When looking for a minimally invasive method to fix cracked or damaged pipe, in some situations a type of trenchless pipe replacement called pipe relining is the best process. Lining pipe is a way to rehabilitate aging pipe systems without the need for traditional removal and replacement.
Grant Duxbury, Nu Flow America regional manager, explains the process involves remotely cleaning and then lining the existing pipe from a limited number of access points. “The end result is a new pipe within a pipe, extending the life expectancy of an existing system for many years past its original design life,” he says.
Built in 1974, the beachfront Gulfview Club Condominium of Marco Island, Fla., is a 21-story, 265-unit high-rise. Over the years, it sustained the rare toilet sweep issue and an occasional crack showing up on a vertical main, but nothing major. It wasn’t until Hurricane Wilma hit in October 2005 that the swaying of the high-rise put a strain on the bands supporting the verticals and they started snapping.
This put more pressure on the 40-year-old cast iron and cracks started showing up throughout the building. The owners wanted to rehabilitate the corroded and deteriorating lines without causing destruction to the building or inconveniencing the residents.
In spring 2011, Gulfview decided to hire Nu Flow to clean and line one of four kitchen stacks in the building. The cleaning process took four days and the lining was done in two days. Gulfview hired Nu Flow again in the summer of 2011 to clean and line 200 ft. of 6-in. cast-iron domestic water line with an epoxy barrier coating. This ran from the pump room downstairs, 100 ft. underground, to the mechanical rooms located in the center of the Gulfview up to the 10th floor.
Nu Flow then did another project in spring 2012, cleaning and lining the main 4-in. verticals and toilet sweep laterals for four condo stacks (two verticals and two toilets each).
In 2013, the scope of the project included 16 4-in. cast-iron verticals and the respective toilet laterals, as well as a 6-in. vertical laundry drain. To date, 26 4-in. vertical sewer stacks (each 220 ft. long), four vertical kitchen stacks (220 ft. long), one 6-ft. vertical laundry stack (220 ft. long) and 530 toilet sweep laterals were cleaned and lined.
Alan Linardich, community association manager of the Gulfview property, explains there were three deciding factors in its decision to choose Nu Flow, but the biggest factor was the drywall work. The 4-in. verticals were located in mechanical chases with one-hour-rating firewall all around.
“The cost of replacing the firewall and drywall on 21 floors was more than the cost of replacing the pipe itself,” he says. “Nu Flow only needed to open walls every 70 ft. in order to clean and line the pipe. This meant only two hallway openings between the roof and ground floor were needed for the cleanout and the company agreed to cover 50% of the cost of closing up the openings.”
Another factor was the warranty. Although Nu Flow’s normal warranty is 10 years, for this project it agreed to match a competitor’s 25-year warranty. The condos also kept small samples of each liner used to line the verticals (marked with the location the sample was taken from) in case it had any warranty issues to address in the future.
The third deciding factor, Linardich explains, was the crew’s willingness and ability to use the respective drains after 4:30 p.m. each day, so the inconvenience to the residents was minimal.
The tech and the teams
Rehabilitation included inspection with closed-circuit television cameras, the cleaning of each pipe in question and lining of the respective pipe using a stop-and-start method. Hallway walls were opened on the 7th and 14th floors in front of each mechanical chase to provide access to the vertical pipe. Toilets were removed as needed to clean and line the toilet laterals. Overall, around 11,000 ft. of lining was used.
“Gulfview involved two separate technologies,” Duxbury says. “One was a structural lining for its sanitary drains. The other was an epoxy coating to the inside of the pressurized domestic water pipe to end internal corrosion.” The two solutions used were Nu Line, the epoxy barrier coating for the pressurized pipe system rehabilitation, and Nu Drain for the structural lining of the nonpressurized pipe systems.
The drain rehab project was performed over the summers of 2012 and 2013. Up to six technicians worked on the structural drain on and off over the three separate seasons of application.
Four technicians worked during the application of the corrosion barrier to the potable water system. The plumbing portion of the project started in early July 2013 when building occupancy was at about 16%, says Linardich, and it was completed seven days prior to the contracted finish date of Dec. 13, 2013.
Linardich notes the crew worked well together and kept the lines of communication open with his office at all times. “The residents of this high-rise are retired and pretty particular about people working in their condos,” he says. “We had many compliments about the staff and not one single complaint.”
The Nu Flow team, including Duxbury and Account Manager Chris Kruysman, went out of its way to make sure the condo association understood the whole lining process and worked as efficiently as possible in the timeframe, he adds.
Duxbury says the key to success is having a great crew, great products and a customer who understands that although the process is less intrusive than traditional repairs, it still involves a certain amount of resident disruption.
To anyone looking to do a similar project, Linardich suggests: “Go online, do your research and follow up on references. Then educate your residents and keep reminding them that unless you are lining every drain or domestic line in the building, this is not a cure-all.”
To contractors looking to get into this line of work, Duxbury adds: “Embrace new technologies and be poised for growth in the coming times. Pipe relining is a way to ensure a building’s internal infrastructure will last as long as the building itself — without the need for costly and disruptive traditional replacement methods.”