Garage Conversion - connecting to main-house sewer with an ejector pump

Old 04-24-11, 04:01 PM
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Garage Conversion - connecting to main-house sewer with an ejector pump

I'm converting a detached garage into living space. The garage is 30' from the main house. The city requires me to connect the sewer line leaving the garage to the sewer line for the house. The main house has only one bathroom, right above the main 4" cast iron sewer line exiting the house (on the far side of the house, about 50' from the garage).

The main problem is that I don't have a downward slope from the garage to the main house sewer line.

I think that means I need an ejector or macerating pump of some type. I need to understand the best way to do this before I submit for a plumbing/sewer permit. I already have the building permit and have started framing.

The bathroom of this garage conversion will have a toilet, shower, sink and washer/dryer. The kitchen will have a sink and dishwasher.

Can all these six things go into one ejector pump basin? I like Zoeller sump pumps and notice they have some pre-assembled sewage systems that are not too expensive:

Package Systems & Basins | Zoeller Pump Company

My plan is to bury one of these pre-assembled sewer ejector basin and pump systems just outside the garage building and run all six things into it and then exit the ejector pump basin and go through the foundation wall of the house into the basement, across the basement and then connect to the main 4" sewer pipe for the house.

I'd really appreciate any suggestions on things I might run into here and if I'm thinking through this correctly.


Last edited by fromhollywood; 04-24-11 at 05:39 PM.
Old 04-28-11, 07:54 AM
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I certainly wouldn't run the sewer water into the main house. I don't see how that could be legal, not to mention asking for problems. It's supposed to go to the sewer line outside the house, in which case, you maybe able to slope the pipe & eliminate the need for the pump.
Old 04-28-11, 08:14 AM
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To properly size the pump you need to determine what is being pumped and the required solids handling capacity. You must know the voltage, system load (GPM), pipe size, vertical lift, horizontal run, number and type of fittings, and back pressure at the discharge point, if any. Additionally, you must determine whether a single or dual pump operation is desired, how the pump is to be controlled, and if it is an indoor or outdoor

I dont know Hollywood. Your not getting your ducks in a row.

How about installing a small septic? In my area it goes by the amount of bedrooms. 250 gallons per. When all is said and done it may be cheaper then pumps, trench, tie in.

As far as heat and HW for the you weekend getaway this may be what you want. Plus get the 100 gallon propane tank.

This is only a example. You will need to size the BTU accordingly.

PE110-LP - Triangle Tube PE110-LP - 76,000 BTU Output Prestige Excellence Combo Boiler - Space Heating & Domestic Hot Water (Propane Gas)

Now all you need is electric, and cold water trenched. (My moto is K.I.S.S)

Mike NJ

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