Here is a great picture of a green roof installation for a Brooklyn brownstone.
I like it because it is simple. There are a lot of ways to install a green roof on a Brownstone. They simply have to meet the low weight requirements but apart from that you can do it many ways.
This is one of the best ways I have seen because of its simplicity, which translates into lower costs and less things to screw up over time.
Eco Brooklyn has installed this specific water retention and root stabilizer and we like it a lot. We’ve actually done a green roof installation on a normal slant Park Slope brownstone without the water reservoir using this water retention and root stabilizer mat.
Brooklyn gets an average of four inches of rain per month year round. Check out this graph:
Brooklyn gets a nice amount of rain, not too much and not too little. Just enough to keep plants green without going Seattle on us (aka piss ass rain all the time).
This means that a Brooklyn green roof installation doesn’t need much water storage in terms of water retention mats and reservoirs.
As Brooklyn green roof installers we need to cover ourselves professionally and thus need to build for that 100 year drought. So we make sure our green roof installations have plenty of water retention. This avoids call backs from unhappy customers and green roofs gone brown.
But we balance that with a healthy disdain for putting more products on the roof than we have to, since that drives up consumption as well as the price of the roof. High on our list is to minimize product manufacturing since the Western world consumes too much. We also want green roofs to be affordable to middle class homes, so only the essentials are included in the green roof material list.
The happy balance we have found is very similar to the green roof image above, often without the water reservoir. Below those layers we would add lots of insulation and an EPDM rubber waterproof layer. We’re even increasingly forgoing the roof barrier because studies are showing the the EPDM works just fine at keeping the roots out of the house water seal.