Sewer Inlet Insulation

[JoeStream]

I'm installing a sewer hookup on my property to be able to use my Airstream as a guest house when we're not on the road. I'm in New England and want to have it available year round, including grey water out.

I intend to use PVC pipe wrapped in heat tape and insulation for the run from the trailer to the inlet. I think this is common practice and I've had success with similar setups in the past.

My question comes with the design of end the sewer line I'm installing to connect to my septic system. Is it enough for the opening to be even with ground level as long as it immediately drops vertically below the frost line, say 3'?

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Or should I have the pipe terminate below ground level in some sort of box which can be insulated?

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[CRH]

Lots of sewer cleanouts have the cap slightly above ground. It doesn't matter as far as winter goes because the water doesn't stand in the pipe.

A good reason to put the cleanout slightly below grade in a concrete, metal or plastic box is so it won't be damaged by lawn equipment or if you drive over it.

[kidjedi]

The box is more initial work, but has multiple advantages: cleaner look above grade (and easier to mow over if it's in the grass), easier to access pvc for repairs, you can store a flexible hook up hose in the box (in the ground), etc.

[JoeStream]

Thanks you both for your advice. So I’m not going to worry about freezing, but I’ll consider a box anyway for the reason you cite. Cheers!

[azflycaster]

If you place the inlet below ground level it is possible for rain water to drain into the pipe. Depending on your location this could be a great amount of water. This could be a very big issue if you are on a septic system.