Building-Exterior Prep Tips for Protective Coating

MONDAY, JUNE 1, 2020

By APV Engineered Coatings

The process of properly applying a protective coating to a building’s exterior is more complicated than it might seem. Simply pressure-washing the facade and then painting it is not enough. Meeting the manufacturer’s surface preparation and coating environment requirements for the system is the key to achieving high-quality, long-lasting results.

According to NACE International, 75% of all premature coating failures are caused by improper surface preparation. This is why experts at APV Engineered Coatings work in concert with carefully chosen certified contractors to closely monitor surface preparation before the company’s system, NeverFade Restoration Coatings, is applied.

APV is involved in assessments every step of the way to ensure the process runs smoothly. PHOTOS COURTESY OF APV ENGINEERED COATINGS


Complete a careful pre-coating inspection.

Coating failures are often caused by improper initial assessments. Whether a structure is old or new, in need of repairs for problems like blistering, peeling or pinholing, or receiving its first coating, it is important to involve the coating manufacturer from the outset. Often, APV works not only with its certified contractors but also with engineers and general contractors on the project to assess the surface conditions of the property.

  1. First, we identify the type of substrate that needs coating and the existing coating system, if there is one.
  2. Structural and other underlying issues are addressed. For example, metal surfaces are tested for environmental contaminants like chlorides, sulfates and nitrates — which need to be removed, if present.
  3. A mock-up installation or smaller portion of the surface is prepped and coated, sometimes using multiple methods or surface profiles, such as hand abrasion, mechanical tool abrasion and blast abrasion, or additional primer and sealer products.
  4. Adhesion is tested, and then NACE, SSPC, ISO or ASTM standards are incorporated into the guide specification to dictate how the surface should be prepped for coating installation.

A detailed assessment of the surface in question, as well as the environment in which it exists, is crucial to the success of every project.

Consider environmental factors.

Assessing the environment is also crucial to the success of every project. Prior to applying a coating, it is critical to measure and record climate conditions like relative humidity, air temperature, surface temperature, dew-point temperature and the difference between surface and dew-point temperatures. Those conditions, which vary throughout the installation, dictate whether and when a coating can be applied.

Coatings applied in poor environmental conditions can risk the performance of the coating installation and negatively impact life cycle. Curing ability, lay-down/aesthetics and dry film thickness (DFT) or coating thickness — which is arguably the single most important measurement made during the application and inspection of protective coatings — are impacted by climate. Coatings are designed to perform their intended function when applied within a tight ambient climate and DFT range, as specified by the manufacturer.

Make sure the primer complements the coating.

It is essential to pair a primer with the right topcoat, which is easier to do when the coating manufacturer is consulted on product features. APV offers three complementary primer systems — a universal primer (W-1500); a bonding primer (W-1650), intended for coated surfaces that are tough to adhere to, such as Kynar 500 and other factory coatings; and a low-VOC, two-component, corrosion-resistant epoxy for use in coastal areas or abrasion-prone environments. The company also custom formulates primers for unique substrates or environmental conditions.

NeverFade coatings come in three main topcoat formulations that incorporate Kynar Aquatec — the PVDF polymer engineered by Arkema — into the binder. NeverFade Original is for wood, masonry, stucco, fiber cement, EFIS and concrete. NeverFade Metal Restoration is used on all types of ferrous and non-ferrous metals. NeverFade 2K Performance Topcoat is a crosslinked technology that offers additional durability on a variety of surfaces where greater chemical and abrasion resistance is required. All products are dispersed in water, which keeps VOCs low and air quality high.

Set yourself up for success.

Ultimately, if you’ve done a thorough pre-job assessment and selected a knowledgeable contractor that works directly with the coating manufacturer, issues should be minimal to nonexistent. Once surface preparation is completed properly, the most important consideration is knowing you have sourced the right coating system.

It’s important to recognize that there is no one-size-fits-all paint. Every job is unique. To lengthen the life of any building material, a complete and robust solution designed with a trusted source is essential.

“When a customer chooses NeverFade for their project, they are sourcing a solution that is going to increase the life cycle of the facade, so we want to make sure they’re getting what they’ve asked for,” said Michael Couchie, Vice President, APV Engineered Coatings.

The components of the coating can tell you a lot about how it will perform. In the case of NeverFade systems, the resin binder and pigmentation, polyvinylidene fluoride (PVDF) and complex inorganic pigments are its most valued features, designed to outlast other high-performance coatings in their class, including 100% acrylics, two-component urethanes and certain other fluoropolymers, such as FEVE.

For more information, visit NeverFadeCoatings.com.

Claims or positions expressed by sponsoring authors do not necessarily reflect the views of TPC, PaintSquare or its editors.
NeverFade® is a registered trademark belonging to APV Engineered Coatings, Inc. Sold under a trademark license from Arkema, Inc., the owner of the Kynar Aquatec® trademark.