nacarson
08-27-2007, 10:36 PM
Greetings
First of all I wanted to thank everyone for the wonderful advice, material and professional information contained within this forum. Secondly, I apologise for posting and not being a professional, but wanted to tap the advice of some of the gurus here; I hope this causes no offence.
I am installing a sprinkler system at home. Good design (head to head coverage, proper pipe sizes) and good parts (1800 SAMPRS, 3500 rotors, swing joints, commercial timer etc) much thanks to the topics on this forum.
Anyhow I just dug my mainline trench (for carrying about 12gpm w/ static pressure 53PSI). I had planned to install 1.25" Sch 40 PVC which over my length will give minimal pressure loss.
However, I had to go within 1.5ft of an established Ginko tree, and 3ft of a large silver birch (sorry almost typed *****, slip of the finger).
Those trees have root systems that look like Los Angeles freeway intersections: Giant 4+ inch feeder roots criss crossing. I can just about squeeze the Sch 40 in between... But the tree's gonna grow, and a bit of pressure as the roots grow will break the pipe. In some cases the roots are preventing me from getting the trench quite as deep as I should (only 13" or so).
I can't re-route, and I'm not comfortable to cut so many main roots, so was thinking of maybe going Galvanized instead for mainline (Type L copper is 7 bucks/foot or something) which will probably hold out much better.
But I know it corrodes. How long would say some 1.5" galvanized last me for (that way, even if the inside starts corroding, still plenty left before it gets too small)? Heavy clay soil here. Would presumably help avoid the sand backfill (for soil expansion) needed with PVC too.
Would it last a few decades? Any other ideas (I am not comfortable with poly mainline sorry).
Sorry if such basic, simple stuff is too trivial for you pros out there.
Thanks so much
Neil
First of all I wanted to thank everyone for the wonderful advice, material and professional information contained within this forum. Secondly, I apologise for posting and not being a professional, but wanted to tap the advice of some of the gurus here; I hope this causes no offence.
I am installing a sprinkler system at home. Good design (head to head coverage, proper pipe sizes) and good parts (1800 SAMPRS, 3500 rotors, swing joints, commercial timer etc) much thanks to the topics on this forum.
Anyhow I just dug my mainline trench (for carrying about 12gpm w/ static pressure 53PSI). I had planned to install 1.25" Sch 40 PVC which over my length will give minimal pressure loss.
However, I had to go within 1.5ft of an established Ginko tree, and 3ft of a large silver birch (sorry almost typed *****, slip of the finger).
Those trees have root systems that look like Los Angeles freeway intersections: Giant 4+ inch feeder roots criss crossing. I can just about squeeze the Sch 40 in between... But the tree's gonna grow, and a bit of pressure as the roots grow will break the pipe. In some cases the roots are preventing me from getting the trench quite as deep as I should (only 13" or so).
I can't re-route, and I'm not comfortable to cut so many main roots, so was thinking of maybe going Galvanized instead for mainline (Type L copper is 7 bucks/foot or something) which will probably hold out much better.
But I know it corrodes. How long would say some 1.5" galvanized last me for (that way, even if the inside starts corroding, still plenty left before it gets too small)? Heavy clay soil here. Would presumably help avoid the sand backfill (for soil expansion) needed with PVC too.
Would it last a few decades? Any other ideas (I am not comfortable with poly mainline sorry).
Sorry if such basic, simple stuff is too trivial for you pros out there.
Thanks so much
Neil