SEATTLE, WASH. — Nothing puts a damper on a hip, urban lifestyle like leaking pipe. So while developers of the trendy new Via6 apartments in downtown Seattle were sure to include tenant pleasing amenities like barn-door-style room dividers and arresting balcony views in the 654-unit complex, they were also considering what piping material would give them the greatest peace of mind for domestic hot and cold water applications.
Poised for LEED Gold certification, Via6 is an eco-friendly, centrally located building consisting of two 24-story towers with a six-story podium in between and three levels of below-grade parking.
The $200 million real estate project, which sits at the corner of Sixth Avenue and Lenora Street in downtown Seattle, began construction in late 2011 and was completed in spring 2013.
Before getting under way, however, the project saw a delay in construction due to the Recession of 2008. Meanwhile, copper prices were extremely volatile. Given the size of the project and its uncertain construction schedule, the owner and contractor decided to look into a variety of piping options.
The design team chose Aquatherm Green Pipe. This polypropylene-random (PP-R) pipe system was chosen because of its hydrophobic nature, which repels water from its surface and keeps the pipe wall from eroding and leaking.
MacDonald Miller Facility Solutions was the mechanical and plumbing installer for the project. The firm had already successfully used Aquatherm Green Pipe on a hospital project and had invested in the tools necessary to complete the job.
Approximately 35,000-ft. of Aquatherm pipe, ranging from ½-in. to 6-in., was installed to provide both hot and cold water distribution for the Via6 apartments. This included all of the domestic water piping from the street mains to the risers and distribution to all the floors. Hot water boilers were installed in the penthouse equipment rooms for each of the two Via6 towers, so supply water piping runs up the length of the building and drops back down to each individual floor.
Aquatherm Green Pipe was used for the 6-in. risers, as well as the 4-in. secondary distribution. The only domestic water piping that isn’t Aquatherm is the piping that serves the end-use fixtures and is imbedded in the concrete structure of the building.
MacDonald Miller was able to fabricate approximately 75% of the piping in its shop, which helped to facilitate the installation. Depending on the size of the pipe, two methods for pipe fusion were used for the prefabrication – butt fusion for anything larger than 4-in. and socket fusion for anything smaller.
The processes went remarkably fast in the controlled environment of the shop, exceeding the contractor’s expectation for assembly time.
“We made spool pieces in the shop according to what was detailed on the plans,” said Randy Borman, piping operations manager for MacDonald Miller. “We then cut them into sections and simply connected them at the jobsite. This really cut down on the field fusion time and helped us avoid a lot of up and down time on ladders.”
Fused for success
Aquatherm, its local manufacturer’s representative, Ridgeline Mechanical Sales, and wholesaler, Harrington Industrial Plastics, provided training to the MacDonald Miller staff on electrofusion, a process that uses special fittings embedded with a heating element to melt and fuse pipe.
To discuss the benefits of prefabrication go to our new Plumbing Talk forum.
This methodology came in handy at the jobsite where occasional space limitations prevented butt welding (also known as butt fusion), which requires larger fusion equipment.
This technique fuses pre-assembled pipes and fittings together using an outer sleeve, which the two pipe ends slide into. An internal stop at the center of the fitting prevents the pipe ends from meeting. Fusion indicators inside the fitting indicate when sufficient melt pressure has been achieved.
“We have become much more efficient in working with Aquatherm pipe, and the learning curve has shortened,” said Mike Kunkel, plumbing superintendent at MacDonald Miller. “We now have about 10 guys trained, so that we can have two to six workers on the jobsite doing installations and two or three fabbing it up in the shop.”
Overall, this streamlined process significantly decreased installation time at Via6.
A solution that holds water
Speed is one thing; reliability is another. That’s where MacDonald Miller really became a believer in Aquatherm technology. When (PP-R) is heated and melted, the pipe and fittings can be permanently joined so the molecules actually bind together, just as they would in an extrusion or molding process.
As a result, the fused material is every bit as strong as the pipe wall, leaving no path for leaks or blowouts. This makes testing much more reliable. Aquatherm pipe cannot be “dry fit” and if it is fused incorrectly, an initial test reveals this fact immediately.
“It’s a solid system,” said Kunkel. “We have made thousands of Aquatherm joints and we have had only a couple of leaks – and those were due to installer error. The guys are used to it now and have accepted it.”
Since Aquatherm pipe can absorb much of the thermal expansion of the water, MacDonald Miller was able to eliminate most of the expansion loops on the Via6 project. And because the heat-fused joints are so reliable, pre-assembled piping sections could be transported to the jobsite without worry that the transport might weaken the connections.