Rough In for lawn irrigation system?

[starquestMM]

First post, but I've been lurking here for while for useful ideas.

I'm working towards finishing my existing garage's interior and would like to leave a rough in for a future lawn irrigation system. What do they require? I've searched the web and came up blanks.

The water meter is in the middle of the front yard and then the service line (3/4" copper) runs directly into the garage from there. Once inside the garage, the first thing is a tee that feeds and exterior spigot (1/2" copper). After the tee, the supply line goes to a pressure regulator.

My service water pressure is really high. IIRC it was 110psi last time they checked it. Is that too much for an irrigation system inlet?

It would be possible to tie into the service line outside the house, is that a better idea?


For power, there is a dedicated circuit for the garage/shop outlets with an outlet box pretty close to the spigot. From there?

Thanks, Mike

 

[buzz4041]

My system only requires the wiring for the solenoids to come into the garage control box. No need for any piping. Also the electrical supply demand is very small and can be plugged into any standard 110 outlet. What kind of system are you planning on ?

 

[starquestMM]

What kind of system are you planning on ?

Good question, I don't know. I was going to let a pro figure that part out.

Basically just the front yard to start, which is small at ~2500sq but does have about 10' of elevation change.

 

[Ulrick]

Check out there website, might give you some ideas.

http://www.rainbird.com/homeowner/education/index.htm

My system has a 3/4 Waterline to the valves and the timer is a standard 110 plug in.

 

[starquestMM]

That does help. That first video had the irrigation being fed from the supply line before it entered the house. That takes care of the plumbing part of it.

If I won't need a pump, it doesn't look like I'd need power either. I was making a mountain out of a mole hill

 

[CNGsaves]

First question is whether water comes from Seperate Well for sprinkler system? Or are you going to use city water?

For city water, I'm sure your code will require a Back-Flow device as they don't want any possibility for "contaminated water" to get back into city water supply. These can be bought cheap at Lowes or HD and install yourself saving bunch of money vs sprinkler company . . . . and also may prevent "Annual Fee" monitoring that your city may try to impose.

At my prior house I had 6 zone Rainbird system installed where they pulled in the underground plastic pipe using vibratory plow. Me and surrounding 2 neighbors all bought systems at same time to get better pricing and company did all 3 houses in couple days!!

Only thing that went into garage was low voltage wiring for the timer hung on wall that required 120 volt plug-in (ie in convenient place next to door that went into house). This was from underground then through plastic conduit and LB where it entered the garage (ie 90 degree turn with the removal plate). Plastic conduit continued from outside entrance through LB and over to the timer panel.

If I were to do it over, I'd save bunch of money and have them layout design and pull the pipe leaving stubs out of ground for me to finish. Also, I would get more zones so a separate zone(s) could be setup for drip irrigation where I might need it (ie houseplants on porch / garden / etc).

Also, make sure you include a blow-out port in the PVC pipe (ie a female 1/2" NPT thread that is below the back-flow valve) where you can screw in an adapter for air compressor blow-out to winterize. Of course will need appropriate shutoff valves so that air during blow-out can only go out through the zones. Blow-out port is just plugged during normal operation of sprinkler system in spring to fall.

IF on city water and water source is in house basement (likely 3/4" or 1" copper), make sure you have shutoff valve to isolate the sprinkler system from rest of house water so that water pressure can be back drained into your sump pump from copper lines within the basement. T off the main copper line run to outside with a downward drop to install normal water spigot and hose so that water can go right into sump pump when you are doing the winterize step.

If your local sprinkler install company offers a free class for "Do It Yourselfers" then I'd attend that before deciding what to do. Good luck!

EDIT: Reason for asking whether city water or your own well, is that city water cost to keep that yard green might be shocking!! With my 6 zone system on 1/4 acre lot, water bill climbed to nearly $200/mth!! Payback on putting in own well may be less than 5 or 6 yrs if your water rates are real high.

 

[4EyedTurd]

Check out www.sprinklerwarehouse.com I started researching this for the house and there is a lot of info there. I believe it's rainbird that has a form you can fill out and they design the system with the right heads and sections.

 

[yardpro]

i am in the irrigation business.

pressure above 50 psi is really not good on an irrigation system. It causes misting, etc.

Flow rate is MUCH more improtant as it determines how many heads you can run per zone.


We normally tap in directly at the meter as we have more volume available there. Most residential supply lines are 3/4 which is not good for irrigation. with 3/4 you can only get about 6 gpm before passing the 5ft/second velocity mark.

You want to stay under 5fps.

remember that the more volume the better. We use nothing smaller than 1" pipe. no stepping down pipes, etc..


As for you garage you will need a spot to mount your controller. It will need power. You can install it near an outlet and simply plug it in.

you will only need one small conduit going outside for the control wires for the valves.

I would not install any of the plumbing inside the garage. locate in a below ground box outside.

any questions email me.

 

[SD_R/T]

pressure above 50 psi is really not good on an irrigation system. It causes misting, etc.

This is true, to a point. Might require some clarification for the OP.

50psi at the sprinkler is generally not good (unless you have a large rotor head which are designed to work better at higher pressures). But 50psi at the start of the system could be problematic depending on how far the irrigated area is from the start of the system, especially since most typical sprays are designed to operate around 30psi. And 2500 SF is nothing to sneeze at, either. Lots of psi can be lost between the start of the system and the time it reaches the sprinkler head (through pipes, backflow, valves, etc).

But as you mentioned: special care about pipe sizing and layout are important to get things working properly. The 5fps is indeed key. Some of the links provided are good ones.

In short, having 110psi at the start of the system is good as it's always better to have too much pressure at the start of the system than too little. You can always install pressure-reducing valves to dial things in at the sprinkler heads. Creating more pressure (adding a pump, electrical, etc) is 'generally' more of a hassle and costly than reducing pressure.

Good luck OP! Use the links for sure.

 

[starquestMM]

Thanks, I saw a pressure reducing valve setup in some of the links provided. Its good to know that is standard practice as I'm sure it will need one.

 

[pinebarkauto]

You may want to consider a separate meter for your irrigation system if your town allows you to not pay sewage charge on irrigation use. If allowed, I would put a spigot on that meter for car washing, pressure washing, etc..

 

[lateracer]

I would get more zones so a separate zone(s) could be setup for drip irrigation where I might need it (ie houseplants on porch / garden / etc).

^^^This.

I wound up adding in an additional zone for drip irrigation after my system was all routed, wired, buried, etc. It worked, but it looked like an after thought. 1 additional zone can run a large drip system and can have inline manual valves that let you create little mini-zones.

 

[4EyedTurd]

Where is your control box mounted? Outside or inside? I'm trying to decide if I should run the wire to the valve bank out thru the soffit area and down the brick or down in the wall and out. All the while trying to keep it as close to invisible as possible.