Elastomeric coatings’ flexibility and durability make them ideal for repairing cracked stucco, waterproofing concrete structures, and providing a fast, economical way of improving a building’s aesthetic—but using the wrong type may cause unforeseen problems for contractors and building owners alike.
With countless varieties on the market today, how do you choose the right one? Here are some key considerations to keep in mind before selecting an elastomeric coating for your next job.
First, the basics. What are elastomeric coatings?
Elastomeric coatings are thick, durable, water-resistant membranes engineered to flex and move with the underlying surface.
Elastomeric refers to the elastic, rubber-like properties of the polymers (known as elastomers) in the coatings. These elastomers give the coatings their signature flexibility, which allows the coatings to stretch and bridge hairline cracks common in concrete, stucco, and masonry surfaces.
Elastomerics can be up to 10 times thicker than paint and provide a durable, long-lasting barrier that prevents water and other contaminants from entering exterior surfaces through cracks caused by freeze/thaw cycles, settling movement, and physical impact.
Same product name, vastly different results
One misconception we often hear is that all elastomeric coatings are the same. The truth is, all elastomeric coatings are not created equal. While the term elastomeric is widely used, a broad standard is applied.
Open any two competing products’ data sheets and you’ll see a wide range of standards featured throughout. As Figure 1 shows, coating manufacturers are inconsistent with the properties they test and the test methods they use, which makes it nearly impossible to compare products using data sheets alone.
Unlike other building materials, no standards were developed for elastomeric wall coatings, prompting manufacturers to adopt and modify standards established for other products. This can lead to further inconsistencies and product variations if manufacturers modify tests in different ways.
As a result, there’s a diverse array of elastomerics on the market today with equally diverse properties and performance results. Some coatings are waterproof; others are dampproof. Some are breathable while others trap moisture. The variations go on—and if you choose a coating based solely on the elastomeric name, you could run into problems.
Common issues with underperforming elastomerics
Every job is different. There are different substrates, environmental factors, and performance requirements to consider when choosing an appropriate coating. Failing to take these factors into consideration when selecting an elastomeric coating could lead to some of these common issues:
Peeling – Thin, low-quality coatings don’t have much hiding power, so a thicker application is required to achieve the desired look. This limits breathability and traps moisture, causing the coating to peel.
Bubbling – Some elastomeric coatings are not breathable, which causes moisture to collect in the substrate. Since elastomeric coatings flex and stretch, the pressure from the trapped moisture causes the coating to expand like a balloon. This bubbling effect can retain water and prevent moisture from escaping in vapor form.
Cracking – Using an elastomeric coating with minimal elongation will cause it to crack (rather than flex) as the building moves. Once the coating cracks, peeling is sure to follow.
Leaking – Some manufacturers produce elastomeric coatings that are not waterproof. Needless to say, if you use one of these coatings to solve water issues, leaks could result, requiring you to recoat with another product or apply additional coats (which brings us back to the breathability issues mentioned above).
Maximize performance and breathability with Conproco Lastic
If you’re looking for an elastomeric coating that maximizes breathability and waterproofing performance, we recommend trying Conproco Lastic.
Lastic is a highly flexible, waterproof coating that helps to prevent water and contaminant entry by bridging hairline cracks in concrete, stucco, and masonry surfaces.
Engineered for optimal performance, this tough, breathable coating has long been the choice of building owners who demand a superior waterproofing membrane and extended life protection.
What sets Lastic apart
Technically speaking, any material with a perm rating greater than 1 is considered “breathable”, so if vapor permeability is a concern of yours, then you may want to understand just how breathable your coating really is. Lastic boasts a rating of 39(!) perms at a dry film thickness (DFT) of 15 mils., making it one of the most vapor-permeable elastomerics on the market today and an excellent choice for brick and other masonry surfaces.
Moisture vapor transmission Method B wet cup
16.2 perms @ 15 mils. DFT
39 perms @ 15 mils. DFT
Did you know? Some manufacturers don’t list the DFT tested because they can achieve higher perm ratings with thinner coatings.
Many competitive elastomerics don’t pass ASTM E514, the Standard Test Method for Water Penetration and Leakage Through Masonry, which determines whether a coating is waterproof. Competitive products that cannot pass this test are less resistant to water and are often listed as dampproof instead of waterproof—and may cause leaks.
No primer required
Unlike competitors’ products that require a primer and multiple coats, Lastic requires no primer, saving you time and money on product and labor costs.
Vibrant, high-quality colors
Available in 38 standard colors and unlimited custom colors, Lastic uses the highest grade of Titanium Dioxide (TiO2) for brighter, colorfast colors. Other manufacturers use lower-grade products to cut costs, which can result in dull colors that fade.
Lastic uses high-grade elastomer components while competitors dilute their elastomeric coatings with limestone fillers to cut costs. These cheap fillers lower the elongation ratings of competitors’ products, which can cause cracking.
Ready to give Lastic a try?
Contact us to get started.