One Well Servicing House and Outbuilding (New Const)

[D C]

I'm planning a new construction project and want to educate myself on how things should be done.

I'll have a house and an outbuilding garage, both new and a new well, and would like to have both served by the same well. What is the proper way to approach this?
Multiple pressure tanks?
Single/multiple switches?
Garage feeding off house tank (even though it's 100' away)?


On the other end, literally, I suspect 2 main lines into a wye upstream of a single septic tank is the way to go. The only practical issue is that the septic field will be on the far side of the garage from the house, so the garage drain will have to run back towards the house to connect upstream of the tank.


Thanks!
Dave

 

[Valveman]

You only need one pressure tank and one pressure switch. The tank and switch must stay together. They could be at the well, at the house, or at the garage. The only check valve you need is the one on the pump, so water will go back towards the well if needed.

Now your other options are to use a large pressure tank and let the pump cycle on/off while using water, or to use a CSV and a small pressure tank so the pump will just stay running as long as you are using water. Pumps love to run, but won't last as long if they continually cycle on and off.
See this.

 

[Sponsor]

 

[Reach4]

If your outbuilding is not heated throughout the winter, you will need to take that into account... along the lines of a frost-free hydrant, the system should be able to drain the water out. PEX is said to usually be able to survive being frozen although it is not guaranteed for that. Copper or CPVC will burst.

On the other end, literally, I suspect 2 main lines into a wye upstream of a single septic tank is the way to go. The only practical issue is that the septic field will be on the far side of the garage from the house, so the garage drain will have to run back towards the house to connect upstream of the tank.

I would consider a second entrance port on the septic tank, if your septic guy says that is practical.

 

[Smooky]

You might need a pump for the waste water if you can not get 1/4 inch per foot fall on the drain pipe. Are there restrictions on the septic system depth? Maybe you can get gravity if the site is sloped or if you shape it up just right.

 

[D C]

If your outbuilding is not heated throughout the winter, you will need to take that into account... along the lines of a frost-free hydrant, the system should be able to drain the water out. PEX is said to usually be able to survive being frozen although it is not guaranteed for that. Copper or CPVC will burst.


I would consider a second entrance port on the septic tank, if your septic guy says that is practical.

Thanks guys.
My plan is for the outbuilding to be heated through the winter, though I suppose it would be a good idea to plan for the event when that's not the case.

It sounds like the reasonable option would be to put the pressure tank in the house (closer to the well) and run a sub-grade PVC conduit, maybe 2-3" dia, over to the outbuilding. Then I can run a length of PEX or whatever else through that conduit to the outbuilding.


On the drain side, I do have plenty of slope, and so hope to avoid a lift pump. The septic field is going on a low spot relative to the house and outbuilding, so I think I can gravity-slope everything ok.

Hadn't considered a dual-inlet septic tank. That might be best, depending on how far away from the house I can put the tank. Does that even matter?

Dave

 

[Smooky]

Most septic tanks have three inlets. The reason is so you can turn the tank what ever way you need too and still have a straight path to the tank. In most cases, it is cheaper to go to the closes drain and connect them together rather than to run two lines going to the same place. How you run the drains would depend on you garage location in relation to the septic tank and the house.

NY Tank manufacturer showing 3 inlets:
http://www.grimmbldg.com/septic_tanks.php#3

 

[Reach4]

Hadn't considered a dual-inlet septic tank. That might be best, depending on how far away from the house I can put the tank. Does that even matter?

I was thinking I had two separate inputs, but I guess I am not sure. Next time I get the tank pumped, I will try to find out. I don't find much on adding a second input to an existing tank. http://www.kistner.com/Tools/Portfolio/Upload/Project596/Docs/PG 08 2014.pdf offers a tank with 3 inlets.

I would think that a separate inlet would make clogging less likely rather than doing a 180 degree long sweep.

 

[D C]

I suppose the one catch in the plan is that I want to build the outbuilding first, and have it up and running before the house is complete. I suppose that just means re-routing the supply line when the house is complete.

 

[Boycedrilling]

If it was me, I would put a bathroom in the outbuilding. Insulate the bathrooms walls, install a wall heater for winter and put the tank, pressure switch and control box there.

Just put a tee in the underground water line to run to the future house.

 

[D C]

If it was me, I would put a bathroom in the outbuilding. Insulate the bathrooms walls, install a wall heater for winter and put the tank, pressure switch and control box there.

Just put a tee in the underground water line to run to the future house.

Not a bad idea at all. The outbuilding will have a full bathroom (thus the reason for water out there). Could work in a closet under the stairs for the tank/switch. The building will be insulated to above-code for a dwelling, and heated, so I don't expect it to freeze, but localized wall heat is good insurance.

The tee would be located after the tank in your proposal, correct? Results in a little back-tracking to get back to the house, but if I run 1" PEX to the house from the outbuilding, I don't see it being an issue. Heck, I could do the sprinkler control and back-flow preventer from the outbuilding, too.

Good things to think about. Thanks.

 

[Reach4]

Maybe 1-1/4 poly (cheaper than PEX) teed at the well. The bigger pipe will minimize pressure drops. For a given nominal size, HDPE (polyethylene) is normally bigger than PEX.

You will want info on how to pass the pipe through your foundation. It may be subject to local requirements.

 

[Valveman]

OK if you are running sprinklers, especially through 1" pex, a CSV would be beneficial. Depending on the size of the pump, you may not even be able to flow enough through 1" and a backflow preventer to keep the pump from cycling. You can set up your sprinkler zones to have only one sprinkler, three sprinklers, or as many as the line, pump, or well will allow and the CSV will keep the pump from cycling. The CSV will also allow you to use a tank as small as 4.5 gallon in size, which will easily fit under the stairs or above a water heater.

However, the CSV needs to be installed before the pressure tank and before any water lines tee off. So you can use one of the Pside-Kick kits if you tee off to the sprinklers and other buildings after the pressure tank in the outbuilding. Or if you want to tee to the irrigation and other building from underground, before the line comes into the outbuilding, then the CSV12550-1 can be installed in the well. The little pressure tank and pressure switch can still be installed in the outbuilding or any other building as long as there is no check valve keeping the tank from emptying backwards to the other lines when needed.

 

[Smooky]

You could build a well house and put everything in there. Insulate it well and a small heat source should keep it warm enough. Most folks around here use an incandescent light bulb as a heat source

 

[Boycedrilling]

PEX is copper tube size. Poly pipe can be either copper tube size (cts) or iron pipe size (IPS). 1" cts is about the same ID as 3/4" IPS pipe. By the way pvc pipe is IPS and cove is cts.

Pex is also substantially more expensive than pvc or poly. For 1 1/4", PVC is the least expensive. Poly is 2-3 times as expensive as such 40 pvc. Pex is over 2 times the price of poly. That being said, depending upon the application, I do use all three of these materials, for either interior plumbing or underground.