LOCATION, LOCATION, AND NO LEAKS!
March 28, 2012 Leave a comment
Be Smarter than Water
By Steve Clark, P.E.
Steve Clark is the P.E. and President of Aquatherm. He is recognized for his award-winning building system designs, international HVAC and piping patents and the knowledge he brings to North America by publishing articles, speaking at events, serving on industry committees and promoting energy efficient pipe alternatives.
If you have been in the real estate game, whether as a developer, owner, architect, engineer, realtor or in maintenance, you have seen one of these; a great building in a great location, sitting empty with a FOR SALE sign. The asking price is too good to be true. Then you get inside and get the rest of the story. Water damage. Mold. Structural damage. Rot. You can’t get out fast enough. But you leave with an uneasy feeling. It seems like an incredible waste. How could a little water cause so much damage? Isn’t water one of mankind’s friends?
Yes, we would not exist without water. In fact we are over 50% water. But the same characteristics of water that make it life sustaining for us makes it harsh on our buildings. Water allows things to grow. Great in nature, but usually not wanted inside of buildings, especially inside of walls and floors. Water is also great at absorbing, transporting and re-depositing minerals. This is also not a good thing inside of wall cavities. So while it is essential to have water serving us in our buildings, it is equally imperative that the water only go where we want it and nowhere else.
This brings us to leaks. Damage from water is the number one maintenance expense for building owners. Some of the leaks come from the outside, from the roof, walls or the foundation. Sometimes the leak (or back up) is from sewer or drainage lines. But according to Terry Smith, Vice President of Engineering and Technical Services for Marriott, International, Inc., the number one source of water damage in their hotels is leaky pressure pipes. While prevent maintenance can reduce leaky roofs and sewer backups, what can a maintenance staff do to keep pressure pipes from failing? The fact is not much. Maybe reduce water velocities where possible (like recirculation lines) and stay on top of the water treatment. But the odds are that most leaks have more to do with the selection of piping materials and joining systems than anything else. So smart owners are starting to take this decision into their own hands. And why not, they are the ones who have to live with it. A leaky piping system can slowly turn a profitable property into an exasperating money pit. A catastrophic piping failure can do this in seconds.
“But I own and am developing millions of dollars of property. I have more important things to think about than pipes!” Try telling yourself that when a water drop hits your head. “But that is the project engineer’s concern.” Engineers specify what is currently commonly accepted practice, because that is the safest defense in a lawsuit. If you want them to specify something that will last longer, you need to tell them. So like it or not, if you want to build buildings that will last, you need to educate yourself on how to specify pipes and fittings that don’t leak. This means understanding where and why leaks occur. In other words, if you want to win at the real estate game, you have to be ….
Smarter than Water
Piping Leaks and Catastrophic Piping Failures
There are two major categories of piping system failures, slow and fast. Slow leaks can go undetected for years causing substantial concealed damage. Having a joint come apart can cause hundreds of gallons to dump in seconds and cause widespread damage. Either failure is expensive and totally avoidable.
There are also two locations for piping failures to occur, in the pipe or at the fittings (This may seem obvious since “What else is there?”). Pipe failures often occur due to a wearing away of the pipe wall from abrasion or corrosion, or due to chemical incompatibility. Fittings fail for a number of reasons including workmanship of the joint, mechanical weakness and/or chemical incompatibilities of materials forming the joint, and other weaknesses in what holds the joint together. Since chemical compatibility is key across the board, let’s start there.
What to look for… As a developer you are used to thinking big. But for now think small. Real small. You are a water molecule. One oxygen atom with two pointy little hydrogen atoms sticking out. And you are crammed inside this pipe with a zillion others. You’re under a lot of pressure in this fast paced world. And you are just looking for your chance to break free. You are literally bouncing off the walls when you see your chance, an unprotected metal molecule dead ahead. So you aim your right hydrogen atom at that already weakened bond and bam, you are one step closer to being free. And every molecule of water in pressure pipes seeks freedom.
Think this that is a little overly dramatic? Actually there is a lot more excitement going on inside your pipes than you know. Try walking in a crowd and doing a 90 degree turn in a 2-inch radius. For us this world is out of sight and out of mind. At least until it is dripping from the ceiling.
Chemical inertness of piping materials
The term “water” covers a wide variety of liquids ranging from deionized water to Dead Sea Water. PH levels and entrained oxygen vary widely. In order to last in the real world all materials exposed to water must be extremely inert.
Steel Pipe. Have you ever seen steel pipe on its way to a job site? Well the brown stuff on the surface is called rust. It is a breakdown of the metal caused by water and air. Take it as a big red warning flag that this material is not compatible with water.
Copper Pipe. Bare copper is also susceptible to attack by air and water. However, in most wet conditions copper does not stay bare. A thin film of microbiological growth forms on the copper and protects it from the water. At least that has worked until recently. Modern water treatment techniques are now such that they kill growth of micro slime in the piping system. So the copper atoms are just hanging out there as the water ions go wiping past, pulling them away. This is one reason why copper pipes just don’t last like they used to. And those copper atoms end up in your drinking water.
CPVC – This plastic material is very inert to water and to chlorine (it is 2/3 chlorine). But since it is bonded together using chemicals, it has to be very sensitive to some chemicals. Unfortunately, many of these chemicals are found quite normally in the real world of a construction site. For example POE oils are used in nearly all HVAC systems. A trace amount of these oils in a CPVC pipe system and within hours there will be pinhole leaks throughout. Two recent examples of complete system failures caused by this are a senior living facility in Florida and a new college in Kentucky. Do the CPVC manufacturers stand behind their product in these cases? No. They publish a short list of materials that will not hurt their pipes. If one of the thousands of materials not on the list touches it and it fails, tough luck.
Polyethylene – This is made of long chains of hydrocarbons that make it difficult for the water molecules to find a weak point. This makes it more inert to water.
Polypropylene – This is also made of long strings of hydrocarbons, leaving no opening for weakness. In fact PP is so inert, it is the preferred pipe for use in acid waste systems for chemistry labs. That is about as abusive of environment as there is.
Gasket Materials – The idea of a gasket is to keep water from leaking out of joints by squeezing a softer material between two rigid surfaces. Guess where the water will attack? It is not a matter of if the gasket will fail, the only question is when.
Strength. And Flexibility. Pipes take a constant beating, from inside and out. Their need for strength under pressure is why mankind had gone to metal. But modern plastics can now provide the needed strength at a fraction of the weight, and without the downsides of metals. One downside of metal is its lack of flexibility. Think about what happens when the temperature drops below freezing. As water freezes, it expands with incredible force. Metal and CPVC systems usually fail under this condition, while polyethylene and polypropylene piping materials can usually absorb this expansion and return to shape when the water is melted.
What to avoid…. Every time you add another material to the system you add more failure modes. There will be compatibility chemical issues between the new material and the other materials as well as the fluid.
Joining System – Often the weak link
Look for structural integrity
A pipe joint can be constantly exposed to a ton of force trying to rip it apart every second it is in operation. Water surges or water hammer can greatly increase this. Yet unfortunately, the joining system is often the weak point in many piping systems. If the joining system looks less secure than the pipe itself, avoid it. If the joining system is counting on mechanical components like clamps or crimps that can come loose, then steer clear. Remember, if something can work itself loose, it will.
A special case of this structural issue is the dry fit. Some plumbers and pipe fitters mock up the job first, and then come back and glue, solder or compress the joints. On occasion they miss one, and it can hold for some time before there is a catastrophic blow off. You may want to avoid this style of connection.
The best thing to look for is a joint that is welded or fused together using the same material as the pipe itself. If this type of joint is made thicker than the pipe wall, the joint will no longer be the weak link.
Look for a leak path
The water will be looking.
Cut a fitting in half and look at it from the water’s point of view. Is there a way that a very determined H2O molecule could work its way out? Could it eventually work its way through the threads, the gasket, solder, or glue? Water is determined, patient, and hard working. Remember the Grand Canyon.
Examples from other owners
What do domestic hot water piping for King County prisons in Washington, the chilled water piping for Fort Hood Army Base in Texas, water-source heat pump piping at the University of Maine, fan coil (hot and chilled water) piping serving a Florida retirement home, process piping at an Idaho milk factory, and compressed air piping at a Rocky Mountain titanium plant all have in common? Two things:
- The choice of piping materials was extremely important to the owners or administrators of these buildings.
- After rigorous evaluation of the material options, the decision was made to flat spec Polypropylene-Random (PP-R).
The driving factor on these projects was the need for a long-term, reliable system. Cost was secondary. This is a radical change in an industry not normally known for radical change. Most owners in North America would be well served to become familiar with this piping system option.
As a building owner or developer, you can’t afford to be nonchalant about what piping system goes in your building. You have too much invested to let a water leak destroy what you have built. This is not a decision to leave to the low bidder. Even your engineer needs you to weigh in on this decision. So do some research and ask questions. Be “Smarter Than Water.”