Hello faithful readers! First I want to start by saying, "Happy Holidays to all!" I’m looking forward to 2016 being a whole lot better than 2015. This year has been very unusual for me personally — a period of change that led to a whole bunch of changes. As tempting as it is to poke fun at personal drama while venting emotions through the catharsis of writing, I suppose I should get down to the business at hand, plumbing business!

It’s funny how after 30 years in this business one can still have questions about something as fundamental as cleanouts. For the first half of my career in New York City, this subject was crystal clear: cleanouts were required at every 90-degree change in direction, period (per the old NYC Code). When I came to California and started designing with the California, UPC-based) Code, suddenly this simple subject became quite complicated.

In the UPC, per section 707, cleanouts are required for every change in direction that exceeds 135 degrees, except for several exceptions. The bottom line is driven by section 707.4(3), “Excepting the building drain and horizontal branches, a cleanout shall not be required on any pipe or piping that is above the floor level of the lowest floor of the building.”

Huh? According to this exception, cleanouts are only required at the basement ceiling and below grade. When first in Cali, I was very confused by this exception, as it basically nullifies the requirement for cleanouts in 90 percent of the building. So, how do you rod out the piping?

As it was explained to me, the vast majority of blockages are cleared through fixture connections, and if that doesn’t work, a no-hub elbow can be accessed as easily as a cleanout, making the cleanouts unnecessary. Makes sense.

What is also funny about this exception is that odd code verbiage of “pipe or piping.” Uh, what’s the difference? Does that line on the drawing represent pipe or piping? But, I digress.

As I spent more time in California, I started noticing cleanouts installed in strange places — like in the vents above urinals in public restrooms. What’s up with that? This provision seems to be associated with section 707.4(1) where cleanouts are permitted to be omitted on a horizontal line less than 5 feet in length, unless such line is serving sinks or urinals.

I have no idea why sinks and urinals are the only two fixtures listed in this exception here, but it explains why there would be a cleanout in the urinal vent for a slab on grade installation. The cleanout won’t fit below the urinal as there is not enough room for the fittings — especially for an ADA urinal. I personally think this exception for urinals should be deleted. It probably dates back to when urinals were frequently used for cigarette butts. The cleanout requirement for kitchen sinks is understandable due to the potential for blockages.

Equally strange is section 707.4 (2) where cleanouts are permitted to be omitted for vertical offsets of 72 degrees or less. Where did the odd number of 72 degrees come from? Well, it turns out there is actually a fitting called a 1/5 bend that is 72 degrees, and it is in the cast iron catalogs, but something tells me you would be hard pressed to actually buy one.

In comparison to the UPC, the IPC is quite basic in its cleanout requirements. Section 708.3 focuses more on building drains and sewers than it does on changes in direction. For changes in direction the rule is that a cleanout is required for a change in direction greater than 45 degrees (such as at a 72 degree, 1/5 bend). Where there are multiple changes in direction, one cleanout can serve 40 feet of pipe.

The IPC doesn’t have the collection of odd exceptions written into the UPC, and it doesn’t differentiate between the building drain and horizontal offset higher up in the building. So, for an IPC job you will have many more cleanouts than a UPC job. It does have a requirement for a cleanout at the base of stack, but I honestly don’t know if that means the cleanout at the vertical to horizontal offset, or above the floor. I’m sure someone who works in an IPC governed jurisdiction will read this and enlighten me, but I believe they mean above the floor. Both codes have a requirement for a cleanout every 100 feet in straight piping.

Although I have not been in touch with the Chicago Code in 15 years, I can only assume that it still has cleanout requirements similar to the old NYC Code, at every 90-degree change in direction. This would only make sense due to their ongoing use of lead and oakum joints — a practice as old as the city itself. Yesterday, I learned that not only does Chicago still require lead and oakum hub and spigot joints, but apparently they only allow five foot lengths of pipe rather than 10 foot, doubling the number of lead and oakum joints. That’s crazy!

Anyway, once again, have very happy holidays! Don’t overload your sink with festive scraps, lest you need to resort to hunting for the nearest cleanout! 

Timothy Allinson is vice president of Engineering at Murray Co., Mechanical Contractors, in Long Beach, Calif. He holds a BSME from Tufts University and an MBA from New York University. He is a professional engineer licensed in both mechanical and fire protection engineering in various states and is a LEED accredited professional. Allinson is a past-president of ASPE, both the New York and Orange County chapters. He can be reached at [email protected].