Using Proper Field Testing for Waterproof Coatings

32 • IIBEC Interface August 2022
ABSTRACT
This discussion focuses on using common industry testing practices to identify potential detrimental conditions related to the installation of waterproof coatings
on concrete and masonry surfaces. While showing techniques associated with assessment tools and protocols, the presentation will cover a range of topics
related to the installation of various waterproofing materials. Topics will range from evaluating concrete and masonry surfaces prior to coating applications
to proper adhesion/bond testing of a range of waterproofing materials. Case studies will be used to illustrate the importance of these tests in preventing issues
on projects. While the presentation is product-generic, multiple industry standards, protocols, and accepted practices will be discussed and applied.
This paper was originally presented at the 2020 Building Enclosure Symposium.
combined with project mock-ups, can assist in
avoiding costly issues on projects.
INDUSTRY FIELD TESTING
PROTOCOLS FOR SUCCESSFUL
WATERPROOFING PROJECTS
There are many variables on construction
projects that influence the successful installation
of waterproof coatings on concrete and masonry
structures. These range from substrate conditions,
including substrate strength and moisture
content, to installation methods, including application
thickness and surface preparation. There
are many factors outside of material selection
that can have a negative impact on the success of
a waterproofing project. Performing the appropriate
tests in the field and conducting these tests
correctly through proper field testing can better
ensure a successful outcome on our projects.
This paper will outline a few key field tests, connect
the test to material tolerance, and provide
practical guidance in using these test results to
influence decision making in the field and avoid
costly mistakes.
The following paper will be broken down into
three parts. First, it will discuss the importance
of industry-accepted test protocols from industry
organizations such as the International Concrete
Repair Institute (ICRI), ASTM International,
and the American Concrete Institute (ACI). We
Using Proper Field Testing
for Waterproof Coatings
By David Fuller, Technical Manager, International Concrete Repair Institute
CHANITA CHOKCHAIKUL/SHUTTERSTOCK.COM
The discussion will be broken
into two parts. It will begin
with substrate evaluation and
will show the use of the ICRI
310.2R guideline in evaluating
surface preparation methods,
exploring the use of various moisture tests
available, and the conducting of RILEM tube
and pH testing. The second half of the discussion
will cover material installation. Adhesion
testing will be discussed in accordance with
ASTM standards for coatings, repair materials,
and sealants. Finally, the presenter will
describe various methods to determine thickness
of wet and dry coatings. These tests,
August 2022 IIBEC Interface • 33
will next explain how the substrate can influence waterproofing projects and give context to industry tests that help evaluate potential issues impacting a waterproofing material’s effectiveness. We will close with installation problems and how field testing can help remove common installation-related issues.
WHY FIELD TEST?
There are many variables we can’t control on projects, such as unpredicted weather conditions and project schedules. However, some conditions that influence the success of a project we can control. While we may not have designed or placed the concrete substrate, we can ensure that the substrate is appropriate for a waterproofing membrane. While we may not be installing the products ourselves, we can confirm the installation is consistent with the manufacturer’s recommendations. We can achieve this through proper use of industry-accepted field tests. Whether employing the use of these tests during installation, or as part of the mock-up process, it is important to have these standardized tests as benchmarks. Specific information such as location and number of tests required is typically found in the testing protocols and can be included in project specifications as part of an overall quality assurance program.
No matter the product or manufacturer, it is seldom the material’s fault when we look at failures on waterproofing projects. Contributing factors such as the substrate condition, surface preparation, installation techniques, or ambient conditions before, during, and soon after installation can all have a negative impact on the project. Industry-accepted ASTM protocols and testing guidelines from organizations such as ICRI, SWRI, IIBEC, SSPC, and ACI are used to evaluate a number of these influences. We will focus on a few of these tests related to both the substrate and the installation of waterproof coatings.
THE SUBSTRATE
Working as a senior technical manager for a manufacturer, I have evaluated many projects over the last three decades. Most product complaints my colleagues and I see are largely caused by the condition of the substrate. A substrate that is deteriorating, has a high moisture content, or hasn’t been properly prepared can have a high potential for failure when coated with a waterproof coating. Determining substrate moisture levels, preparing the substrate for a coating, and determining the absorption rate of a masonry surface can all be accomplished using industry-accepted field tests.
SUBSTRATE MOISTURE
Surface moisture content, moisture vapor transmission, and relative humidity within a concrete slab can all impact a waterproof coating. It is important not only to understand how field tests determine these real-world conditions, but also to understand the impact each of these conditions may have on a coating.
High surface moisture can impede a material’s ability to penetrate and absorb into a substrate. It can also lead to delamination and improper curing of a material. Most coatings manufacturers publish their thresholds for surface moisture. Typically, these thresholds are somewhere between 12% for certain acrylic coatings and sealers to 5% for non-permeable membranes and overlays. A relatively low-cost surface moisture meter can determine these levels in accordance with ASTM F2659, Standard Guide for Preliminary Evaluation of Comparative Moisture Condition of Concrete, Gypsum Cement and Other Floor Slabs and Screeds Using a Non-Destructive Electronic Moisture Meter. The process involves placing the meter pins down on the tested substrate. Ensure the meter is designed for the substrate that you are evaluating. There is no need for further calculations; the meter will read the percentage of moisture. With this information you can consult with the material manufacturer for the threshold of surface moisture for the selected material (coating). But there are other conditions that we need to understand as well.
ASTM D4263, Standard Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method, has long been a standard moisture test for many non-permeable waterproof coatings. It relies on an 18-in. x 18-in. 4-mil-minimum piece of plastic that is adhered to a prepared horizontal concrete substrate for a minimum of 16 hours. The sheet is then removed, and the surface of the sheet and substrate are checked for visible signs of moisture. This has become a “go/no go” standard test within the industry to determine if a slab is sufficiently dry. If no visible signs of moisture are present, most installers will proceed with installation. But this test does not provide any quantitative data.
ASTM F1869, Standard Test Method for Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride provides quantitative data (Figure 1). For this method, a kit is used to determine the rate of moisture vapor exiting a concrete slab. These calcium chloride kits can be purchased at most commercial flooring vendors. To conduct this test, the substrate is properly prepared and a small cylinder of calcium chloride that has been previously weighed is placed on the floor under a sealed protective cover. The test remains in place for a minimum of 72 hours. After 72 hours, the cylinder is weighed again, and a calculation is used to determine how many pounds of moisture vapor is exiting the slab in a 1000 ft2 (93-m2) area over a 24-hour period. The protocol recommends three tests for areas up to 1000 ft2 and one test per additional 1000 ft2. Most manufacturers will have thresholds for their materials based on this test. If the test results surpass this threshold, then another material should be used.
Another test—and one that has increased in use over the last 5 to 10 years—is ASTM F2170, Standard Test Method for Determining Relative Humidity in Concrete Floor Slabs Using In-Situ Probes. This method involves drilling a small hole, a minimum of 40% of the overall depth of the concrete substrate, and then placing a sensor into the hole. The hole is sealed for a period of 24 hours, at which time the sensor is read using an RH percentage probe also contained in this testing kit (see Figure 2). This provides the percent of RH in the depths of the slab. This value is used to determine the potential for moisture issues in the future. Again, manufacturers will provide thresholds for their materials for this test.
It is important to understand that while these tests are industry recognized, many of these tests are a snapshot in time and cannot account for changes in conditions over time. It is also important to note that these tests measure different conditions, and the material manufacturer or specifier should always be consulted to determine which tests are appropriate for a project.
Surface Preparation
Proper surface preparation is the foundation of any successful coatings project. Improper surface preparation is a leading cause of delamination issues in waterproof coatings. Adequate surface preparation for coatings will offer a sound, clean, profiled, and dry substrate. ICRI 310.2R, Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair (Figure 3), is a valuable, industry-accepted guide that provides in-depth information including the proper tools, processes, surface profiles, and important condition assessments to be made as part of the surface preparation process.
This document will aid in selecting the right surface preparation on a project. Various materials require different levels of
34 • IIBEC Interface August 2022
surface preparation. The document begins with the mechanics of preparation, from chemical treatments to using heavy-impact and pulverization tools. The document also explains micro-fracturing or “bruising” of the substrate. This condition results in small fractures in the upper level of the substrate from using aggressive means during preparation and/or removal. Being too aggressive can result in problems ranging from performance issues with the coating to delamination of the upper level of the substrate due to damage. By choosing the correct tools and/or understanding what corrective action to take if this condition should occur, the guide can help to significantly lower the potential for issues.
The ICRI guide also covers concrete surface profiles (CSPs). The CSP scale measures the roughness or texture left behind after surface preparation. Manufacturers will usually recommend CSPs for their materials. The CSP guide ranges from a 1, which is fairly smooth, to a 10, extremely rough with peaks and valleys over ¼ in. deep. There are evaluation tools covered in the guide used in the field to determine what level of preparation has been achieved (Figure 4). The guide provides insight into what types of coatings require specific levels of CSP, as well as what tools best accomplish these profiles.
A method summary is then offered which discusses each method in detail, including benefits and limitations for each method. The guide closes with a discussion on evaluating surface preparation in the field. This evaluation extends from moisture testing, which we have already discussed above, to various types of adhesion testing and petrographic analysis. This guide is an excellent tool to use to prevent delamination issues in the field.
Substrate Absorption
The last test related to the substrate is testing for the surface absorption characteristics of a substrate. Using a RILEM tube before and after installing a sealer or water repellent can show the effectiveness in the application of these types of materials.
The tests use a straight or L-shaped tube, depending on whether you are testing a horizontal (straight) or vertical (L-shaped) surface. The wide opening of the tube is adhered to the substrate using plumbers’ putty. Water is then added to the tube and monitored. As the water level drops, a volume of water absorbed over time can be calculated, and the effectiveness of a treatment can be confirmed.
Especially in the case of installations of water repellents, the RILEM tube test can offer insight into how well the penetrant will absorb into the substrate and is an important tool to use during mock-ups of these types of materials.
INSTALLATION TESTING
A thorough understanding of the substrate and its preparation is vital to avoiding costly efforts to remove and/or replace materials that have disbonded or otherwise failed due to issues related to the substrate. In this next section we will outline some various adhesion tests that can confirm proper surface preparation and uncover any material incompatibility. We will also cover tests related to maintaining proper coating thicknesses.
Cross-Cut Adhesion Testing
ASTM D3359, Standard Test Methods for Rating Adhesion through Tape Test, can be a valuable tool to confirm adhesion of a waterproof coating on concrete and masonry surfaces, as well as over previously coated surfaces. While D3359 is a qualitative test, ASTM does provide a visual key used to evaluate the amount of coating removed while conducting the test. There are two methods within the protocol.
Method A consists of cutting a 2-in. “X” through the cured, high-build coating (a similar method
Figure 1. ASTM F1869 test kit.
Figure 2. ASTM F2170 test kit.
August 2022 IIBEC Interface • 35
is used to evaluate thin-mil coatings) with a sharp razor knife. A specific tape is then placed through the center of the cuts and rubbed with a blunt object (an eraser works well for this) to ensure good contact between the tape and the coating. The tape is then removed straight off the coating. The X is then visually inspected. The test protocol supplies a grid that is broken down into classifications from 0A, coating removed from the entire area of the X; to a 5A, where no peeling is observed. Coatings manufacturers will provide recommendations of what value should be obtained prior to the installation of their materials. Typically, this will fall somewhere between a 3A and a 5A. (See Figure 5 which is from ASTM D3359.)
Method B, which is recommended for coatings 5 mils and less, uses a crosshatch template to create a grid pattern cut into the coating prior to adhering the tape.
There are several contributing factors that determine test results, such as curing time of the coating and the type of tape used. The coating manufacturer and specifier should be consulted on these critical items. Using ASTM D3359 as part of the mock-up process on any coatings project will help to avoid costly issues related to delamination and coating incompatibility.
Sealant Adhesion Testing
Similar to coatings, it is important to confirm the adhesion of joint sealants on a substrate or under specific project conditions. ASTM C1521, Standard Practice of Evaluating Adhesion of Installed Weatherproofing Sealant Joints, outlines the proper procedure for testing the adhesion of a joint sealant. There are two methods contained on this protocol: a non-destructive test and a destructive test. There are also various ways to evaluate the destructive test which are included in the protocol, but we will provide an overview on the most common practice in the field.
The non-destructive method involves using a blunt instrument at least 1/8 in. (3.175 mm) narrower than the width of the joint. The instrument is used to apply pressure to the face of the joint to be evaluated. While this pressure is placed on the joint, the interface between the sealant and the substrate, or bond line, is observed to look for any areas where the sealant may pull away from the substrate as in Figure 6.
The destructive method shown has two procedures. The first involves cutting through the sealant perpendicular to the joint and making a 6-in. cut down the face of each side, creating a tab. A mark is made 1 in. above the adhered bottom piece of this tab. The tab is pulled at an angle of 90 degrees to extend this 1-in. mark a distance equivalent to the manufacturer’s published movement capability of the sealant. Another method involves cutting a 3-in. tab and pulling the sealant
Figure 3. Guideline 310.2R.
Figure 4. ICRI 310.2R CSP Chip Set.
36 • IIBEC Interface August 2022
Figure 5. Evaluation Table ASTM D3359.
Figure 6. Checking for failure at the bond line using non-destructive method.
sideways (see Figure 7). For more information or to determine which method is best for a project, the ASTM protocol should be consulted. As with coating adhesion tests, sealant adhesion tests should be used as part of the mock-up process before a project commences to ensure compatibility and adhesion to the substrate.
Material Thickness
When applying waterproofing materials, installing within the manufacturer’s thickness recommendations is important. Various issues can arise if these coverage rates are not followed. Moisture-cured urethanes can blister and bubble if applied too thick. Thicker-than-designed applications of vertical coatings can sag on a wall or fail to cure properly. When these same materials are applied too thin, they can result in early failure due to early wear or tear when exposed to movement.
The best method to follow recommended coverage rates is to use the grid system, which calculates how much material is required for a measured area. There is a simple tool that can be used to measure the wet-film thickness of a coating, too. Wet-film thickness, or WFT, is the thickness of a coating as applied wet on the wall or surface. Dry-film thickness, or
Performing the appropriate tests in the field and conducting these tests correctly through proper field testing can better ensure a successful outcome on our projects.
August 2022 IIBEC Interface • 37
DFT, is the thickness of the coating after it
completely cures, and the liquid portion of
the coating evaporates or is used up in the
chemical process.
A WFT gauge is a rectangular device that
uses notches that are marked in mils (a mil is
1000th of an inch) and is placed at a 90-degree
angle into the fresh wet coating. These gauges
can be used for both vertical and horizontal
surfaces, and a typical gauge will range from 1
mil to 80 mils (Figure 8). The gauge is placed
into the wet coating, and the teeth corresponding
to each mil are observed. The last tooth that
shows evidence of wet coating is the thickness
in that particular area.
Combined with the use of the grid method,
using WFT gauges can help prevent
issues related to coating thicknesses on a
project.
No matter the product or manufacturer, it is
seldom the material’s fault when we look at failures
on waterproofing projects. Issues related to
substrate conditions, surface preparation, and
installation techniques can all be minimized
through the use of industry-accepted fieldtesting
practices. Various ASTM protocols,
as well as testing guidelines through industry
organizations such as ICRI, IIBEC, SSPC,
SWRI, and ACI, are used to evaluate a number
of these factors. If these practices are used
prior to the commencement of a project, and
often, during the installation, they can avoid
issues that can become costly once the project
is underway or completed.
Figure 7. Destructive method ASTM C1521 in practice.
Dave Fuller has been in the
construction materials industry
for 30 years and is the
technical director for the
International Concrete Repair
Institute (ICRI). Before working
for ICRI, he held technical
positions for PPG, ICI,
Degussa, BASF, and Master
Builders Solutions. He is a
subject matter expert in coatings and sealers, waterproofing,
flooring systems and concrete repair materials. Using
his product knowledge, he has supported colleagues and
customers with technical insight, site investigations, and
specification development. Fuller has designed, developed
and delivered in person and virtual technical training
programs throughout his career and holds a master’s in
adult education and training.
Publish in IIBEC Interface
10 • IIBEC Interface August 2022
sk any building engineer, management
company, or property owner
and they will tell you that one
or more of the terrace doors
at their property has leaked
at some point during a rain
event. This is a common occurrence, and one
that industry professionals will tell you is “to be
expected.” Exterior doors that experience water
infiltration often result in property damage and
can potentially require expensive or disruptive
repairs. Damage can include minor puddles and
stains, buckling of high-end interior floor finishes,
or even active water leakage into occupied
spaces around and below the door.
While water infiltration at terrace doors can
lead to significant in-service challenges, it is often
a risk that is not given enough consideration
during the design and construction phases.
Even when the design team focuses on door
performance requirements and the contractor
establishes quality control programs during
installation, water leakage may still occur at
terrace doors, particularly at in-swing doors.
Although water leakage cannot always be elimi-
Water Penetration Resistance
at Terrace Doors Hinges
on the Details
By Kelly Cronin, PE; Suzanne Thorpe, PE; and Emmett Horton, EIT
nated, there are preventive measures that can
limit the amount and frequency of water ingress
at and around terrace doors.
This article focuses primarily on side-hinged
architectural terrace doors1 located at upper-level
terraces, balconies, or penthouses as these door
assemblies are typically exposed to more direct
rainwater and higher winds compared with
ground-level doors. However, many of the topics
discussed in this article can be applied to all
exterior doors throughout a building.
THE “INS AND OUTS” OF DOORS
There are many types of doors; they run the
gamut from all-glass to hollow metal doors with
no perimeter gasketing or weatherstripping
to those with more robust, thermally broken
aluminum frames, complete with gaskets and
multipoint locking mechanisms. Doors can be
hinged to open in or out. Often, the architect
of record has a specific aesthetic for a terrace
or amenity area, and the sightlines of the door
play a key role in how the area is perceived or
enjoyed because it serves as the gateway into
and out of the space. For example, an all-glass
door with minimal framing may be desired to
allow a more seamless visual transition between
the interior and exterior environment.
The overall type of door, and the operational
requirements should be carefully considered
when developing specifications during
the design phase. Building code requirements
dictate the direction of operation of the door
(in-swing or out-swing) for occupant egress.
Additionally, performance requirements associated
with, but not limited to, structural capacity,
thermal resistance, air leakage, and water
penetration should be evaluated. For example,
doors that are located at a penthouse-level,
corner terrace with no screen walls or canopies
will experience higher wind loads than doors
that may be positioned at a third-floor terrace,
mid-elevation, under a soffit setback.
Doors can be given a performance rating by
the Fenestration and Glazing Industry Alliance
(FGIA), formerly known as the American
A rchitectural Manufacturers Association
(AAMA). In AAMA/WDMA/CSA 101/I.S.2/
A440, North American Fenestration Standard/
Specification for Windows, Doors, and Skylights,1
18 • IIBEC Interface August 2022
Nearly 22,600 times in a typical
year, fire departments in
the United States respond
to building fires caused by
lightning.1 While this is a
significant number of incidents,
fire is not the most common type of damage
caused by lightning. Instead, the most frequent
type of damage caused by lightning is disruption
of the electronic infrastructure in buildings (Fig.
1 and 2). Specifically, lightning poses a risk to the
electrical and electronic systems that enable us to
perform our everyday and critical tasks.
Lightning is an atmospheric discharge that
releases tens of thousands of amperes and millions
of volts of electricity. When it strikes a
building, lightning can surge through every element
in the building as the energy seeks a path
to ground. If even a portion of that energy passes
through an electronic device, it can melt or shatter
the fine wires, integrated circuits, and delicate
components that control almost all modern
machines, appliances, and systems.
We know lightning damage to electronic
devices occurs frequently. Over 30 million lightning
strikes reach the earth each year in the
United States, causing billions of dollars of damage.
2 In addition to direct strikes on a building,
Six Components that
Will Protect Your
Building Enclosure
and the Electronic
Infrastructure from
Lightning Damage
By Michael Chusid, RA, FCSI, and the Lightning Protection Institute
lightning can enter a building after traveling for
miles over electric power lines, other utilities, or
conductive appurtenances such as metal fences.
Lightning can strike a tree and then side-flash
(arc) into a nearby building. It can even travel
underground to find a grounding point inside
your building.
Immediately, we think of the monetary damage
to repair the structure. Beyond the structural
damage, we need to consider the impact of not
being able to perform business operations or
other essential functions inside of these buildings.
What will happen if a business owner cannot
swipe a credit card? What will happen if the
assembly line is shut down? What will happen
if a lightning strike hits a fire station or police
department—can personnel answer emergency
calls or dispatch first responders?
A lightning protection system can often be a
wise investment. The capital cost of installing a
system is a relatively minor factor in the overall
cost of construction or renovation, and it can be
far less than the cost of the lightning-related damage
and downtime. Fire alarms and sprinkler
systems are installed to mitigate risks; a lightning
protection system offers similar protections for
property and life and should be given the same
consideration.
Moreover, when a lightning protection system
is properly maintained, it can last the life of
a building. And when a structure is demolished,
the metallurgical value of copper, bronze, and
aluminum used for lightning protection components
is partially, if not fully, recoverable.
Without proper assessment of the building
and the function of that building, a lightning
strike can cause structural damage as well as
internal damage to the electrical system that
powers essential equipment. Fortunately, the
installation of a lightning protection system can
mitigate damage to elements of the building
enclosure as well as to the electronic infrastructure
and contents inside.
FUNDAMENTALS OF A LIGHTNING
PROTECTION SYSTEM
A lightning protection system (Fig. 3) provides
multiple paths for lightning to pass safely
through a building—between the sky and
ground—without damaging the building’s structure
or electrical infrastructure, sparking fires, or
causing injuries to building occupants. Highly
conductive copper and aluminum materials used
in certified lightning protection systems provide
a low-resistance path, which safely grounds the
lightning’s dangerous and destructive electricity.
Figure 1. Over 20,000 times a year, fire departments respond to fires caused by lightning.
Figures (1-5) Courtesy of Lightning Protection Institute.
IIBEC Interface journal is seeking submissions for the following issues. Optimum article size
is 2000 to 3000 words, containing five to ten high-resolution graphics. Articles may serve
commercial interests but should not promote specific products. Articles on subjects that do not
fit any given theme may be submitted at any time.
Submit articles or questions to Executive Editor Christian Hamaker at 800-828-1902
or chamaker@iibec.org.
ISSUE SUBJECT SUBMISSION DEADLINE
December 2022 Technology August 15, 2022
January 2023 The Building Enclosure September 15, 2022
February 2023 Decks and Balconies October 15, 2022
March 2023 Energy Issues November 15, 2022
Figure 8. WFT gauge.
David Fuller