Positive Responses to Negative Statements About PVC: Part 5

Statement: “PVC building products create poisonous gasses when they burn.”

The facts: This is technically a true statement, but misleading, because it is true about all organic materials (containing carbon), whether natural or synthetic, and there are countless organic materials in every commercial building. The major gaseous products of the combustion of PVC are carbon monoxide, carbon dioxide, hydrogen chloride and water. Chlorine gas is never produced when PVC burns.

But unlike other building materials, PVC is resistant to ignition; most rigid and flexible PVC will not burn without the continued application of heat from another source. The temperature required to ignite PVC is more than 300°F (150°C) higher than that required to ignite wood. The potential for flame to spread from burning PVC is very low because it has a slow rate of heat release, and it does not drip when it burns; instead, it develops a char which inhibits the spread of flame.

When it comes to structural fires, the U.S. Green Building Council’s Technical and Scientific Advisory Committee (TSAC), in its February 2007 report, Assessment of the Technical Basis for a PVC-Related Materials Credit for LEED, admits that there are many sources of toxic gases besides PVC. The report advises that “any firefighter not using a breathing apparatus would be taking on unnecessary risk, regardless of the specific materials present.” There is evidence that – as do many other building materials – PVC may contribute to hazardous conditions in building fires. However, there is insufficient information to determine how widespread or consistent the risks are. The TSAC report goes on to say that “compared with other plastics, and other combustible materials, PVC may have a beneficial role in reducing injuries in structural fires, as it may reduce the chances of a fire igniting or spreading due to its relatively high ignition temperature.”

In our final installment, we’ll look at this statement: “PVC is the largest source of dioxin, the most poisonous chemical on earth.”

Faces of Duro-Last: Darrell Morris

Mid-Atlantic Regional Sales Coordinator
Darrell Morris - Mid-Atlantic Regional Sales Coordinator

Darrell Morris has been with Duro-Last® for nearly15 years with the last five as the Mid-Atlantic Regional Sales Coordinator. Darrell works out of the corporate headquarters in Saginaw, MI. He is responsible for supporting the sales representatives and roofing contractors in his area, which includes Virginia, West Virginia, as well as portions of Pennsylvania, and New York.

Prior to his current position, Darrell started at Duro-Last in production as a shipping clerk. Darrell then worked as a cost accountant/inventory control clerk before becoming a customer sales representative where he assisted customers with their orders and general roofing questions.

Darrell credits his success at Duro-Last to his training in the military. Darrell was active in the Army, Army Reserves, and the National Guard for almost 20 years before he was given a medical honorable discharge. During this time, Darrell served in Operation Just Cause, Operation Desert Storm as well as provided security at the 1996 Olympics in Atlanta, Georgia.

Darrell enjoys the relationships he has built over the years with his sales reps and roofing contractors. “I enjoy traveling to the Mid-Atlantic area and spending time with the different people in my territory,” said Darrell.

One common theme that all employees mention is the family atmosphere. Duro-Last has and always will portray the feeling that you are one of the family.

Factors To Consider When Purchasing A Roofing System: Performance

You must consider many factors when your roof needs to be replaced or when you are constructing a building that requires a new roof: Price. Quality of the product being installed. Prefabrication. Installation disruptions. Ease of maintenance. Performance. Environmental impact. Life-cycle costs, and so on. It is crucial to review all of these aspects in order to make the wisest roofing choice and get the best long-term value for your investment.

This is the sixth post in a series discussing the issues involved in purchasing a roofing system.

Proven Track Record

How long has the roofing system you are considering been on the market? How has it performed? Has its formula changed over the years to improve performance? Is “thicker” really “better” when it comes to roof performance? Answers to these questions are vital to know in order to get the best roof for your building.

Hundreds of roofing systems are on the market today, and sometimes they seem to blend together and appear to offer the same qualities. Not true. Look at how long the roofing product has been around and then evaluate its success. Most manufacturers will be happy to direct you to satisfied customers who can describe how their roofing system solved a problem.

Thicker=Better? Not So Fast!

Some roofing manufacturers promote the idea that when it comes to roof performance, “thicker” means “better.” However, that is not necessarily the case.

Some manufacturers increase membrane thickness by adding more material to the bottom film layer but little to the exposed layer. However, increasing bottom layer thickness does not directly increase membrane performance. Rather, performance is a balance between film formulation, membrane thickness, and reinforcement.

Film formulation determines the flexibility of the membrane and its ability to resist crazing and cracking over time, plus protect against ultraviolet (UV) radiation.

Membrane thickness provides protection from water, snow, and ice elements.

Reinforcement provided by the scrim layer of the membrane is the source of the membrane’s strength. The scrim protects against natural elements such as wind and hail, and from human activities that can cause punctures and tears. Additionally, reinforcement gives dimensional stability to the membrane and strength against building movement.

If you buy or specify single-ply roofing systems, your decision should be based on membrane performance, not thickness alone.

In our seventh installment in this series, we will discuss roofing system features that have a positive impact on the environment.

Is Roofing Part of Your Energy Management Strategy?

Significant Savings Drive Demand for Cool Roofing

Cool Roofing Options and Choosing the Best Cool Roofing System

There are two primary types of cool roofing products on the market today: (1) reflective paints and coatings; and (2) single-ply roofing systems. Paints and coatings based on either acrylic or elastomeric chemistry can be an effective short-term solution for reducing energy costs, but most facility owners looking for long-term, low-maintenance solutions opt for a complete single-ply roofing system.

Many roofing products are on the market, which can make choosing the right one a challenge. Fortunately, several objective tools are available to help with the process. Choosing a system from the approved list of products in the EPA’s ENERGY STAR® Roof Products Program or from the Cool Roof Rating Council (CRRC) ratings chart is a good way to narrow down the selection process. Products on the ENERGY STAR list undergo rigorous testing before approval to ensure that they meet the established standard for reflectance.

In addition, the ENERGY STAR Roof Products Program has developed an energy savings calculator that projects the potential savings from installing a cool roof compared with alternative “non-cool” systems.

Here is a short list of important factors to consider when selecting a cool roofing system:

  1. Reflectance/emittance performance, both initial and after three years.
  2. Long-term track record of durability and performance.
  3. A good warranty backed by a solid, well-established manufacturer.
  4. Climate and weather extremes in a given location.
  5. Maintenance requirements and ease of repair.

In our next installment we will discuss: Single-Ply Cool Roofing Systems


The A Through Z of Associations: Part 4

There are many associations that roofing manufacturers, contractors and other industry professionals can be involved with. Some are technical and engineering-oriented; others are sales and networking associations; and some deal with each of these aspects in the roofing and construction industries.

This is the fourth in a series of posts that discuss associations related to the roofing industry.


The Lawrence Berkeley National Laboratory (LBL or Berkeley Lab) was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

The Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines.

Berkeley Lab developments have resulted in billions of dollars in savings for lighting, windows, and other energy-efficient technologies such as roofing systems.

The lab provides a wide variety of research that is relevant to “cool” roofs and the urban heat island effect, giving building owners important information they can use to select the right roofing system for their building.


Established in 1886, the National Roofing Contractors Association (NRCA) is one of the construction industry’s oldest trade associations and a voice for professional roofing contractors worldwide.

The NRCA offers roofing industry information for roofing professionals, including technical information, special reports, insurance and safety information, and the latest industry news.

The NRCA also provides a wide range of information and services to help home owners and building owners make informed decisions about replacing and maintaining their roofing systems.


Established in 1979 by the NRCA as a separately funded organization, the National Roofing Legal Resource Center (NRLRC) acts as a legal advocate for roofing contractors throughout the United States.

Issues such as contract language, employee relations, regulatory compliance, payment provisions, insurance coverage, and codes and standards can threaten a company’s profitability and even its existence. The NRLRC provides contractors with assistance in resolving such legal issues, ultimately saving them time and attorneys’ fees.