Wall-to-Wall Safety: How Innovative Vinyl Products Protect From Flooding and NoiseTerry Murphy - Sep 2014
The reason architects must be licensed to practice is that they are granted a ‘monopoly’ by the state to protect the public’s health, safety and welfare when it comes to the design, construction and maintenance of the built environment. The state licensing boards require continuing education for design professionals so they will be able to keep up-to-date with current trends and new practices affecting their profession and the public they serve.
The American Institute of Architects (AIA) tracks the learning progress of its members by maintaining continuing education transcripts for them. They are required to get 18 learning unit hours each year, and 12 of those hours are required to be L.U. credits in in the area of Health Safety and Welfare (HSW). This is defined as the testing topics on the Architect Registration Exam (ARE) focused in this important area. As you might suspect, courses qualifying for HSW hours are in high demand because not all courses qualify, and it is sometimes tough for architects to get all their required HSW hours each year.
For many years The Vinyl Institute has responded to this educational need by presenting courses to architects and other design professionals throughout the country. Our progress and development in this area continues, and we have two new courses registered with AIA, both of which are approved for HSW credit.
As I engaged in a conversation recently with AIA about potential HSW topics, I started thinking about safety and how vinyl products play a role. There are many vinyl product applications that contribute to safety. This week I would like to introduce you to a couple of applications that are great examples in this category.
PVC Seawall Systems:
If you have ever spent any time in a coastal area, you are probably familiar with seawalls constructed along the shoreline. They are used to protect structures from storm surge flooding and to prevent damaging coastal erosion. They are also used in floodplain management. Historically sea walls have been constructed from steel, concrete, pressure treated lumber, soil and riprap (broken rock).
PVC is a relatively new material for this application. It was studied and initially approached with some caution by the U.S. Army Corps of Engineers. An interim report issued in 2005 recognized the benefits of PVC seawalls. When compared to more traditional construction methods, PVC seawalls were found not to crack like concrete, rot like wood, or corrode like steel. The material is also resistant to damage from marine organisms and insects.
The Corps report showed promise for vinyl seawalls: “PVC sheet piles are a viable alternative to steel with multiple benefits, but with some limitations. The lower manufacturing cost combined with the lighter weight of sections for easier transportation and handling and reduced size of equipment required for installation translates to a net reduction in construction cost. A secondary benefit of PVC is its non-corrosive nature…PVC floodwalls can be just as effective as a steel system.”
The report stressed the importance of providing UV protection for all exposed vinyl surfaces. It also noted the longevity and durability provided by vinyl. Manufacturers have indicated that these seawall products can last at least 50 years in typical applications. This compares favorably with most other materials used in these applications. Test results on material strength, fatigue, and interlock strength were all noted in the report.
PVC floodwalls are not intended for hurricane flood protection but they would be expected to survive such severe storm exposure. As a matter of fact, when I did a program for architects in San Juan, Puerto Rico on extreme weather, a seawall company I spoke with said that they had experienced no catastrophic failures of their installed sea walls during hurricane Katrina.
PVC Sound and Noise Barrier Walls:
We experience the world in part through sound. But when sound is unwanted it becomes noise. And excessive noise is more than just irritating, it can be a hazard. That’s where sound walls or noise barrier walls come into play. Sound walls are being used in commercial, industrial, transportation, military and roof-top mechanical installations. In researching this topic I have found two different types of systems. One absorbs noise, and the other blocks and reflects it.
The absorption systems work by trapping sound energy in acoustical fiber batts which are enclosed in a PVC shell. Sound energy is conveyed through vibrating air molecules so when the vibrations come in contact with the fiber material it is dampened and absorbed. The product in this illustration is described to have a noise reduction coefficient rating of 1.0, meaning it absorbs essentially all of the acoustical energy hitting the panel, with little to no reflection. Products like this can be used to surround mechanical equipment.
The other type of system, shown in this illustration, blocks and reflects sound energy. I was especially intrigued with this application when I started my research. Highway and transportation barriers make up a small category, but one that is growing as cost and performance benefits are recognized.
I spoke with Dale Gaston, the Vice President of AIL Sound Walls, maker of this system. He sent me a case study done for the Georgia Department of Transportation (GDOT). This installation is along I-75 in Macon, GA. Originally GDOT planned to have steel walls installed on both sides of the interstate highway. Instead, they installed a PVC absorptive wall on only one side saving significantly on cost. This barrier is described as having a STC (Sound Transmission Class) rating of up to 36.
The Georgia’s DOT was also pleased with the fact that the system enabled longer panel lengths to be installed, which in turn meant fewer post holes had to be dug, and less lifting equipment was required. GDOT has specified PVC Sound walls in future projects.
For more information the AIL Sound Walls website.