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Garage Floor Drain

E

Electritek

Registered User
Joined
Dec 9, 2018
Messages
2
Location
Missouri
Needing some info on garage floor drain. Have read codes that garage floor must slope out or to a drain. Have new residential construction with attached garage. The builder installed what he identifies as floor drain. I drained the livewell from my boat in garage floor. Floor is completely flat without any slope to drain or towards door. I swept the water down the floor drain. Two days later garage smelled like rotten fish. I thought P trap was dry so I ran water down drain. Next day whole house smelled like rotten fish. Garage floor drain has a 12" X 12" steel grate. I removed steel grate and looked and there is a shower drain in concrete. After removing the shower drain cover I looked in hole with flashlight. It's not hooked to nothing and merely drains into the gravel below my garage floor slab. Something smells fishy with this drain!! Is this code and EPA compliant.
 
Not into plumbing

But I would say no

How old is the garage??

Is this located in an incoprated city??? Or in the country?


Were there building and plumbing plans??? If so do you have them??
 
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I have encountered but a few residential garage floor drains. They were not connected to the sanitary sewer system and drained to the yard which then drained to the street. The reason for the drain has to do with rain water clinging to a vehicle.

So your garage drains to the gravel under the drain.....well actually your garage does not drain at all. If it were my garage I would permanently plug that hole.

Another reason to not have a garage floor drain connected to the sanitary sewer would be the trap. It would require a primer and that would definitely waste water.

R309.1 Floor surface.
Garage floor surfaces shall be of approved noncombustible material. The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.

714.2 Prohibited Water Discharge.
No rain, surface, or subsurface water shall be connected to or discharged into a drainage system, unless first approved by the Authority Having Jurisdiction.



 
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cda said:
Not into plumbing

But I would say no

How old is the garage??

Is this located in an incoprated city??? Or in the country?


Were there building and plumbing plans??? If so do you have them??
Click to expand...
It's new construction. It's inside city limits and city has adopted all 2012 building/plumbing/elect... codes. I have building plans that show 4 floor drains in my garage. Will have to look and see about plumbing drawings. I spoke with the jackass builder prior to construction and informed him if city would not allow drains to sanitary to run to daylight, grade allows. Can hole in garage floor that drains to nowhere be classified as drain??
 
Will be interesting to see what the plumbing plans look like


Plus wonder what the city saw on inspections

Plus no slope anywhere??

Builder might owe you a garage

I guess the builder called for inspections???
 
Electritek said:
Can hole in garage floor that drains to nowhere be classified as drain??
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Depends, if the gravel you are seeing is part of a dry well system under the garage then it is a drain designed for water run off from your car. It is not a system to dispose of other items into such as oil, gasoline of fish by products.

Dry well
Description
A dry well or drywell is an underground structure that disposes of unwanted water, most commonly surface runoff and stormwater, and in some cases greywater. It is a covered, porous-walled chamber that allows water to slowly soak into the ground, dissipating into the groundwater.
 
The description from the original post sounds like an incorrect drainage system. I seriously doubt it was ever inspected.

Our jurisdiction requires residential 1 or 2 car garage to drain to the exterior, and never directly to the storm drainage system. Residential garage drains are prohibited from connecting to the sewer drainage system in our jurisdiction. If the owner wants to install a trough drain, then it must be plumbed and be pre-treated (ran thru an oil interceptor).
 
All dry wells I have seen are outside the structure.

This could potentially be very dangerous if some gas leaked into the stone below the slab.
 
Paul Sweet said:
All dry wells I have seen are outside the structure.

This could potentially be very dangerous if some gas leaked into the stone below the slab.
Click to expand...

I will second this. Dry wells typically require maintenance. I would hate to see how to maintain one under a slab.
 
If draining below the slab, prepare for cavities to form in the future below the garage floor if not already happening. If it's a ranch house with back-fill and the garage is supported by concrete columns below the garage floor, prepare for additional floor cracking from the column supports when the soil settles.

This doesn't sound good, the water needs to go somewhere, preferably outside.
 
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