By Chelsea Blakely
We finally got started on the irrigation! I came later in the day on Tuesday, November 13th and got to help Kirk with the irrigation on the left side of the green roof.
Kirk already had the pipe laid out so the next step was fitting them together. If you’ve never done irrigation before, or worked with PVC pipe before, the process is not too complicated.
The irrigation design originally had a single sprinkler head at the center of the modules that would water the area in an even circular area, but this was changed to four sprinkler heads at each of the corners. To accomplish this new design, pipe was laid around the perimeter of the modules and a type of 90° fitting with a third opening on the top was attached at each of the corners. This third opening was for the sprinkler head that will be attached later on.
To attach the pipes we took various pipefittings and couplings* and cut the pipe with special PVC cutters. Pipe primer is then wiped on the outside tip of the pipe about to be attached and wiped on the inside of the fitting that the pipe will go into. After about 20 seconds of drying time for the primer, pipe glue is then applied in the same manner. Immediately after applying the glue, the pipe is then pushed as far as possible into the fitting and held there for about 20 seconds. If the pipe is let go too early, it will slide slightly out of the fitting and increase the chance of leakage. We did this general process for the whole system until the left side of the green roof was completed.
I learned much from this experience. When I heard we were going to set up an irrigation system, I expected a complex system and an equally complex process of building the system. I was pleasantly surprised! It was not such a daunting task at all and I picked up some handy experience along the way!
* A Note on Couplings vs. Fittings: Couplings are a type of fitting that have two openings and run at 180° attaching two pipes into a single line. A fitting is any pipe attachment that has an angle less than 180°, like a 45° or 90°.