Sewer Pipe Solutions

[bruce1234]

Just learned from home contractor that when he set the new house foundation they set it too low for the home sewer line to be the required 36″ below grade. He suggest that the only available option is to install a pump that would feed the home sewer line to the public sewer. I don’t feel this is a sound solution when you factor the yearly operating cost of the system and the assosiated proble caused by a power outage and pump replacement and repair.

My question is this, is it possible to install heating cable or other similar product to the sewer line to allow it to remain the current 18″ below grade and insure that the sewer line would not freeze? Does such a product exist and what is the associated cost? Thanks

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[Retired plbg1Participant]

What does your code say for depth of sewer. The UPC calls for pipe to be no less then 12″ it depends on how cold it gets where you live. You could use heat cable , can you have dirt hauled in to raise el. of ground.

[John Aldrich1Participant]

Plummingathome, as I interpret your inquiry, it sounds like the elevation of the sewerage outlet pipe is too low to allow the sewage to flow by gravity to the public sewer main. If this is the case, then the appropriate solution to the problem is to install a sewage ejector pump, and lift all of the sewage generated in the house to the required elevation to allow for gravity flow of the sewage to the sewer main. If the sewage ejector pump and pumping pit is located in the basement, or crawl space then there is no need to protect the pressurized portion of the sewerage pipe from freezing. However, if the pumping facility is to be located outside of the house, then that portion of the sewerage pipe that is full of water at all times, and is above the maximum estimated frost depth, must be protected from freezing with insulation and an electric heat tape.

An alternative to the use of the electric heat tape is to install a vacuum breaker valve at the apogee of the pressurized portion of the sewer pipe, and use a pump that allows the sewage to flow back into the sewage pit when the pump turns off thereby draining the pressure sewer pipe. Be advised that the vacuum breaker valve will require frequent maintenance so that it does not become clogged with sewage. If the vacuum breaker valve becomes clogged and does not allow air into the pressure sewer pipe, and it is below freezing, the sewage will not drain back into the pumping pit, and it will then freeze solid and potentially causing the pipe to burst.

[robertgfParticipant]

the reason the sewer has to be below the frost line is so the ground does’nt heave and push the sewer up and out of fall

[Robert Stephen MortonParticipant]

plumbingathome. The reason licensed contractors are employed is because they have responsibility for their actions.
Scenario- If your builder built the foundations on the wrong block, who would be responsible?
your builder seems to have stuffed up or was he working under your instructions for the foundation height?
Bob

[plummingathomeParticipant]

Thanks for all the replies and information.

[nicktheplumberParticipant]

plumgingathome,

I’m unclear about one thing, but it is an important thing in your story. Unless you have any fixtures in your basement that must drain UP to a sewer line at 18″ below grade, there is no reason that all of your other (i.e. 1st storey) fixtures can’t drain into a deeper sewer line below your local frost level).

If you do have some basement fixtures that are situated on a basement floor above frost level, I don’t see why you can’t still lay the building and outside sewer drain at a lower level (it may require some outside trenching and inside slab demolition) unless the municipal sewer tie-in is also “too high” and doesn’t allow enough elevation in the drain layout. If that’s the case, you have a legitimate beef with your municipal sewer agency…

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