We just prepared a Brooklyn brownstone for a green roof installation. It was your typical Brooklyn brownstone: 750 square feet or tar. At least the owners had the foresight to cover the tar with reflective paint.
The roof had 100 years of tar on it. There must have been almost three inches of the stuff:
Our engineer inspected the roof and determined that as long as we took off the tar the roof could hold the green roof. So we cut it into pieces and hauled it off:
Once the tar was off we were down to the original wood planks:
The clients were in a hurry to get the green roof done before they took off for holiday so we worked despite the weather. Once the roof was removed we covered it up really well to protect it from rain:
Unfortunately the rain became Hurricane Bill. And we spent the night catching leaks. (Note to self: learn from this and forever more tie down tarps so they withstand hurricanes).
We then covered the roof with 2 inches of XEPS insulation salvaged from a dumpster and EPDM rubber cover. Don’t believe the hype when the distributors tell you that you need to put nasty toxic glue to hold the stuff down. The green roof will hold it down and if it doesn’t that will be the last thing you’ll worry about because a storm of that force will destroy the neighbourhood.
We measured the EPDM on the street:
And put the EPDM over the insulation:
At this point the roof is ready for a green roof installation!