Fun Fact Friday: EIFS Inspections

Fun Fact Friday: EIFS Inspections

One of the many services offered by Encorus Group’s Civil Materials Testing & Inspection Group is EIFS inspections. According to ASTM international, EIFS, or Exterior Insulation and Finish Systems, are an exterior wall system that consist of an insulation board attached to the substrate, a base coat, and a protective top coat. These systems offer constant insulation, and allow architects to design buildings without the added concern of choosing materials for insulation purposes.

EIFS were originally only used on commercial buildings, but have found their way into residential buildings as well. According to the EIFS Industry Members Association (EIMA), EIFS generally consist of:

• A water-resistive barrier (WRB) that covers the substrate
• A drainage plane between the WRB and the insulation board that is most commonly achieved with vertical ribbons of adhesive applied over the WRB
• Insulation board typically made of expanded polystyrene (EPS) which is secured with an adhesive or mechanically to the substrate
• Glass-fiber reinforcing mesh embedded in the base coat
• A water-resistant base coat that is applied on top of the insulation to serve as a weather barrier
• A finish coat that typically uses colorfast and crack-resistant acrylic co-polymer technology
EIFS claddings are becoming increasingly popular due to their energy savings and reduced environmental impact. EIFS can reduce air infiltration by up to 55% compared to wood or brick cladding. In addition to this, EIFSs are durable, aesthetically flexible, and are fire resistant.

Most EIFS do not have drainage systems, therefore if the moisture level becomes high enough, the substrate is subject to rotting, leading to the failure of the EIFS. According to the American Society of Home Inspectors (ASHI), there are several things to look for when examining an EIFS for moisture damage. Things noted by the ASHI to observe visually include, dark streaks at the bottom corner of the windows and where the ends of the gutters meet, obvious signs of physical damage such as dings or holes, and exposed mesh, the EIFS touching the roof shingles, and wrinkles in the EIFS. Another thing to observe is the condition of the caulk around the windows. If the condition is poor or non-existent, it is highly likely that there will be moisture damage to the EIFS. If the EIFS gives way and feels squishy, it may be loose or there may be a moisture build-up.

It is important to identify any issues with an EIFS, as it can save money and time in the construction process. If your construction site has EIFS that require inspection, contact Jeremy Lake at (716) 592-3980 ext. 133, or jlake@encorus.com.

Fun Fact Friday: Electrical Arc Flash Analysis

Fun Fact Friday: Electrical Arc Flash Analysis

One of the services provided by Encorus’s Engineering Design Group is electrical arc flash
analysis. Electrical arc flash analyses are a safety precaution used to prevent explosions
in industrial settings which utilize high electrical voltage. Director of Engineering
Design and Lead Electrical Engineer Tom Gilmartin offers more information on the subject.
According to Gilmartin, “When an energized wire touches another directly, this is known in
engineering as a fault, and commonly referred to as a ‘short’.  When this happens, the flow of
electrical current through the short has only the resistance of the wires from the generator to the
fault to limit its passage.  Generally, this resistance is very low, so the current flowing in the wire
rises very rapidly.  In a large home, the entire house has a maximum current of around 200
amps, although generally a house will never require this full current.  When a fault occurs in a
home, the current can rise as high as 20,000 amps, and in an industrial setting it is not
uncommon to see fault currents of 200,000 amps.  For a point of reference, lightning strikes are
typically around 1 million amps.  This high current can cause the phenomenon known as ‘arc
flash’.

Arc flash can occur when a very high current flows between two shorted wires.  As the current
rises, high amounts of energy are released at the point of the short, and the wires start to melt.
As the wires melt, the current will jump the gap, which is known as an ‘arcing current’,
commonly referred to as a spark.  The arc is actually made up of super-heated air known as
‘plasma’. The plasma can reach temperatures of 20,000 degrees.  As the arc forms and the
temperatures rise, the metal of the wires begins to vaporize.  If the arc is sustained long
enough, the vaporization of the metal can cause an explosion, which can approach the energy
levels released by blowing up a stick of dynamite!  Because of this, circuit breakers are used to
detect these high currents and open the circuit, which instantly cuts off the energy flow to the
arc before the energy can cause an explosion.

Fortunately, the relatively low voltage of home electricity cannot sustain an arc long enough to
cause such an explosion, so there is no danger of this in a normal home.  In industrial settings,
however, arc flash is definitely possible and engineers and electricians take precautions to
mitigate these risks.  Electric codes give us plenty of guidance for designing circuits to minimize
the chances of arc flash, and electricians are trained to identify circuits where the danger is
high.  In addition, engineers perform arc-flash studies on large electrical systems to find the
areas of high risk, and design in precautions such as special arc-flash detectors or separate
settings for use during maintenance.  With these methods and training, the risk from arc flash
has been greatly diminished in the last decades.  Engineers and electricians are always on the
lookout for new ways to make electrical systems safer for everyone involved, including workers
and homeowners.”

Arc flash analyses are vital to the safety of people and equipment in industrial settings
with high electrical voltages. If you require an electrical arc flash analysis, contact Director of
Engineering Design and Lead Electrical Engineer Tom Gilmartin, PE, PMP, LEED AP at (716)
592-3980 ext. 124 or tgilmartin@encorus.com.

Fun Fact Friday: Petrographic Testing

Fun Fact Friday: Petrographic Testing

When building any type of structure, it is important to make sure that the materials you are using are structurally sound to guarantee the integrity and longevity of the structure. Some of the most common materials that are used in modern construction are concrete products. Testing the integrity of concrete and other concrete products is referred to as petrographic testing. A full petrographic testing procedure is composed of two separate tests: the petrographic analysis and the air void analysis.

Petrographic analysis testing is performed on samples of hardened concrete or concrete products from construction sites, or existing concrete that has been exposed to natural elements. There are several reasons that a petrographic analysis may be necessary. They include the determination of:
• The condition of concrete in construction
• Causes of inferior quality, distress, or deterioration of concrete
• Probable future performance of the concrete
• Whether cement-aggregate reactions have taken place and their effects on concrete
• Whether the concrete has been subject to chemical attacks or the effects of freezing and thawing
• Potential safety concerns in the structure
• Whether concrete that has been subjected to fire is damaged
• Factors that caused a given concrete to serve satisfactorily in the environment in which it was exposed
• The presence and nature of surface treatments
• Investigation of the performance of the coarse or fine aggregate in the structure

Samples of the concrete product are taken by sawing off an appropriately sized piece (approximately one 6-inch diameter core) from the concrete at the field site. The procedure for a petrographic analysis includes a visual examination of the sample, followed by an additional examination using a stereomicroscope. If a conclusion cannot be drawn from the information gathered in the first tests, further testing may be done using petrographic or metallurgic microscopes, x-ray diffraction, or other chemical / physical tests.

A report on the findings is then prepared. If the concrete sample was being examined because of structural failure, this report details the interpretation of why the concrete failed based on the findings.

These procedures and reports are done by a concrete petrographer. Concrete petrographers need to be knowledgeable on concrete making materials, the processes of batching, mixing, handling, placing, and finishing of hydraulic cement concrete, composition and microstructure of cementitious paste, interaction of constituents of concrete, and the effects of exposure of concrete to a variety of conditions.

The second test that is used for the full petrographic testing procedure is the air-void analysis. This test is used to determine the air content, specific surface, void frequency, spacing factor, and paste-air ratio of the air-void system of the concrete sample. Examining these factors can help determine whether the concrete was damaged by the freeze / thaw cycle.

When concrete is exposed to the elements, water is likely to settle in the air-gaps. When the water freezes and expands, it could harm the structural integrity of the concrete. Therefore, it is important to calculate the size and frequency of the air-gaps to determine whether or not the concrete would be acceptable to use in construction.

The petrographic testing process is essential to the integrity of any concrete or concrete product structure. Without it, the concrete could be subject to structural failure that could have been prevented. If you need construction materials testing and inspection, including petrographic testing, contact Civil Laboratory Supervisor Jeremy Lake at (716) 592-3980 ext. 133 or jlake@encorus.com.

Fun Fact Friday: Architecture as a Discipline

Fun Fact Friday: Architecture as a Discipline

Encorus Group offers several interconnected disciplines that lead to the assembly of functional buildings and other structures. Our firm not only offers engineering disciplines, but can provide architectural services as well. For this week’s Fun Fact Friday, we will take a look at the architectural discipline at Encorus through the words of Senior Architect Dan Sullivan, AIA, CDT.

“As an architect at Encorus, I either support engineering services when their scope involves a building, an alteration to an existing building, space, or built component (roofs, walls, windows, etc.)  due to the addition or modification of mechanical, plumbing, electrical, or fire protection systems.  I also serve as the lead discipline in predominately architectural building type projects. In architectural / engineering building projects I am responsible for the building programing, planning, building mass, three dimensional, and exterior aesthetic quality of the building, working closely with the client to achieve their goals, and ensure that the project budget stays within the client’s budget for construction.

As the lead discipline, I work closely with engineers in the schematic, planning, design development, and construction documents phases to help in the selection process to coordinate and fit all the engineering systems in the building. Architects also monitor costs associated with those systems to ensure that they are within the construction budget.”

Architecture can be found on both the interior and exterior of every building / structure and is an important part of modern infrastructure. Encorus has provided professional architecture services to several clients in the commercial, healthcare, municipal, and institutional sectors, as well as other divisions. If you require architectural design services, please contact Senior Architect Dan Sullivan at (716) 592-3980 ext. 130 or dsullivan@encorus.com.