GUEST COLUMN: Repiping or Lining: Strategies to Keep Multifamily Plumbing Systems Running Smoothly

Given the sheer number of structural, mechanical and electrical components within a typical multi-family structure, it’s easy to overlook a building’s plumbing system when major problems aren’t evident. Yet low water pressure, leaky pipes and stained, discolored water are all signposts to larger issues – potentially even system-wide failure. The longer these linger, the worse they can get.

Given the sheer number of structural, mechanical and electrical components within a typical multi-family structure, it’s easy to overlook a building’s plumbing system when major problems aren’t evident. Yet low water pressure, leaky pipes and stained, discolored water are all signposts to larger issues – potentially even system-wide failure. The longer these linger, the worse they can get.

Each plumbing system in a home or multi-family building was uniquely installed, and has its own distinct characteristics. Accordingly, plumbing systems in some buildings perform well for years, while others fail well before their design lifetime. Why this disparity? Largely, the success or failure of a plumbing system is dependent on three basic variables:

Material type and quality: Plumbing pipes in older multifamily structures are likely made of lead, galvanized steel or copper. In 1986, Congress banned the use of lead solder containing greater than 0.2 percent lead, and restricted the lead content of faucets, pipes and other plumbing materials to 8 percent. Yet this so-called “lead-free” brass can still legally contain up to 8 percent lead, and plumbing systems installed prior to 1986 can contain high levels of lead from both plumbing components and lead solder.

Likewise, galvanized pipes will corrode over time due to high levels of iron or zinc in common tap water. These pipes will discolor water, impart a “metallic” water taste, and over time, develop poor flow from mineral buildup blockage. Despite its longtime acceptance among plumbing professionals, copper piping is also subject to failure from pinhole leaks.

Design and installation: The World Health Organization states that a plumbing system’s durability depends on the quality of its component parts, and the assembly skills of those who install them. Having one without the other ultimately yields an inferior system.

Water source and composition: Today, there are more than 75,000 public water systems in the U.S., and each processes water with singular attributes. Compliance with federal regulations and standards is essential in order to assure safe drinking water. However, inherent features of water, including pH, oxygen content, alkalinity, chlorine, chlorine by-products and even temperature can all affect metallic water pipes to different degrees.
Even the most finely crafted pipes, valves and fittings will not last forever once they are in contact with water. Pinhole leaks form, interior surfaces break down, and rust and other potential contaminants accumulate. Left untreated, these conditions can impede water flow, taint drinking water and cause mold to develop in unseen damp areas.

What to do? For residential and commercial structures alike, some issues can be addressed by fixing a single valve or section of a piping system. If a professional determines that spot repairs are not feasible, there are essentially three options to consider:

Repiping with copper: Copper has remained the conventional piping material of choice for plumbing professionals for more than 70 years, owing to its corrosion resistance and relative flexibility. Today, in fact, copper enjoys a market share of more than 80 percent for new indoor plumbing pipes. Copper pipe is light and rigid—it doesn’t sag over the long run and it requires fewer supports. Manufacturers also offer a 50-year warranty against manufacturing defects, though corroding and associated failures are not covered.

The downside: Repiping with copper usually requires cutting into walls and ceilings. Once work is complete, drywall, tile work and painted areas must be restored. This can prove time-intensive and costly—especially in older buildings and historical structures. Additionally, repiping in older structures often means dealing with asbestos, which increases time and cost burdens.

Repiping with plastic: Manufacturers of plastic plumbing pipes have marketed their products as a more flexible, easier-to-install alternative to copper for more than 30 years. Often, these proponents argue that copper requires a torch to solder pipe and fittings together, while plastic systems employ a solvent cement joining system, thus mitigating potential fire risks during installation. Today, accepted plastics include PVC, chlorinated PVC (CPVC), polybutylene, polyethylene and cross-linked polyethylene (PEX). CPVC and PEX are now approved to all national and most state plumbing codes.

Plastic piping features several inherently good qualities. Yet repiping with plastic still presents many of the same installation challenges as copper repiping—especially in aging multifamily structures. Additionally, critics point out that the solvent-based adhesives used to join pipes actually contribute to air pollution and breakdown of atmospheric ozone. Lastly, PEX has a maximum diameter of two inches, so larger risers and mains must still be repiped with copper piping.

Epoxy lining: Lining copper, galvanized steel, lead, cement and cast iron pipes with epoxy coating offers an immediate benefit of restoring existing plumbing lines without ripping them out. The process uses treated, pressurized hot air to fully dry pipes that are then sandblasted to clean away potentially unhealthy debris and corrosion build-up. Epoxy coating is then blown through the pipe, creating a seamless and sanitary barrier on its surface.

Existing pipes are most often buried within the infrastructure of a building—or in the case of exterior pipes, beneath landscaping and hardscape. Therefore, lining can prove more cost-effective than repiping while also generating less landfill waste. Typical lining installations can also be shorter in duration than repiping projects, since some epoxy products feature cure times that enable water service to be returned, if necessary, on the day of installation. Additionally, epoxy lining can provide protection from future corrosion; the process is less intrusive to tenants; and it protects users from impurities associated with pipe deterioration.

During the past decade, epoxy lining has gained traction among plumbing professionals throughout the U.S., despite the industry’s propensity to embrace traditional products and processes. That said, when opting to use epoxy line, your plumbing contractor should use materials that are formulated for broad-range corrosion protection; they should be certified to meet ANSI/NSF Standard 61, the government’s safety standard for safe drinking water; they should be safe to use in hot and cold potable water systems; and they should be approved for use in pipes where the water temperature can reach up to 180 degrees Fahrenheit.

So which alternative is best for multifamily structures? In a broad sense, you should first consider the state of the existing pipes. Some may be too damaged to be epoxy lined; they must be replaced. Others may retain the structural integrity necessary for lining. The answer also depends on factors relevant to your specific building, from its material composition and layout to the diameter of pipes and their location throughout the structure. You should also account for timing and budgetary parameters, as well as municipal rules governing the renovation of older and/or historical structures.

Regardless of whether problems arise or not, prevention is always a wise strategy. That’s why multifamily owners and managers should have a master plumbing professional evaluate the health and performance of their current plumbing system, diagnose potential issues before they become all-out crises, and suggest appropriate remedies—whether they be spot repairs, repiping or epoxy lining.

Skip Wolfe is vice president of sales and marketing for Beachwood, Ohio-based CuraFlo, a national provider of pipe restoration services for apartment buildings and other multi-tenant, commercial, industrial and municipal structures. For more information, contact 888-4-CURAFLO or e-mail