Texcoating Elastomeric Wall Coatings

The use of elastomeric wall coatings is so pervasive today that it is virtually impossible for relative newcomers in the painting contractor business to imagine how we got along without it. The continual problem of moisture penetration has been so successfully addressed by Elastomerics that it is almost a foregone conclusion for contractors to specify its use in any application where moisture is likely to occur.

The Difference is F-L-E-X-I-B-I-L-I-T-Y

The Problem The most serious problems with stucco, masonry and concrete structures are cracks and water damage. These building materials are very hard. However, when a building settles, or is subject to any vibration or thermal expansion...cracking will definitely occur. Because these materials are porous, water can penetrate, causing serious structural damage and deterioration.	The Solution Ordinary house paints are not intended to waterproof or fill cracks. Textured or Smooth elastomeric coating systems produce a flexible layer that seals and bridges cracks waterproofing these porous surfaces with coating. many times thicker than paint. Its superior elasticity provides excellent long-term protection against future cracking.

Product Development

Before texcote elastomeric smooth coat
Interestingly, textured elastomeric coatings haven't been around all that long. Until the late 1950's, there was no such product category in U.S. building construction or renovation. In Europe, however, development of elastomeric formulations for building applications was underway, largely because buildings there are considerably older, and cracking and moisture intrusion problems had become epidemic in the post-war period. At first, manufacturers relied heavily on plasticizers to give them the plastic, water-resistant properties they were seeking. but they discovered problems: While plasticizers made the coating pliable, semi-elastic and waterproof, they often migrated out of the coating after the application, leaving a very sticky surface which resulted in high dirt pickup making it totally unacceptable to building owners. Additionally, after the material had been on the wall for couple of years, the coating began losing its plastic properties, causing cracks to develop and the coating to fail. Resin manufacturers - like Union Carbide and Rohm & Haas - began working in this country to make better raw materials and resin systems which feature 100% internally plasticized acrylics. In 1958, Ivan Morales, a paint manufacturer in Miami, FL, founded VIP Products and, in tandem with the resin manufacturers, began marketing the industry's first line of true elastomeric coatings.

Throughout the next four decades, resin systems technology advanced in quantum leaps, and the resulting textured or smooth elastomeric coating products offered increasingly superior characteristics, particularly elongation, memory and high moisture vapor transmission rates. Today, the use of elastomeric coatings is one of the great success stories in building construction and renovation. Textured Coating, smooth and textured Products, rank among the leaders in the coating needs of the construction industry.

"When properly applied, the use of quality elastomeric wall covering systems texture or smooth is by far the best way to combat the age-old problem of moisture penetration in most buildings.

Gauging Quality

When a job calls for use of an elastomeric wall coating, the contractor naturally wants to select a high-quality products. Generally speaking, there are several criteria found on the data sheets the contractor can use to determine the texcote of choice:

What are the elongation and memory characteristics?
How far does it stretch and can it return from that point?

Some products can stretch to more than 300% to 600% of their size. Look to see if the manufacturer has tested and reported the results of the elongation at their recommended dry film thickness.

What is the volume solids percentage?
What will remain on the surface after the coating has been applied and reaches a full cure?

A 40 - 50% volume solids product is an indicator of a high quality product.

What are the manufacturers recommended wet-mil and dry-mil film thickness requirements?

Properly designed elastomeric coatings can be applied at wet film thickness of 25 to 30 mils. However, the final dry film thickness will be directly related to the volume solids. To achieve a dry film thickness of 10 mils, a 50% solids product would need to be applied at 20 wet mils thickness. To achieve the same 10 dry mils thickness when using a 40% solids material will require a wet film thickness of 25 mils. This must be taken into consideration when estimating material requirements for a project.

What is the moisture vapor transmission rate?

Elastomeric wall coatings must be able to breathe to allow for the transfer of moisture vapor from one side of the coating to the other. Trapped moisture vapor could result in peeling or blistering of the coating. Moisture vapor transmission rates are directly related to film thickness. Comparison of different elastomeric coating moisture vapor transmission values cannot be judged unless the test were all done at the same dry film thickness and the same ASTM protocol. Results are often published in "perm inches," higher numbers are good indicators of moisture vapor barriers.

The longevity of manufacturer can be a key indication of quality as well. The longer a manufacturer has been in business, the more likely that their products are proven to be of sufficient quality for customers to keep coming back. Seasoned manufacturers supply new and innovative products that meet and exceed customers expectations.

Substrates and Climatic Factors

While all exterior building materials are susceptible to expansion and contraction due to climatic changes, concrete and stucco are particularly vulnerable because of their composition and use of dissimilar building materials. Once the water migrates out during curing, the hard material left behind results in a less than flexible surface which shrinks and cracks, leaving the building exposed to moisture penetration. Consequently, textured or smooth elastomeric wall coatings are ideal for masonry, concrete and stucco surfaces.

After texcote elastomeric smooth coat

Textured or smooth elastomerics may be applied to masonry substrates, smooth and split-face concrete block, poured-in-place, precast, tilt wall - or stucco. These surfaces are cracked or inevitably are going to crack. Texcoating textured or smooth elastomeric coatings have the necessary property of lionization that allows them to bridge cracks and stretch up to 600% of their original size. Thermal change can have a tremendous impact on the movement of a structure. What looks like a hairline crack during elevated temperatures can open to three or four times in width when cooled. Quality elastomeric coatings also have the memory which allows them to return to their original size during thermal movement, crack shrinkage or when ground settlement occurs. Textured or smooth elastomeric wall coatings can form the bridge that keeps moisture out.

Concrete and stucco are common substrates for the use of elastomeric coatings, but increasingly, they are being used on other substrates, including brick, metal, EIFS systems, and some types of wood. For instance, elastomeric coatings are excellent materials for waterproofing T1-11 wood siding often used in coastal areas,

The use of elastomeric coatings has been particularly popular in coastal areas of the country when wind-driven rain from the ocean is prevalent. Florida and California are what would be called mature markets for elastomeric coatings, as are other states along the east and west coasts. Home owners in those areas are familiar with elastomerics due to their widespread use.

But elastomeric wall coatings are used in most other parts of the country as well - the Great Lakes area, the Southwest, the Northeast, and mountains. Let's face it, it rains everywhere, and snow in some, this in turn leads to moisture problems anywhere. Damp or wet buildings are difficult and expensive to heat and, left unchecked, can result in extensive interior damage and building failures. Today's painting contractors, architects, contractors, and commercial building owners know the benefits elastomeric coatings offer as a cost effective tool for resolving moisture problems.

Surface Preparation

As with conventional paints, the ability of Texcoating smooth or textured elastomeric coatings to perform as designed depends on proper preparation of the exterior surface to which they are being applied. Coatings manufacturers strongly encourage, without exception, that every new construction substrate should be primed with a quality primer product prior to the application of finish coatings and this holds true when applying elastomeric wall coatings as well.

With older substrates, more thorough preparation may be needed. Most exterior coatings failures - elastomeric and paint and texture coatings alike - result from the presence of contaminants on weathered surfaces. Dirt, dust, grease, oil, rust and chalk should be removed through pressurized water cleaning. Efflorescence may require the use of chemical cleaners, pressure washing and hand tools. Old paint films that are not soundly bonded to the substrate must be removed. The curing stress of a newly applied elastomeric coating can cause old non-adhered coatings to come off. When elastomeric coatings are to be used, contractors are urged to use surface conditioners and primers specifically designed to be compatible with elastomeric wall coatings. For instance, an alkali- resistant surface conditioner is recommended for use on new stucco and masonry to prevent the alkalinity from attacking the acrylic vehicles used in the elastomeric coating. Split-face concrete block can be a troublesome substrate, due to its inherent high porosity. Prior to the application of an elastomeric coating to split faced block substrates surface, a filler coat should be applied. Then elastomeric can be absorbed properly, allowing it to perform correctly.

Also crucial is the use of appropriate sealants at any gaps and joints between dissimilar materials, such as around windows and doors and at any wall penetration for conduits and pipes. While silicone caulks are popular in many common applications, they should be avoided when water-based elastomeric coatings are used. Some silicone caulks can act as a bond breaker, causing poor adhesion. Instead, use of elastomeric caulks is recommended. It is always wise to consult with the manufacturer to obtain its recommendation for the right sealant.

Application Methods

Typically, most elastomeric coatings are still applied with conventional 1" to 1-1/2" nap rollers. More recently, because of advances in application equipment technology coupled with lower costs, more contractors prefer power equipment- airless sprayers and textured spray pumps. "The newer equipment does a fantastic job of getting the material to the wall exactly where you wont it, in a consistent thickness, and with very little waste or overspray, reducing the need for extensive masking".

Because Texcoating elastomeric coatings do not flow like conventional paints, there are challenges for the contractor when applying this material. Elastomeric coatings tend to have a ropey or heavy appearance, after all one coast of elastomeric can equal between 4 to 6 paint jobs.

Aesthetic concerns

Elastomeric wall coverings are widely available in smooth and textured finishes, but contractors are understandably curious about the pros and cons of each. Textured coatings are often used to hide flaws or defects in constructions much like popcorn ceilings in interior residential projects. Small-Aggregate textures can be used successfully without compromising the elastomeric properties. Larger textures sometimes don't work as well. With larger particles, it's like having a piece of dirt stuck in your coating. The film integrity may be compromised.

A gallon of premium elastomeric costs about the same as a gallon premium acrylic latex but because of the required dry film thickness, it takes about 4 to 5 times as much elastomeric to cover the same area. In attempt to cut costs, some industry observers promote the idea of a 50-50 blend of elastomeric and acrylic flat latex. Although this blend will reduce the elongation, memory characteristics, and vapor transmission rate, it has proven to be a cost effective alternative.

Advances in resin systems technology have also made it possible for textured and smooth elastomeric coatings to be offered in a far wider range of colors, and with greater resistance to ultraviolet rays, than was possible even 10 years ago. Still dark colors can be problematic. Elastomeric coatings loaded up with glycol-based universal color are often very sensitive to moisture during the curing phase. If a customer wants a barn red or a hunter green, we remind them that this coating will be susceptible to moisture due to the high pigment loading which slows curing down.

What does the future hold for texcote smooth elastomeric coatings?

Elastomeric coatings are versatile. They provide the aesthetics to rejuvenate weathered and cracked surfaces; they prevent moisture penetration; they last longer that traditional paint coatings; they don't degrade or caulk over time. In other words, they're a great investment. Water-based acrylic elastomeric coatings are designed exclusively for use as a above-grade, waterproofing product. But new uses are possible. Some innovative contractors have found other ways of using elastomeric coatings as a ceiling finish.

For the painting and texcote contractor, who relies on re-application every few years in addition to new jobs, doesn't the use of more long-lasting coatings end up hurting business? On the contrary, Elastomeric wall coatings provide the contractor with new market opportunities with building owners. It can allow the contractor to build a solid relationship with the building owner, maintenance person or manager. Most of whom are looking for assistance to provide on-site maintenance, monitor the coating performance, touch-ups and patch damaged areas. Most importantly, if a contractor supplies a building owner with a product that works better, even exceeds expectations, he's going to have a very satisfied customer, and that means repeat business.

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