News

New Replacements for Traditional Materials

By | September 2014

When presenting to my continuing education audiences about the history of vinyl and products made from it, I always like to highlight how often vinyl has been introduced as a replacement for products made of more ‘traditional’ materials. I recently did some research for a book being written by design historian Grace Jeffers which deals with common perceptions about natural and synthetic materials. Her book is not just about vinyl, but about how modern materials can be beneficial in new applications and how they are actually sometimes a preferable choice when compared with earlier materials. I wrote an article a few months ago about the evaluation of ‘real’ and ‘fake’ materials. This is a fascinating topic that Ms. Jeffers introduced in her presentations at NeoCon last year in Chicago.

In life we evaluate situations and make replacements all the time. Health and diet concerns might lead us to choose the apple instead of the apple pie, or to send a simple message we might choose to text instead of waiting for the perfect time to make a phone call. One blog I read recently discussed the creative art of replacement language. The author’s example told about a mom who dropped an iron skillet on her toe; she had to quickly and carefully choose alternative language to express her painful reaction, especially since her kids were in the room when it happened.

In some applications the decision to replace traditional materials with vinyl was driven by outside circumstances and a natural evolution common to advances in material science. Early research on vinyl was prompted by the dwindling supply of natural rubber and in 1926, Dr. Waldo Semon (then working for the BFGoodrich Company) developed what we know as modern-day plasticized vinyl. He took the 19th-century German invention of rigid PVC and made it elastic, resilient and moldable into any shape. Semon found it to be more durable than natural rubber which led to early applications in metal coatings and even shoe soles.

Wire and Cable Insulation

During World War II vinyl saw its first commercial use in wire and cable insulation. At that time, wire insulation was natural rubber covered with a protective woven textile braid. Due to wartime conditions in the Pacific, natural rubber supplies were scarce and material scientists scrambled to find a replacement. Vinyl offered superior durability, electrical insulation and fire safety. The fact that vinyl does not support combustion helped it meet one critical criterion for use in ships and submarines. For these and other reasons it is still the most common wire and cable insulation used today.

Windows

Early window frames were constructed of wood, then later of steel and aluminum. After World War II Europe experienced a huge reconstruction effort coupled with material shortages and in response, vinyl window profiles were introduced in Germany as a replacement material. Early versions of vinyl windows were heavy and bulky, and they were not seen as a preferred replacement in the US market. By 1959, sleeker lines were developed and by the 1980’s vinyl window popularity was on the rise:

Since the first vinyl windows were introduced to North America in the early 1950s, vinyl has continued to gain market share due to desirable physical properties and design versatility. Vinyl windows offer a unique blend of energy efficiency, ease of maintenance and low cost. Today vinyl windows account for 67% of all conventional residential windows sold in the U.S., 27.8 million windows in 2010”.

Data were taken from the 2010/2011 AAMA/WDMA U.S. Statistical Review and Forecast.

Siding and Cladding

Traditional historic homes are usually clad in wood clapboard siding or shingles, or built of load-bearing brick or stone masonry. Wood is subject to water damage and decay if left unprotected. Although deterioration can be delayed through the use of paints or coatings, wood is still susceptible to damage from termites, ants and other pests. Aluminum siding was introduced to the US market in 1937 and it soon became a popular replacement for wood clapboard. However, when the cost of aluminum began to rise and made the product less economical, vinyl stepped in as the new replacement.

“Vinyl siding was first produced in the early 1960s through a process known as profile extrusion. This process was difficult to run at high speeds and to control the final shape, but in the late 1960s a process known as post forming improved vinyl siding manufacturing. In the 1970s and 1980s, the industry made numerous improvements in formulation which have allowed the product to be produced faster, weather better, resist impact, and allow a larger range of colors.

With these improvements, vinyl siding volume grew quickly during the late 1970s and surpassed the volume of aluminum siding in the early 1980s. The advantages of a lower cost material and easy installation have made vinyl siding the single largest residential siding material today.”

Plumbing Pipe

Almost half of all the vinyl resin produced is made into plumbing pipe and fittings. Durability, cost, safety and sanitary concerns are a few reasons why vinyl has become the preferred material for water distribution. Simply put, this is another example of vinyl being the suitable and preferable replacement for earlier materials.

It may come as a surprise that many original water mains were actually made of wood, where long pieces were cut to form a tubular shape and then wrapped with iron rings or wires like a long barrel. Leakage and durability were two common problems associated with this early technology. However, it may come as an even greater surprise that some of these old water mains are still in use.

Water officials say they believe that a handful of wooden water mains are still in use in South Dakota, Alaska and Pennsylvania, among other places. The old wood pipes offer a vivid reminder of the age and fragility of the nation’s drinking water systems, many of which rely heavily on old pipes that often remain out of sight and mind — until they burst.” 

– New York Times 2009

Cast iron pipe was common during the 19th and 2 centuries as pressure pipe for transmission of gas, water and sewage. Cast iron was largely replaced with ductile iron pipe in the 1970s and 1980s.

Asbestos cement (AC) pressure pipe was used primarily for potable water as well as for sewer force mains and industrial effluent and process piping. It was first introduced in North America in the late 1920s and became a common choice for water main construction from the 1940s to the 1970s. Asbestos cement pipe was manufactured from a slurry mixture of about 80-85% portland cement and 15-20% chrysotile asbestos fibers. The use of this material was largely discontinued in North America in the early 1980s but it still represents a significant portion of the water distribution systems in many North American cities.

PVC is commonly used in large diameter pipe for water delivery, sanitary and storm sewers. It has become an ideal replacement for ductile iron, asbestos cement, and copper by providing more durability, corrosion resistance, and ease of maintenance.

The benefits of PVC and CPVC pipe include:

  • No corrosion. The major factor in water main breaks is corrosion. It is estimated that 2.6 trillion gallons of treated water are lost each year in North America due to leaks and water main breaks.
  • Smooth surface delivers cleaner water. Corroded or rough surfaces can collect biofilms and potentially support the growth of biological contaminants such as bacteria and parasites.
  •  Lower resistance to water flow. The smooth interior surface means it takes less energy to push water through the pipe and that means energy savings in water distribution systems. As corrosion grows in a metal pipe the opening becomes smaller and more energy is required to pump water through the system.

For some ‘traditionalists’ the use of newer materials might at first seem unfamiliar. However, after careful evaluation and some serious thinking about health, safety, durability, maintenance, installed cost, and product life cycles, they may find the new replacements to be preferable.

Replacements sometimes start with substitutions; they are based on specific needs. One analogy I like is the basic idea behind the substitution of basketball players that must be done in order to win the game:

“To correctly substitute, one prerequisite is necessary. A coach must know his players– their strengths, their weaknesses, and their condition, both physical and mental. If better rebounding is needed, he must know which of his reserves best meet this necessity. If better shooting is needed, he must know which of his reserves is the most dependable shooter. The same is true if a better defender is needed, or more speed, or better ball-handling.”

– Glenn Wilkes, Former Head Coach at Stetson University

It occurred to me that this is the same situation in building design and construction. It takes many hard working materials to get to the end result. Decision makers always need to evaluate the specific requirements and demands placed on materials and the products made from them, and then make the appropriate choices.