[Tidybuoy]

My summer project is to re-locate my split system A/C & Furnace to the attic as well as install a tankless water heater in the attic. I got a couple of estimates and the cost was shocking and I will have to do some of the work myself, in advance of the actual A/C install. Fortunately, one A/C company gave me a detailed estimate and also told me the code requirements.

Code requires separate, dedicated gas 1" lines to each device and must be "T'd" at the meter. This is something I think I can handle but when I was looking at gas pipes at Home Depot, there are black pipes and also Green coated pipes. I'm wondering what's the difference between these two types of pipe. I hesitate to ask the min-wage employee at Home Depot.

Thanks for any advice