the roof deck areas in normal times and during an emergency.” says Alimonti. “The occupants - residents of the building and their guests, maintenance staff and firefighters - will have to use the stairs. Building code requires two stairs to the roof, and the width of the stairs will also inform the number of occupants.”