CIM Industries Blog

It’s common knowledge that colder temperatures can impact the curing of coatings. To achieve the optimum performance properties of the coating, special attention to the manufacturer’s application guidelines is needed.

Applications at colder temperatures, or below the manufacturer’s recommendations, require experienced contractors who are familiar with CIM products. 

Coatings fail to bond to concrete for two reasons:   

1. Lack of sufficient surface profile.
2. Moisture in the concrete

Today, most coating manufacturers require concrete substrates to be dry (<5% moisture content) with low vapor transmission (< 3-5lbs per 1000 sq. ft./24 hours) before applying most types of membranes. This applies to both new and existing concrete substrates, although each may have its own set of moisture-related problems. For example, a 90-year-old poured-in-place partially buried concrete tank may face an entirely different set of circumstances from a newly constructed concrete slab with a steel tank mounted on it. Ultimately, the concrete needs to be dry prior to coating.

Aggregates are commonly used in conjunction with liquid applied coatings to provide a combination of the following:

• Protection:
• Light colored aggregates lower deck temperature extending the life of liquid coatings

• Non-skid surfaces:
• For foot traffic
• For automotive and other traffic
• Exit areas for pond, containment, and other sloped surfaces

• Energy costs:
• Lighter colored aggregates will reflect solar energy, whereas dark-colored liquid coatings will absorb heat. Aggregate will reduce coating temperature by as much as 70 degrees on a hot summer day.

• Provides a rough surface in which to enhance the bond of other paints, coatings, and topcoats (asphalt, concrete, tile applications)
• For compliance with ANSI 118.10 IAPMO Approval for applications such as plaza and balcony decks.

Tired of going back to repair waterproofing membranes which weren’t installed properly during the first application?

Time spent planning ahead of time and using proper application procedures can be some of the most important aspects of getting it done right the first time.

Costs associated with repair or “re-do” work can add up quickly. As an example, take a decorative fountain project.

Suppose the installer did not take the proper time and attention into preparing the surface for liner installation. The liner was installed on top of the poorly prepared surface. 

Work continued with the installation of decorative stone on top of the liner. The result:  the fountain looks great, but is it ready to be put into service? Probably not, because important preparation steps were ignored at the beginning.

Environmental conditions can wreak havoc throughout all phases of a coating application.  To maximize the longevity and performance of the coating, we need to monitor environmental conditions, utilize proper testing equipment, and maintain daily field logbooks to stay on the path to coating success!

Environmental Effects on Coatings

Environmental conditions refer to the air and surface temperatures, relative humidity, dew point, and wind speed; each of these can negatively impact the coating if not properly monitored. 

• Air and surface temperatures are the first conditions to check when assessing the potential for effects on the working and curing time of the coating as well as moisture formation on the substrate. It is equally important to verify that temperatures arein line with the manufacturer’s product recommendations. 

 

 

 

 

 

 

 

 

 

 

Experienced contractors know that documenting the activities of a coating, lining or waterproofing application can be the key to a successful job.  The purpose of documentation is twofold:

The first thing that usually comes to mind when people think of profiling concrete to prepare for coating application is sandblasting. Unfortunately, this method may not always be practical. Sandblasting is loud and can create excessive dust so other alternatives are sometimes required.

When applying elastomeric coatings over concrete, abrading the surface is almost always required. This prerequisite to abrading the surface is twofold:

1) Remove the “laitance” or weak surface layer of the concrete.
2) Create an anchor profile for the coating to adhere.

The requirement which most coating manufacturers use to measure the roughness of the concrete surface is the Concrete Surface Profile or “CSP”. CSP was developed by the International Coating Repair Institute (ICRI) and is divided into 10 classifications often depicted by molded rubber comparison chips (CSP 1-10) as shown below.

Polyurethanes are used to make products with properties ranging from soft flexible foams such as memory foam mattresses, to rigid foams used for house insulation. They can be made into soft rubber as used for skateboard wheels or into very hard enamels as used in modern automobile paints.

 The range of properties can be quite wide, just by changing the chemistry a little, but there's a problem. The traditional chemistry uses materials that have an affinity for water. For applications such as fountains, pond liners, waterproofing, water and waste water tanks, roofing — where long term or constant immersion is an essential requirement — that affinity for water will lead, eventually, to the product swelling or even failing. The reason is in the chemistry, itself. Here’s why.

With so many epoxy, latex, polyurethane, polyaspartic and other type coatings  in the market; selecting the appropriate coating to meet your project needs can be challenging.  In deciding between a single part or two part coating it is useful to have a basic understanding of curing mechanisms, coating types, and selection protocols to narrow the choices.   

 

 

 

 

Figure 1: Durometer Chart

There are several methods for testing the hardness of a coating. One common test method used in both field and lab settings is ASTM D2240 – Durometer Hardness. According to ASTM International, Durometer Hardness determines indentation hardness of substances classified as thermoplastic elastomers, vulcanized (thermoset) rubber, elastomeric materials, cellular materials, gel-like materials, and some plastics.