http://visitmybaltimore.com/video/452/

Let me claim your bonus points : the most publicly accessible location – and perhaps the most significant for the nation – is at Fort McHenry! Go there and see how many you can find.I did.

On the water taxi ride see how many rooftop gardens you can spot - they are green roofs too.

Green roofs also reduce storm water surges - in fact your city requires new developments to deal with storm water surges on site - hence the new Hilton green roof.

A beautiful city, keep up the good work – 200 years of green roofs is hard to beat!

Cheers,
Jol

The owner has to be willing to get involved with maintenance, because green roofs aren’t exactly install and forget. As was pointed out in previous comments above, they are more expensive than most roofs and they usually require special attention to structural support, drainage and access. The key is appropriate design combined with good installation. The designer and the installer have the most influence on a successful green roof, at least to the point wher the owner will have little to no trouble assuming responsibility for it.

They can be attractive, they have readily observable positive effects on the internal and external environments of buildings, and there is just something really cool about having flowers and grass growing on your roof. For companies that have significant infrastructure, the heating and cooling benefits alone can make it worthwhile. As an example, the BP minimarket/gas station at the bend in Key Highway (next to the General Ship Repair Co., across from the Royal Farms outlet) has a green roof. The parent company reportedly has made that a component of their prototype building programs.

I haven’t yet seen the roof on the new Hilton, I’ll have to check that out.

I’ve seen them listed as low as about $9/sq .ft. for 3” of growing media and sedums. More commonly the range is between $14 - $25/sq. ft., (including roofing membranes).

That’s for what is called an “extensive” roof, the cheaper of the two types.

don’t forget that there may be additional costs associated, i.e. additional structure to support the added load of the growth medium. so it’s almost a case-by-case basis for existing buildings.

there are also issues such as life-cycle cost, etc. etc. if you google “green roof square foot cost” there are many resources that quote a wide range of SF costs. but again i believe that this is largely for new construction.