We are often asked what the "True" thickness of polyethylene (plastic sheeting) means. The plastic sheeting (engineered films) industry is somewhat unique in that lots of terms get used. "True" means that a film that says it is 6 mils in thickness will measure at that thickness of 6 mils by a micrometer. People in this industry understand that most films are +/-10%, so in the case of 6 mil, a 5.4 mil is commonly accepted as 6 mils. When films are reinforced, meaning they have strings running through the film, then the film is often measured at the thickest point, where the reinforcement crosses. Some of these films are as low as 3 mil between the reinforcement grid, yet are sold all day long as a 6 mil film.
There are films that are "true" 6 mil films. One of our films is called, PolyScrim 6. This reinforced film measures at 6 mils. Another example of a "true" 6 mil film is, Anti-Static Fire Retardant 6 mil. It's important to note that plastic sheeting can be made to a multitude of thicknesses to suit the application's needs.
If we look at the terminology behind the thickness of plastic sheeting, it starts with the Greek alphabet. The Greek letter µ when by itself stands for micron. This term has recently been superseded by micrometer or µm. The thickness of plastic (plastic gauge) is expressed in microns. 1 micron = 0.0254 mm =1 millimeter = 1 mil = 1µm.
If you consider the application for the plastic film, now not only does the thickness comes into play but the additives that are added to make the film perform for it's intended use. For example, often people need plastic that is fire retardant- so a 6 mil film won't do the job, unless it is certified as fire retardant. The same goes with whether a film will be in the sun. Without UV inhibitors, a regular piece of plastic won't hold up over time to the sun regardless of the thickness.
There are so many things that go into making an engineered plastic film. Feel free to call us anytime to learn more. Thank you- 866.597.9298
Polypropylene is a form of plastic just as polyethylene is. What separates polypropylene from polyethylene for starters is the fact that polypropylene can be molded in essence becoming pliable above a certain temperature. When it cools it will return to its solid state. Polypropylene can be used not only as a structural plastic, but it can be used as a fiber. It also has a high melting point, which differentiates it from polyethylene. One area where polyethylene has over polypropylene is that polyethylene is more stable. Polypropylene has the advantage that it can take repeated motions such as being a hinge. A hinge made out of polypropylene can be opened and closed many many times, and hold up just fine.
Polypropylene can be combined with other materials, as can polyethylene. Rubber for example can be added, to make it more pliable. One of the exciting additives that is added to polypropylene are minerals. These minerals allow a polypropylene sheet to become a synthetic paper. synthetic paper is essentially plastic paper. It can be easily printed on. It can be folded, hot stamped, die cut, sewn and more. Best of all it is environmentally friendly! All of a sudden polypropylene is transformed into a slew of products. Synthetic paper made from polypropylene is used to make banners, membership cards, maps, menus, phone cards, signs, tags, floor graphics, counter mats, and booklets. The list goes on from here! What is outstanding about synthetic paper is that is is durable, tear and water resistant!
Polyethylene has more demand however than polypropylene. Polypropylene is used extensively in the automotive industry as well as the packaging industry. 70% of the polypropylene uses is for packaging needs for the food industry. It can be made into bottles, food containers, food crates and pallets.
Polypropylene is used to make house wears, appliances and toys. It is also used to make make carpeting and upholstery. The polypropylene is heated and made into fibers. There are so many uses for both polypropylene and polyethylene.
Corrugated plastic sheets are high impact twin-wall plastic sheets that are made from polypropylene copolymer. Think of cardboard that is made from plastic.They are used many different industries for varied applications.Corrugated plastic is also referred to as "fluted Plastic".
Agriculture: Corrugated plastic sheets (fluted plastic sheets) are waterproof, recyclable, re-usable, sturdy and visually pleasing to the eye. Boxes are often made from this product because it is so practical over time.
Automotive: Often the automotive industry is looking for a material that is tougher than corrugated fiberboard yet light, waterproof, and stain resistant. Because of its strength, corrugated plastic sheets are widely used in automotive applications.
Packaging: Corrugated plastic sheets are used all the time in the packaging industry. Due to its design versatility, durability, waterproof feature, and recyclability, corrugated plastic sheets make into wonderful boxes for a variety of products.
Signage and Graphic Arts: Have you seen all those open house signs that real estate agents use to advertise their open houses? More often than not, corrugated plastic sheets are the foundation fore these signs. They allow for consistently high-quality printable surfaces for the verbiage and graphics that go onto signs of all types. They will hold up to rain, stains, and are tough enough to be used time and time again.
Corrugated plastic sheets come in a wide variaty of colors and thicknesses. They can be fire retardant or non-fire retardant.
If you want to learn more about the corrugated plastic sheeting product that Global Plastic Sheeting carries, please click here.
The types of plastic sheeting presented below are "stars of the show" due to their usage. In its simplest terms, the main difference between the different types of plastic is the way their cellular structure, or molecules bond with each other, and how tightly they are formed.
- 1) Low Density Polyethylene (LDPE), most common type of plastic sheeting, very flexible, most often from 0.5 mil thick to about 40 mil in flexible sheeting forms. Good conformability to surfaces. Because the cell structure is not as strong or dense as some other types of plastic sheeting, it is not typically as strong or puncture resistant as other forms or blends, but has thousands of common uses. Widely used for everything from construction and agricultural sheeting (often called Visqueen), Engineered Plastic Sheeting of countless types for such things as Vapor Retarders (also called Vapor Barriers by many), Surface Protection films, Pond and Canal Liners, Covers, Tarps, Abatement Plastic, Containment, packaging, and the list goes on.
- 2) Linear Low Density Polyethylene (LLDPE), blended form of LDPE where the film has much more flexibility, tensile strength, and more conformability. LLDPE is "softer" and more pliable, so is an excellent choice for such things as pond liners, or blended into other films to give them extra strength and flexibility. This is perfect for an application like a self-adhesive carpet protection film, where the film needs to have an amazing amount of strength in a very thin film to absorb impacts, but not tear or puncture. In this form of poly, the molecules all line up and strongly hold together as the film is stretched to give the structure much more strength and elongation than LDPE. Most common in thicknesses ranging from 0.5 mil to 40 mil in flexible plastic sheeting.
- 3) Medium Density Polyethylene (MDPE), the least commonly used form of polyethylene for flexible plastic sheeting. Has more strength than LDPE, a little more chemical resistance, tighter cell structure, more puncture and tear resistance. Often blended with LDPE and or LLDPE to give the attributes one is looking for in a particular type of film. For instance, many pond liners have MDPE to add some strength and toughness, without adding too much stiffness.
- 4) High Density Polyethylene (HDPE, aka HD), widely used for many applications. HDPE is the strongest, toughest, most chemical resistant, and least flexible of these four types of polyethylene. It also has the most UV resistance of the bunch without additive packages to increase this attribute. HDPE has a very tight cell structure, making it very difficult for other molecules to pass through its structure on a microscopic level. HDPE is the most easily field seamed of these products, and is generally used on an industrial level in thicknesses from about 12 mil to 100 mil thick. Most golf course ponds are lined with HDPE, most industrial ponds and canal liners, secondary containment liners, root barriers, many applications where chemical resistance is needed. This is also used in thousands or maybe millions of applications in thinner forms, especially in blends with the other types of polyethylene, because the HDPE adds much strength and toughness with its very tight bonds with other molecules.
The density of polyethylene is measured in a column of water, and they are all classified depending on ranges of density. LDPE (and LLDPE) are generally within the range of 0.919-0.924 g/cm³. MDPE are generally within the range of 0.926-0.940 g/cm³. HDPE are generally within the range of 0.941-0.965 g/cm³. These numbers can vary slightly depending on your source, and are not set in stone, just general guidelines.
The question has been posed whether plastic sheeting is used as a vapor diffusion retarder (VDR). ABSOLUTELY! There are different types of vapor diffusion retarders- but plastic sheeting is one of the primary ways in which to control the moisture content coming into your home or building. A vapor diffusion retarder is a material that reduces the rate in which water vapor can move through a material such as a plastic sheeting liner or vapor barrier. The ability of a material to retard the diffusion of water vapor is measured in units referred to as "perms. Vapor barriers are also measured in terms of its "permeability". Any material with a perm rating of less than 1.0 is considered a vapor diffusion retarder, or a plastic sheeting vapor barrier.
Some plastic sheeting is more effective as a vapor diffusion retarder. That is because it is engineered to specifically retard the flow of water. Additionally these plastic sheeting liners are tested to the ASTM E1745 standard.
To see all our vapor diffusion retarders for crawlspaces, please click here.
Crawl space vapor barriers also referred to as vapor retarders or more accurately-vapor diffusion retarders come with different characteristics to suit the application they are protecting. There are a few fundamental questions that need to be answered so the most appropriate vapor barrier can be selected for the job.
One of the most important questions that arise is whether the home is in an area that has radon or methane gas coming up through the ground. This is critical because radon gas decays into radioactive particles that can get trapped in your lungs when you breathe. This means your lung tissue can be damaged leading to lung cancer over the course of your lifetime. Knowing if you have radon gas in your home will help you decide on buying a crawl space vapor barrier that block deadly radon gas. Click here to learn more about a vapor barrier that retards radon.
The next consideration is the surface to which you are laying the crawlspace vapor barrier (vapor diffusion retarder) upon. It is rocky with sharp rocks, then you need a liner that won't puncture when it comes in contact with the soil. Thicker material will give the crawl space vapor barrier more strength to hold up to that type of surface.
How will you be using the space where you place the vapor diffusion retarder? If it is a crawlspace that is used for storage- or where people will be walking, then again you will want an 18 mil liner that has some brawn.
Please click here to view the various crawl space vapor barriers/ vapor diffusion retarders.
Vapor Barriers also knon as Vapor Retarders, are sujected to a test known as ASTM E1745 to determine if the vapor barrier/retarder will perform well under certain conditions. Vapor barriers have a very important role in the building industry. They are responsible for retarding water vapors that rise out of the earth headed to ruin the flooring above. ASTM E1745 is the standard specification for water vapor retarders used in contact with soil or granular fill under concrete. ASTM E 1745 covers flexible, performed sheet membrane. The values are stated in inch-pound units.
There are three performance classes are outlined A, B and C (with Class A being the strongest). Permeance levels are the same for each class. Tensile Strength and Puncture Resistance change with each class. ASTM E 1745 refers to ASTM E 154 "Standard Test Methods for Water Vapor Retarders Used in Contact with Earth Under Concrete Slabs, On Walls or as Ground covering crawl spaces." These test methods evaluate * Water-Vapor Transmission of Material as Received * Water-Vapor Transmission after Wetting and Drying and after Long- Time Soaking * Tensile Strength * Resistance to Puncture * Resistance to Plastic Flow and Elevated Temperature * Effect of Low Temperatures on Flexibility * Resistance to Deterioration from Organisms and Substances in Contacting Soil * Effect of Low Temperatures on Flexibility * Resistance to Deterioration from Organisms and Substances in Contacting Soil * Resistance to Flame Spread. Standard 6 mil plastic sheeting that has not under-gone any testing in most cases will not hold up over time. It's a lot of work to install a crawl space liner. Make sure you only have to do the job once!
Click here to visit varpor retarders for Crawlspaces, or here for vapor barriers for under-slab vapor barrier applications.
Looking for something a little bit more rigid than flexible plastic sheeting? Here you go...CORREX! Correx is the most versitile product to use for a multitude of applications. Correx is a very lightweight, yet strong and durable. It is made with a twin wall polypropylene sheet material. It is often referred to as corrigated. It is non-toxic, chemically inert, and can be printed on. It can be used for surface protection, or made into boxes, trays, dividers and so much more. It is often used to protect hard wood flooring from heavy equipment passing over it. Some people liken it to plastic cardboard! It can be manufactured in 2mm and thicker.
Correx is very easy to work with. Since it is so lightweight and easy to handle, consumers often cut it with scissors or a knife to fit their needs. It is both water and chemical resistant! It can be fire retardant, and can be made anti-static with U.V. stabilizers to extend its life when out doors.
Click here if you would like to learn more about this wonderful product.
The plastic sheeting liner referred to as LLDPE stands for Linear Low Density Polyethylene. It is a very flexible plastic sheeting product. It is used for making plastic wrap, container lids, toys and stretch wrap. An example in the surface protection arena is carpet plastic. LLDPE plastic sheeting is a perfect poduct to use because the film ca be made very thin (3 mil) and it will still retain amazing strength. Because of its stretching capabilities, it is difficult to puncture.
LLDPE plastic sheeting can have additives added to it to enhance it's purpose. For example, fire retardant additive can be added so that the film is fire retardant. UV additives can also be added to the film with hold up under the sun. The sun's UV rays are a common enemy to polyethylene plastic sheeting. Think of plastic sheeting you see on mounds of dirt that is flapping in the wind. It is usually torn to shreds thanks to sun damage.
If you would like to see a variety of plastic sheeting products made from LLDPE, click here.
The plastic sheeting/ liner referred to as HDPE stands for high density polyethylene. While most think of HDPE as the plastic that food storage containers are made from, HDPE plastic sheeting has many more applications. It is made into geomembranes that can be flexible, depending on the thickness. HDPE is considered one of the varieties of polyethylene. Other varieties include, LDPE (low density polyethylene), MDPE (Medium Density Polyethylene), LLDPE (Linear Low-density polyehtylene) and HDPE. HDPE has many applications because it can be used for projects that require excellent chemical resistance and endurance.
HDPE plastic sheeting can be used for ponds, reserve water storage, canals, landfills, to contain and transport potable water and other liquids, as a waterproof facing for masonry and concrete dams...and the list goes on and on. The geosynthetic industry uses HDPE plastic sheeting to protect the environment. HPDE can protect the environment from petroleum products, hydrocarbons, saltwater, fuel, acids and more. HPDE plastic sheeting is used as a secondary containment liner to collect dangerous liquids from seeping in the ground.
To see some data on HDPE Plastic Sheeting/ Liners, click here.