Hi Folks, thanks for help on this.

I have a 1/4" dehumidifier pump drain line to connect into a 3.5 inch PVC main house residential drain line. Instructions online are 100% clear to absolutely not try anything with a hand drill, so trying to buy a self-piercing taps/saddles but all found online are for thinner gauge pipe or for larger gauge taps. Help??

Here in NC we would have to use a trap and a vent before tying into the 3" pipe. A direct connection such as you are describing would be a code violation.

I agree with the NC plumber.

If you have a pump, check the rated lift / head and distance for the drain line at a rated hose diameter. Find a drain within that distance. Depending on the pump, you may be able to discharge to a first-floor fixture if there is nothing in the basement that is suitable. But remember, the pumps are usually designed for some head pressure, as there would be no need for a pump if gravity alone could be used.

Or, you could discharge through the wall to the lawn, or maybe a sump pit.

I don't know about NY, but under WI code, at normal household pipe sizes, no tapping is permitted regardless of the means, for water or sewer. The only tapping done around here is water & sewer connections under the street.

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Links to the State of Wisconsin Plumbing Code:
[docs.legis.wisconsin.gov]
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I am not a plumber.
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