Changes you’ll find in the International Plumbing Code.

With the start of the new year, you have something else to look forward to - new codes. They include the 2012 ICC International Plumbing Code, 2012 ICC International Mechanical Code, 2012 ICC International Fuel Gas Code, 2012 IAPMO Uniform Plumbing Code, and 2012 IAPMO Uniform Mechanical Code.

Before you get too excited, even though the code groups issue 2012 codes, that doesn’t mean the states and local jurisdictions adopt them right away. It can take months or years before the codes are adopted.

However, it is always beneficial for you to have a copy of the latest code. Both ICC and IAPMO offer their codes in printed and electronic formats. You can order the codes on their respective websites: and

They do make it easy to follow the changes in the code. Any section that was modified between the 2009 and 2012 edition has a marking in the margin.

Rather than going back and forth between the codes, let me limit my review of major changes to a single code. The first code I’ll review is the ICC International Plumbing Code. In future columns, I’ll highlight the changes to the other codes.

Graywater systems

Perhaps the biggest change to the International Plumbing Code is the addition of a new Chapter 13. Chapter 13 covers graywater systems. Similar text was previously found in the appendix of the code. By moving the requirements to the body of the code, they make it easier for a contractor to design and install a graywater system.

The primary use identified for graywater is irrigation - in simple terms, watering your lawn. If graywater is not treated, the irrigation must be subsurface. You can only spray graywater if it is properly treated.

Also identified is the use of graywater for flushing water closets and urinals. One of the problems with the new chapter is a requirement to dye graywater if it is used for flushing. This is an archaic concept that was abandoned many years ago. The problem is the dye will stain the floors and walls when the graywater splashes during flushing or an overflow. ICC simply made a mistake by adding a requirement for dying the water. They must have missed the memo.

Venting changes

Certain venting changes will greatly benefit the contractor and help lower the cost of installation. Air-admittance valves are now permitted to vent a chemical or special waste sink. That means you can use AAVs in high school labs and commercial labs. The AAV must be listed for resisting the chemicals that may be discharged down the drain.

Single-stack venting also was added to the code. Most contractors think of this venting method as being applicable only to high-rise buildings. However, it is permitted in any size building. I have used this method of venting for two stories. If you line up the kitchen sink with the laundry tray in the basement, you can install a single 3-in. line to serve as the drain and vent. If you have bathrooms that line up between floors, you can put in a 3-in. stack and connect the fixtures to the stack without additional venting.

The single-stack design requires the contractor to run the stack full size through the roof. And there is a limitation on the distance a fixture can be located away from the stack. For a water closet, the maximum distance to the stack is 4 ft. That distance may be increased to 8 ft. if the connection to the stack is by a sanitary tee. Other fixtures must be located within 12 ft. of the stack. Another thing to keep in mind is the minimum 2-in. branch size.