Types of elastomeric coatings and uses

The Many Types of Elastomeric Coatings and Uses of Them

The types of elastomeric coatings and uses of them are numerous. Here you can learn a little bit about each type and the purposes for which they are most often used.

Elastomeric Coatings

Elastomeric Coatings

Modified Asphalt

A modified asphalt coating consists of asphalt and rubber-like polymers. This material is most often used on roofs, although there are a few other applications. It is not suitable for sealing driveways or for covering other asphalts, as it does not adhere directly to asphalt.

There are several disadvantages of this material. It is only available in black, which absorbs and transfers heat, making the building hotter if it is used on the roof. Softening and deterioration occurs over time due to exposure to solvents, grease and UV light.

Polyurethane

There are several categories of polyurethane coatings. They are used to cover spray-foam, wooden decking and other building materials. None are exactly waterproof, although they do help to prolong the life of wood by preventing rot.

Aromatic polyurethanes are one type. The disadvantages include discoloration and chalking over time. They are often used as a base coat for other polyurethanes, although when used as a final coat, the appearance is initially pleasing. Modified and single component polyurethanes are also available.

Silicone

Silicone types of elastomeric coatings and uses are limited. They are recommended in situations where “breathability” is desired. Moisture vapor can pass through the coating.

Silicone is not compatible with other materials. For example, an EPDM coating will not adhere to silicone. Since the coating allows the passage of water vapor, it is not recommended for roofing or similar applications.

Neoprene

Neoprene is a type of synthetic rubber made by DuPont. The coating is fast drying and retards vapors, but a top coat is required when the coating is used on exterior surfaces. Thus, there are numerous limitations to types of elastomeric coatings and uses of them.

Hypalons

Hypalons are another type of synthetic rubber also made by DuPont. The Hypalons have more applications than the Neoprene material. They can be used as fire retardant and waterproofing agents. They are often used in roofing and for coating tanks and coolers.

The Hypalons are compatible with other coatings and can be used on top of many of them, but it is necessary to check with the manufacturer about that.

Butyl Rubber Types of Elastomeric roof Coatings and Uses

Butyl rubber is the most water resistant coating, which makes it a good choice for applications that are very wet or very cold. The coating is often used in coolers, freezers and cryogenic storage units, water storage units, ponds, pools and roofs.

There are limitations of this type of coating. It can be damaged by hail, foot traffic or flying debris. It has a tendency to become chalky and is more sensitive to weather than some of the other options.

EPDM

EPDM is yet another type of synthetic rubber. It has the widest range of applications and the highest compatibility with other materials. Only asphalt and silicone cause problems with adhesion. The coating can be used on those surfaces if an undercoating is used.

Flame retardant materials can be added to EPDM if fireproofing is desired. The UL listing on the manufacturer’s label will reveal the fire resistance of the coating.

EPDM is often used in roofing as a waterproofing agent. It is long lasting when exposed to weather and can serve as a top-coat with no additional treatment. EPDM is among the best types of elastomeric coatings and uses of EPDM are nearly unlimited.

THINGS TO REMEMBER WHEN USING LIQUID RUBBER

1) Catalyst must be added prior to use. Scrape sides of container with a Liquid rubber spatula to ensure catalyst distribution.
2) Xylene or Mineral Spirits Solvents may be added to adjust viscosity or for clean-up.
3) Easiest way to spread the rubber on a flat surface is to broadcast material with a rubber squeegee then roll using a short nap roller. Product is self leveling. A flat spatula can be used for small areas.
4) Product has a long pot life after catalyst has been added; 4-6 hrs. depending on temperature.
5) Only temperature affects the rate of cure. Relative humidity has no influence.
6) Product is hydrophobic (sheds water) so substrate to be coated must be dry initially. The uncured rubber can get wet or even have ponding water, with only a cosmetic effect after application, and will still cure.
7) The rubber will penetrate into porous substrates such as wood and poured concrete. A primer/sealer should precede application of liquid rubber.
8) The chemical reaction of the catalyzed rubber can be arrested by freezing the material. This can keep material usable for weeks or months. To use again simply allow it to reach room temperature and apply.

How to Maintain Your RV EPDM Roof

With proper care and maintenance, your RV EPDM roof can last for 20 years or more. That’s pretty much equivalent to the life of the vehicle itself. One of the benefits of EPDM Rubber roofing materials is that the care and maintenance required is minimal. Regular cleaning is the first step.

Most manufacturers recommend cleaning the roof at least four times per year. The cleaner used should be one that is specifically designed for EPDM roofing and is free of petroleum distillates.

Products containing petroleum distillates, whether they are designed for cleaning or protecting, will cause the rubber to swell and loosen. There are many chemicals that fall under the category. The easiest way to tell for sure that the cleaner you are using does not contain any of the chemicals is to look for one that states on the label “free of petroleum distillates, safe for use on RV camper rubber roof.”

Cleaning is a relatively simple matter, but you should keep your safety in mind. If you are going to be getting up on the roof, you should be on your hands and knees to reduce your risk of falling.

The first step is to rinse the roof thoroughly with plain water at a relatively high pressure. Any branches or sharp objects should be removed by hand, if possible. While EPDM is tear resistant, sharp objects can cause scratches when they are pushed along the surface. Eventually the scratches can become tears.

Once all debris has been rinsed away, you will need to take a medium bristle brush, a bucket of safe cleanser diluted with water and get up on the roof. You need only scrub in areas where you see stains or dirt.

Keep your hose with you so that you can rinse while you are cleaning. Start in the corner farthest away from your exit point and work backwards to minimize the amount of time you spend on the wet surface.

After the roof is cleaned, you can use an EPDM protectant if you like. The protectant should be specifically designed for EPDM roofing, not for other types of materials. Some EPDM manufacturers also sell special protectants. While using the protectant is not essential, it may extend the life of the roof and reduce your need to restore or repair the roofing material.

Finally, proper care of your EPDM roof includes parking it in an area where the roof is protected as much as possible. Don’t park around fruit trees. The citric acid can deteriorate the material in between cleanings.

Liquid EPDM and its benefits

The EPDM roofing association which started in 2002 has always focused on educating contractors and the roofing community on the characteristics and benefits of EPDM membranes. Their studies have concluded that EPDM’s service live is over 20 years. Arguably the most important benefit of an EPDM system is the membrane’s flexibility. A growing number of contractors are specializing in EPDM installation, due to its low callbacks and insurance premiums. EPDM roofing systems also feature low maintenance, easy repair options and low annualized costs.

With Liquid EPDM there is No cutting, No gluing and No Seaming! EPDM Liquid Rubber® totally eliminates the problems encountered with single ply materials because it produces a seamless membrane which is all of the same chemistry. So what do we gain by using EPDM Liquid Rubber®? It eliminates seam failures and eliminates shrinkage of the single ply rubber. It also prevents further chalking particularly with white EPDM and it extends the life of a roof. Liquid Rubber®, available through Epdmcoatings.com is the only EPDM in Liquid form. This product is a high solids solution of sheet EPDM Rubber. It converts from liquid to solid elastomer via a unique free radical cure mechanism which works at temperatures of 55° F and higher. EPDM Liquid Rubber® can be applied directly on many types of substrates that have solid, stable, non-porous and uniform surfaces such as flat roofs. For most substrates, primers are not necessary. As an example, some types of substrates that can be coated with EPDM Liquid Rubber® without a primer are:

• EPDM Rubber Membrane on flat or sloped Roofs
• Weathered Steel Siding
• Outstanding barrier for salt-water environments
• Weathered Fiberglass
• Weathered standing seam and corrugated metal roofs
• Weathered Vinyl, PVC and Polycarbonate plastic
• Foam insulation for pipe
• Cast Concrete foundations

Liquid Rubber® may be applied at any temperature that permits it being spread onto the surface. It will waterproof immediately upon application. The solvent will evaporate at a rate governed by temperature but will not be affected by relative humidity. Exposure to freezing temperatures before cure has taken place will not damage the film. The time necessary to reach cure should not be a concern as this process will occur automatically. Exposure to sunlight will accelerate the curing process. The final film properties of the cured membrane will be the same regardless of the time required to achieve cure.

EPDM Liquid Rubber® will provide long term protection even under extreme exposure conditions. It is resistant to temps of 300 degrees F and minus 62 F. Liquid rubber is water resistant even in an uncured state. An unexpected rain shower shortly after application will not wash it off. The slow cure and non-polar nature of EPDM Liquid Rubber® gives it outstanding surface wetting properties. The product does not fill cracks and crevices but will produce an even film penetrating even the smallest surface irregularities. When EPDM Liquid Rubber® is applied over porous surfaces such as poured concrete, pinholes will appear on the surface as the material slowly displaces the air in the pores. This surface wetting feature enables the product to be applied in a SINGLE COAT and the still results in complete film integrity. EPDM Liquid Rubber® can be applied to hot surfaces encountered during the summer. The solvent in the system will flash off rapidly but the polymer will remain soft long enough to permit overlapping even after 1-2 hours. The cure rate is still controlled even at temps up to 120 degrees. The product can, therefore, be applied on the hottest day.

The controlled cure rate also results in a longer pot life, giving the applicator more than adequate length of time (4-6 hours depending on temperatures) to use the mixed quantity of material. Adhesion will increase over time. Polar surfaces such as metal, concrete and wood result in stronger adhesion than non-polar surfaces such as asphalts. Most weathered surfaces including single ply and thermoplastic membranes will have enough of a surface profile to anchor the EPDM Liquid Rubber®

By itself, the EPDM Liquid Rubber® membrane will exhibit the characteristics of its EPDM chemistry i.e. U.V. ozone stability, excellent ponding water resistance and long-term retention of flexibility. EPDM Liquid Rubber® applied over generally sound singly ply EPDM can extend its life another 20 years. The useful life of metal roofs will also benefit greatly when EPDM Liquid Rubber® is applied. It is recommended that a corrosion inhibitive primer first be applied to areas where severe rusting has occurred. EPDM Liquid Rubber® does not contain any corrosion inhibiting pigments but it is such an effective moisture barrier that it can be applied directly over light rust without a primer. For more information contact EPDM Coatings or call at 855-281-0940. They also have a blog filled with discussions from customers as well as valuable information on the product at http://liquidroof.blogspot.com/