Garage apartment septic hookup options?

[Billboe]

Hello All,

I’m building a detached garage with an overhead apartment this summer and I can see two options for connecting to the existing septic system. I’m in north central Vermont so we do see sub zero temps in the winter. Below is a crude diagram showing the options.

Option 1 - ~90’ straight shot to existing septic tank
+ straight shot
- will pass under a little used but definitely plowed driveway and probably be less than 2’ deep
- there is a ~8' elevation change which may require an elbow or 2 to follow the terrain

Option 2 - ~30’ to tie into existing septic in the basement of the house
+ short run
+ will be able to maintain sufficient depth
- need to penetrate ICF foundation wall
- will need to rearrange some plumbing in the basement (nothing too complicated)
- well comes into the house at that same corner (and water supply from house to garage will be there as well)
- more elbows

What does the collective wisdom think of my options? THANKS for any advice!

Bill

 

[Jeff H Young]

Option 2 sounds easier probebly cheaper less digging cost. Do you know whether the septic system will need upgrades bigger tank?

 

[Sponsor]

 

[Billboe]

thanks jeff! and we designed the septic system for this eventuality, so, all good there.

 

[Jeff H Young]

thanks jeff! and we designed the septic system for this eventuality, so, all good there.

ok well did you decide? site conditions may be a bit differant in real life so that was my opinion based on what I saw you might own a back hoe or something but just seems more economical If cost was no factor Id lien toward the option 1

 

[Billboe]

i do have a backhoe on the back of my kioti tractor but we are getting a dirt guy for the garage excavation so i'd probably just have him do it.

i do like option 1 better as well. however, the thing that bothers me is the fact that it goes under a plowed 10' wide driveway (at ~70' mark) and i'm worried about freezing. i think i can only get about 24" deep (hopefully) but maybe that can be solved with some foam over the pipe when it crosses the driveway. thoughts?

we're in north central vermont and we hit -20 degrees (f) some nights...

 

[Jeff H Young]

I dont work in freezing climate that might be a concideration what does your code allow for minimum buriel on drains I assume its not the same as water pipe which is something like a foot below frost line. Someone very local to you would know building department or contractors but Im war weather guy!