Install sink drain into cast iron pipe in basement floor?

If you've ever wanted a laundry sink but couldn't come up with a way to drain it, you're not alone. Most older homes have inadequate plumbing, especially when it comes to laundry drains. Often there's only a trapped drain in the basement floor.

And many basements, both old and new, have no below-floor drainage piping at all. These are common problems with no easy solutions. Of course, the best approach is to break open the basement floor and install new drain and vent piping, but this is not always feasible.

Another good alternative, especially when the sewer exits through a basement wall, is to break open a smaller section of flooring and install a below-grade sump pit and pump. Or, you could do what we did, which is install an above-floor sump box and pump, designed especially for laundry sinks. Our home is not that old, but we wanted a laundry sink on a wall opposite the existing plumbing stack.

Bringing new waterlines in overhead was not a problem, but an above-floor drain line was out of the question. An overhead discharge line was our only option. We chose a single-tray, floor-mounted laundry sink for about $60 (Utilatub, model 18F, E.L. Mustee & Sons Inc.

164 St., Cleveland, OH 44142), and an above-floor sump package for about $150. This contained a sump box, 1/3-hp pump and check valve (Simer Sump Co. , 5960 Main St., N.E., Minneapolis, MN 55432).

We fitted the sink with a utility faucet that cost about $40 and we used Type M 1/2 copper tubing and fittings for the supply lines and 1 1/2-in. DWV plastic pipe and fittings for the drain lines. All these parts should be available at well-stocked plumbing supply stores and home centers.

The plumbing hookups for the sink and sump are pretty basic, but keep in mind local plumbing codes. You'll need to vent the sump box and tie the waste line into an existing stack, using a wye fitting. Some codes may allow an automatic vent device, but most will require a dedicated vent that either ties into an existing dry vent or exits the roof independently.