Frequently Questioned Answers about the use of ACM (Aluminum Composite Material) for architects and designers

Would there be any significant differences between high-end aluminum composite panels and cheap low-end alternatives?

Yes, there are and the differences are as follows:

  • Trustworthiness of the product, manufacturer and authorized distributors.
  • High quality products that are constantly improved and researched with good quality control by the world-class manufacturer
  • Warranty honorability and reliable after-sale services
  • Superior customer services and streamline ordering process
  • Good technical supports and product update
  • Tested and certified by universal rigorous standards and accredited regulatory bodies.

What are the types of coatings on the back panels? Do we need this back coating at all? Some distributors claim this is redundant since the material is aluminum?

The coating is high quality polyester coating or commonly known as “polyester powder coating”. This back coating is generally required as a standard protocol and it is applied to protect the back side of the aluminum composite panels from possible corrosion and oxidation. In the presence of high humidity outside the building or condensation formation from the cooler internal atmosphere in air conditioned buildings, corrosion can occur and shorten the panel life expectancy and produce undesirable paint blemishes and cracks. Corrosion of aluminum composite panels are natural but normally observed using microscopes. Without this back side coating, aluminum oxide formation occasionally causes the panels to disintegrate and crack as soon as within 15 months. The absence of back panel coating only produces relative small savings to the panel manufacturer, approximately 100-200 baht/m2 but potentially shortens the panel lifecycle significantly. For maximum protection, the standard thickness of back panel coating is recommended between 60-10 microns. An option of chromate coating is an obsolete process since it is very toxic and lethal to workers in the manufacturing plants.

What is the coating finish of ALPOLIC/fr? What are the advantages?
The coating finish of ALPOLIC/fr is high-performance and durable exterior paint coating backed by a 20-year warranty of the coating quality. Known generically as fluoroethylene vinyl ether (FEVE) or commercially as LUMIFLON, the paint coating resin has been constantly improving and upgrading the resin properties by Asahi Coat Tech Company (Japan). The newly developed FEVE resins have entirely overcome several weak points of the predecessor PVDF system as follows:
  • Superior weatherability with 20-year warranty of the coating quality
  • Exceptional gloss retention having the gloss indices (15-80%), which is not achievable in the PVDF coating system. Gloss characteristics does not only enhance the elegance and grander of the exterior design but minimize the dirt build up on the panel surface as well.
  • Brighter and more vivid panel colors
  • Unlimited possibility of color options enhancing grand visions of today’s architects and designers
  • Ability to repair the exterior finishes after installation as opposed to the PVDF system that requires factory curing at 250 oF for coating restoration.
  • Excellent resiliency of the coating film allowing great flexibility of panel folding and forming.
  • A wide spectrum of applications and references using this popular coating resin due to its outstanding physical and engineering properties surpassing the obsolete PVDF technology.

Limitations of the PVDF coating usage regarding its high temperature curing process

1) The application of PVDF coating technology, categorized as “thermoplastic fluorocarbon material” relies on high temperature curing process using the heat fusion method. As a result, this is a critical limitation of this technology that cannot allow the coating film to harden and cure at the ambient temperature or air drying (ambient curing) process.

On the other hand, the FEVE coating is initially processed and cured from manufacturing facilities via exothermic heat derived from chemical reactions (not from heat fusion). This coating technology gives rise to three distinct characteristics of the FEVE coating (i.e., pigment dispersability, coating adhesion and film flexibility). Also this FEVE coating enjoys good solubility, transparency, gloss, hardness and cross-linking property.

The ambient curing capability of this FEVE coating, categorized as “thermoset fluorocarbon material” allows the on-site coating repair and restoration at the room temperature. This property creates unparalleled flexibility for users to apply touch-up paint whenever and wherever.

2) FEVE technology is made of 100% fluorocarbon resins as opposed to only 70% resins in the PVDF coating

The PVDF alternatives, including Kynar 500 and Hylar 5000, were made of 70% fluorocarbon resins and 30% acrylic material. The melting point of this PVDF coating mixture takes place at rather high temperatures that helps disperse the fluorocarbon resin and acrylic material into thin coating films. This type of technology only generates low gloss indices between 25-40% due to the limited optical differences in the refractive indices of the two polymers. The FEVE coating technology, on the other hand, can create high gloss effect up to 80%.

3) Lighter polymer molecules in the FEVE technology VS heavier polymers in the PVDF coating

The polymer resins used in the FEVE coating have lighter molecular weights and excellent cross-linking ability owing to their alternating sequence patterns. These dense polymers arrange themselves very tightly having much higher density than the PDVF coating. For this reason, the FEVE coating has higher hardness, greater weathering resistance and more chemical resistance than the PVDF coating.

There are logical reasons indicating the superior weathering and chemical resistance properties of the FEVE coating:
1) Tested by 2 rigorous weathering evaluation methods below
2) Complied with the AAMA 2605 code. The FEVE coated panels have been exposed to extreme weathering conditions in South Florida for 10 years (the test detailed protocol can be found in the AAMA standard handbook or the technical bulletin from Mitsubishi Chemical America)
3) Comparison of chemical resistance properties among different coatings:

XENON-Weathering Test

EMMA(QUA) Weathering Test

UV : Mj/m2 (295-385 nm)

--------------------------------------------
Technical literatures (source: 3rd Party and world-class institutes capable of implementing both coating applications)
1) High Perfomance Fluoropolymer Coatings – provided by PPG Industies Ltd. (a world leader in paint coating)
Source: http://corporate.ppg.com/ppg/paf/documents/corwhite.doc

2) Thermoset Solution Fluorocarbon Coil Coatings – reported by Thomas E. Ballway (Executive VP of Keeler&Long Inc. , a subsidiary of PPG grop)
Source: http://www.p2pays.org/ref/03/02559.htm

3) Fluonova website, a leading paint applicator in Atlanta, Georgia, USA
Source: http://www.fluonova.com/index.html
Any query regarding to the technical properties of FEVE and PVDF coatings can be directed to the technical service of Fluonova at this email: tech@fluonova.com

What causes the black stains on ACM panels after installation? How to get rid of this undesirable stain?

Black streaks on the installed panels can be caused by dirt particles mixed with the diffused lubricant oil from the silicone sealant applied during installation. These stains can be easily and effectively prevented at the pre-installation step by using non-staining silicone sealants. These stains can be eliminated once and for all; however, this type of non-staining sealant costs more since it is produced from premium silicone material. Routine cleaning of building exterior must be done to dissolve dirt particle accumulation and prevent these black stains. Actually, there are alternative techniques other than the silicone joint method to install ACM panels on a building.

Comparison between wet joint silicone sealant and dry joint gasket techniques to install aluminum composite panels on building exterior

Wet joint silicone sealant method

Advantages

  • 1. There are a large number of references since it has been used for long time and applied to many buildings both domestically and internationally.
  • 2. No water leakage and easily applied to ACM panel installation
  • 3. Lower installation budget
  • 4. No need for the special aluminum frame structure
  • 5. Great flexibility and applicable to a broad spectrum of building designs and complexity
  • 6. When using with the steel mounting frames instead of aluminum frames, the wet joint technique allows easy on-site modification with high flexibility.


Disadvantages

  • 1. Prone to silicone stains and untidiness during construction since proper application of silicone is largely relied on the ejection equipment and system.
  • 2. Require highly-skilled, silicone-joint-experienced specialists
  • 3. Subject to installation delay due to raining or wetted construction conditions
  • 4. Long curing period as opposed to quick installation of the gasket joint technique
  • 5. Application of low quality silicone sealants produces untidy stains on the panels and short lifecycle of the material.
  • 6. Poor and unclean construction conditions during installation using silicone joint technique
  • 7. Silicone sealant has limited usage life and requires periodical routine inspection and maintenance.

Dry installation method (a gasket joint technique)

Advantages

  • 1. Enable cleaner construction conditions and minimize error since large number of panel preassembly can be done from factory. Do not require silicone ejection equipment.
  • 2. Easier installation system allowing installation by general skilled labors
  • 3. Installation is possible in a semi-wet condition (e.g., light rain, drizzling, etc.)
  • 4. Quicker installation comparing to the silicone sealant technique
  • 5. No dirt stains and messiness from silicone stains during and after installation
  • 6. Low maintenance and no post-construction blemishes due to frequent required inspection and maintenance


Disadvantages

  • 1. Only offered by a limited number of ACM panel contractors
  • 2. Possible water leakage since this technique requires the installation of a water drainage system, similar to Curtain Wall.
  • 3. Each contractor has its own design of panel mounting frame structures. Technical comparisons among different technologies or contractors are difficult.
  • 4. Only apply to simple structures and buildings
  • 5.
  • Less flexibility and difficult on-site modification since most mounting frame structure are made of aluminum. Installation attachment is restricted to only screws or adhesive tapes (no welding or on-site modification is possible).
What is the recommended cleaning procedure to remove dirt stains on the ACM panels?

1. Use the suggested cleaning solutions as described in the product pamphlets. These solutions are mild and gentle cleaning chemicals (e.g., diluted Magiclean mixture). For light stains, cleaning by water is always the useful cleaning method.

2. What is the best cleaning method and equipment for new and installed panels?
Always use soft sponge or cloth. For new panels, water suffices to clean and remove light dirt accumulation. For installed panels, the cleaning solutions recommended in the product pamphlet are safe and effective. Do not use isopropyl alcohol (IPA) if not necessary. Only use IPA as your last resource and use with cautions.

3. What degree that the ALPOLIC/fr panels can resist to strong acidic or alkaline solution?
The coating finish of the ALPOLIC/fr panels is formed using advanced fluorocarbon technology that provides unparalleled resistance to most harsh chemicals. However, the direct contact to strong acid or base for long period of time can alter the gloss index or produce a certain degree of discoloring. Immediately apply the panel surface with a lot of water to dilute the effect of the chemicals and clean the panel surface readily to avoid permanent coating damage.

4. What are the surfaces of ALPOLIC panels made of?
Generally, ALPOLIC/fr panels are made of 0.3 mm fire-retardant core (non-combustible mineral filled core) sandwiched by 0.5 mm high-quality aluminum skins front and back. The back coating is polyester paint to prevent corrosion and delay aluminum oxide formation. The front panel is coated using advanced FEVE technology with LUMIFLON-based fluorocarbon resins. This technology provides unsurpassed weathering resistance, exceptional gloss and low particle accumulation on the front panel surface. The coating quality is supported by a 20-year warranty against any color fading and discoloring of the panel paint. There is also an extra layer of special coating to prevent corrosion of aluminum sheet.

5. How often does the panel surface need to be cleaned?
According to the manufacturer’s product pamphlet, the proper cleaning interval is varied from 0.5-2 years between each cleaning. Nevertheless, the frequency of the cleaning also relies on the building surrounding and local climate.

What is the function of the plastic adhesive film coated on the panel surface?

The plastic film is designed to protect the panel surface from any potential scratches or damages during pre- and post-installation. Good protective film should adhere firmly to the panel surface and remain intact for at least 6 months. The graphics on the protective film may indicate the correct orientation of the panel for installation purpose and indicate the name and trademark of the panel manufacturer.

How to install the ACM panels? What is the appropriate design of the mounting frame structure and panel accessories? What is the cost estimation?

ACM panel is usually applied for building exterior. Water leakage, especially into the building interior, is one of the key concerns. Most contractors fabricate the panels into a tray-like shape and use 1 in. x 1 in. L-shape aluminum brackets to mount the panels to the frame structure. Screw and rivet mounting techniques are not common for the ACM panel installation. Generally steel mounting frame, made from 1 in. x 2 in. square pipes either anodized or applied by anti-rust paint, is very popular among new building projects. If the construction budget allows, the steel pipes can be replaced by aluminum pipes with an additional expense of approximately 400-600 baht/m2. However, the substitution of square pipes by L-beams is not recommended since the L-beam structures with screw joints cannot provide adequate support for the panels when the panel assembly is subject to strong draft wind or sudden lift force. The main benefits of the steel mounting frame lies on its flexibility and ease to be modified on-site. The aluminum structure, on the other hand, provides better durability against metal oxidation and corrosion. It is highly recommended to use only aluminum or stainless steel (with considerably higher price) screws to install ACM panels for better rust resistance.

How to select the right ACM panels for interior decoration to reduce project budgets?

The 4 mm ACM panels with the standard exterior coating is usually applicable to any interior decoration. When appropriate, the 3 mm thickness version of ALPOLIC/Fr LT panels can be used interchangeably at a more reasonable price. The modern architecture expands the ACM panel applications to a variety of applications, ranging from stylish covers for columns, beams and interior walls to grander decoration for entrance, ceiling and so on. Stone and wood pattern coating of ACM ALPOLIC/fr panels are very fashionable and on high demand for today’s building facades.

How many possible decoration ideas to use ACM panels for interior design?

There are infinite ideas to use ACM panels for interior visual improvement. ACM panels are applicable to many architectural designs as well as decorative finishes including walls, columns, beams, ceiling, etc. Inasmuch as the ACM panels are practical to a wide array of design applications, the panels are not suitable to use as floor surface or any other surfaces prone to attrition or friction by sharp materials. There are 4 standard ALPOLIC/fr panels with different sizes as follows:

1. 1270 mm x 2489 mm
2. 1270 mm x 3099 mm
3. 1575 mm x 2489 mm
4. 1575 mm x 3099 mm

However, customer’s order panels with a broad range of applicable widths and lengths can be fabricated by the manufacturer and are available through the authorized dealers. The APOLIC customer service can provide the criteria of appropriate panel dimension to minimize waste. For interior design, there is a wide array of decorative ideas to use ALPOLIC/fr panels including decoration of ceiling, interior wall, partition wall, etc. ALOPLIC/fr panels can be fabricated to suit many functions and uses (e.g., door panels, toilet partitions, pre-fabricated toilet accessories and décors, furniture and so on). All applications will enjoy the key fire rated characteristics as well as other benefits of the ALPOLIC®/fr aluminum composite panels as follows:

a. Fire retardant
b. Resistance to heat, moisture, high salt, acid, and dirt
c. Insect free and poor host for termites or living creatures
d. Mostly recyclable minimizing the use of virgin raw materials
e. No volatile organic compound (VOC) directly affecting the well-being of building users
f. Light-weight and strong composite material enabling versatile engineering flexibility of fabrication for designers. The rule of thumb is that any folding or manipulation possible on cardboards is possible to fabricate on the ALPOLIC/fr panels as well.
g. Large selections of colors and textures available, including natural granites, timbers, metals and recently new abstract patterns for interior design (e.g., leather, fiber carbon, etc).

  • More panel size selections and specifications with no additional cost
  • Low panel waste from cutting and trimming. Customized panels allow easy and fast installation.
  • World-class product quality. The ALPOLIC panels has been used worldwide and passed rigorous universal tests for fire resistance from accredited institutes.
  • Imported from Mitsubishi Plastics Inc. (Japan), the world’s number one ACM panel manufacturer with fire retarding cores having the largest production capacity over 10 million sqm/year with exceptional quality of manufacturing
  • Full 10-year coating warranty from the manufacturer.
  • High energy-saving materials minimizing global warming effect. Certified by major standardized organization for good environmental management and LEED (Leadership in Energy and Environmental Design) standard.
  • Cost effective investments both short and long terms

Figure 1 A wide spectrum of interior applications and installation

 

Figure 2 Fabrication of a curve shape décor and the bottom cover of the intricate stairway design using ALPOLIC/fr panels

 

Figure 3 Application of ALPOLIC/fr panels for interior wall, square and rounded column covers, stairway guard, and ceiling

 

Figure 4 More examples of ALPOLIC/fr designs for escalator, elevator, ceiling (with down light fixture), and building interior


The interior installation of ALPOLIC/fr panels has more options than the exterior installation, for example, the use of very high bond tapes.

 

Figure 5 Diagram of ALPOLIC/fr panel installation for interior use using VHB (Very High Bond Tape)

 

Figure 6 Diagram of ALPOLIC/fr panel installation using hook system

 

Figure 7 Diagram of ALPOLIC/fr panel installation using ceiling suspension

 

What are the differences between black and white core filling of ACM panels and how are these differences affecting the fire retarding properties? Realistically, the proof of fire resistance is only based on the fire test results.

For building designer’s considerations, only can the results of the fire tests from world-class institutions indicate the fire resistance or retarding property of the ACM panels. The texture, shape and color of the inner core materials provide no clue on the fire safety rating. Regardless of texture that occasionally is similar to white mineral powder, some commercially available panels may possess poor fire retarding property. There are a few criteria for qualified fire resistance materials derived from the fire test information.

Fire resistance tests of the ACM panels reflect the fire retardant property and proliferation of flame of aluminum composite materials. In the event of fire on high rise buildings constructed with ACM panels, most panels with Poly Ethylene (PE) inner cores fail on 2 critical factors that make those buildings unsafe.

1. PE is combustible and allows proliferation of flame at the temperature between 130-160oC. PE has a large value of heat of combustion even higher than gasoline. When fire takes place, it expands rapidly and extensively. High heat of combustion may facilitate the flame spread to other buildings. The melting PE is also a good fire fuel when these burning droplets of melting PE fly on to dry materials. This situation helps proliferate fire to other areas.

2. When PE catches fire, the burning smoke may compose of several toxic fumes, including aldehyde, cyanide, carbon monoxide, etc. These gases are harmful to fire victims trying to escape the building as well as firefighters and rescuers.

 

In many parts of the world, the building codes prohibit the use of aluminum composite panels with PE inner cores for both interior and exterior uses. In more advanced countries, like Singapore and Australia, their building codes demand stringent fire safety assessment of the ACM panels that must be tested and pass the “non-combustible material” and “non-toxic” tests. Unfortunately, the building codes in Thailand has not yet advanced or been able to specify the fire safety properties of commercial ACM panels.

When choosing ACM panels, how to spot the fire rated and non-toxic properties? Which tests are accredited by universal building codes and what about those institution’s credentials? There are several literatures addressing these concerns, which can be summarized into 2 main topics including poor fire rating tests to avoid and good standards to follow.

  • propriate ACM fire test protocols for fire resistance and fire spread indices



  • Cone Calorimeter Test - ISO 5660-1

    Photograph displaying the dripping of melted PE from a low-end ACM panel during cone carolimeter testing

    UBC 26-3 Interior Room Corner Test

      1. UBC 26–9 ISMA (Intermediate Scale Multi–story Apparatus) Test : (or NFPA 285)

      This test follows the American fire rated standards. The essence of the test involves the evaluation of burning flame spreading vertically along external cladding assembly. ACM panels passing this building fire simulation provide essential characteristics to ensure no fire spreading vertically to higher floors and laterally to other areas inside the building. The whole test lasts 30 minutes. For example, all external cladding installed in Singapore must fulfill this fire test standard (UBC 26-9 or NFPA 285).

       

    2. ISO 5660 – 1 Cone Carolimeter Test

    In Japan, this test is called the “Heat Release Test” (or universally known as “Cone Calorimeter Test”) and able to determine the combustibility or non-combustibility of the tested materials. The ACM panels with qualified fire retarding cores can pass this test readily; however, the panels with PE cores are self ignited, melted and dripped while releasing black smoke in the process. Generally, a cone calorimeter also includes the toxicity gas test.

    In Thailand, Fire Safety Research Center (FSRC) of Engineering Faculty, Chulalongkorn University provides the cone calorimeter test as described in the ISO 5660-1 standard. To have sample specimens tested, this research center is located in front of Rajamangala University of Technology Tawan-ok Uthenthawai Campus.

     

    3. UBC 26 – 3 or ISO – 9705 (Interior Room Corner Test)

    This test is applicable to the use of ACM panels as interior wall partition. The test is conducted by creating a fire in a corner of a mockup room and allows it to burn for 15 minutes. Fire spread and propagation, height of flame and temperature at 3/4 the height of room is analyzed on the test specimen that is used for interior partition or cladding.

     

    4. Combustion Toxicity Test

    Often fire incident does not totally destroy the whole building but it is lethal in the sense that the toxic fume or carbon monoxide produced from the burning fire suffocates victims or rescuers. The ACM panels passing the combustion toxicity test can give a peace of mind in that the degree of fire destruction can be lessened when such event happens.

Other aluminum composite panels with fire retardant cores do not have the same fire test certificates as mention eariler. Are there any other comparable tests?

Careful consideration must be taken on a case by case basis to determine suitable tests in evaluating ACM panels. Many fire tests are not applicable to aluminum composite panels with fire retardant cores but used only for advertisement purpose. These impractical tests can be misleading.

  • Cautions of ACM standards concerning fire rating and flame spread index

    – Arrangement of test specimen as described in ASTM E-84

    - BS 476 Part 6

    - BS 476 Part 7


      1. ASTM E 84 - Tunnel Test

      ASTM E-84 measures the Flame Spread Index of a test specimen in a chamber (length: 7.62m) as shown in Figure 1. The test specimen (0.5 x 7.32m) is positioned as a ‘ceiling’ in the chamber with a gas burner ignited below (see Figure 2). The gas burner is ignited for 10 minutes and the flame spread along the specimen is analyzed to classify the “Class” of the specimen.
      Class 1. With the Flame Spread Index (0 – 25), ACM classifies the material as low flame spread material.
      Class 2 .and Class 3. With the Flame Spread Index (26-75) and (76-200), the flame spread property is worsened as the number increases.

      Many aluminum composite materials with PE cores use this test to demonstrate that they are “incombustible”. However, due to the qualities of PE to melt and drip when exposed to heat, the flame spread along the material is misrepresented since the remaining is only the 2 aluminum skins. This test does not show the true behavior of fire spread of the PE core in ACM, but merely only measures the flame spread on the aluminum sheets.

      Actually, ASTM has specified in “ASTM E 84 – 06 Section 1.4 ” or “ASTM E84 – 00 Section 1.5 ” with the detailed description that “ Testing of materials that melt, drip or delaminate to such a degree that the continuity of the flame front is destroyed results in low flame spread indices that do not relate directly to indices obtained by testing materials that remain in place ” It is conclusive that this test SHOULD NOT be used for ACM. This is the fact that every few people recognizes.

       

    2. BS 476 Part 6, Part 7

    Both tests, like ASTM E-84, also tests the flame spread along the test specimen. Instead of placing the specimen in a horizontal position, it is vertically placed in open air with a heat source place emitting heat irradiance to it. In these tests, PE cores of the ACM panels drip and melt, leaving only the two (front and back) sheets of aluminum skin for analyzing the flame spread along the tested material. This test also misrepresents the true fire spreading properties of PE cores. The test only measures the heat radiated perpendicular to the test specimens; hence , the test temperatures are significantly lower than other tests, like UBC 26-9 ISMA Test, UBC 26-3 Interior Room Corner Test or ISO 5660-1 that uses gas burner applied directly on test panel with a heat shield to simulate high temperature condition.

     

    3. UL94 "Plastic Flammability Test" Class V0

    This test is popularly cited by many ACM manufacturers since the UL is a well-known standard reflecting high quality products. However, the UL tests like UL94 “Plastic Flammability Test” Class V0 is irrelevant to fire rating for ACM panels. The fact is this test is only applicable when testing the fire flammability of plastic materials. This test does not reflect fire resistance of ACM, but different degrees of plastic flammability. If an ACM manufacturer refers its products to this test, it only confirms that its panels have PE inner filling, not the fire retarding mineral cores that are used in the APOLIC/fr panels. The applicability of this test is for plastic skins of household appliances and the testing only limits to products with the gross area and thickness not exceeding 1 sq.m. and 13 mm., respectively. The UL 94 test also indicates in the UL website that it does not cover polymeric materials used for building construction, like ACM panels. Any UL 94 certification on ACM material is a false claim for a marketing ploy. More information of UL test can be found at http://www.ul-asia.com/news_nl/2007-Issue24/page10.htm.


All three aforementioned standards have loopholes to make false fire resistance claims. ASTM has acknowledged the situations and warned in its website for their appropriateness for PE core panels. As a result, the building codes in some countries, like Singapore and Australia, have declared clearly about the unsuitability of ACM panel with PE core as building materials for high rise buildings. This litigation stops the use of ACM panels with PE cores for build construction altogether.

This article aims to clarify misunderstandings about the use of ACM panels with PE cores and fire resistance criteria for construction materials. This is critical information affecting the safety and well-being of all stakeholders in using a high rise building. When the Thai building codes is being measured and more advanced, it is sincerely believed that the practical and appropriate standards of fire resistance construction materials are to be selected and taken into consideration as suggested in this article. Any misleading of fire resistance references can inflict serious or sometimes deadly consequences when a government or state puts lives of innocent people at risk.

Can ACM panels be used to construct fire protection partition as described in the Thai version of the building codes?่

By law, if the ACM panels are subject to the ASTM E119 test and pass the test at 1 and 2 hours benchmarks, the panels can be used as construction materials for fire partition. However, careful investigation of the ASTM E 119 standard revealed a few critical concerns as follows;

Appropriate use of ASTM E-119 standard

ASTM E-119 is most suitable for the fire rating assessment of coated or painted steel structures, for example, cementitious fireproofing or intumescent coating, to used for columns, beams and roofing structure. The testing simulates the realistic stress that these structures have to endure during fire incidents. A physical load is applied when the structures are subject to burning flame. However, this logical test for building structure is not universally appropriate as the only fire rating test for all type of materials, which have different functions of construction materials. For example, fire-proofed steel doors or aluminum composite panels may be inapplicable to this test and only relevant to other testing standards other than ASTM E-119.

The use of ASTM E-119 test for a system of wall panels or prefabricated walls can be systematically applied to validate the fire resistance properties of the whole wall assembly. There are a variety of modified systems that as a system they are certified for the ASTM E-119 standard. For example, as a system of fire-rated walls, the application of ACM panels attached to single layer or double layers of gypsum boards and filled with fire insulators, like rock wool or fiber glass, can meet the 2-hour requirement of ASTM E-119 standard. However, as an individual, that same ACM panel alone without the rest of the wall system cannot endure burning flame for 2 hours. The department of fire technology at Southwest Research Institute (SwRI) indicates clearly on the introduction of its certificate that the test result is only applied to the whole wall assembly as described in the certificate. Any modification other than the certificate description may not be adequate to fulfill the fire rated requirements of the test.

The ASTM E-119 standard requires that the average temperature on the opposite side of the burning panel does not exceed 139 oC plus the starting temperature (or the room temperature before the fire is started) or the maximum temperature must be less than 181 oC plus the starting temperature. In addition, immediately after the fire exposure, the burned panel has to be subject to the water hose stream test (there should be no destruction of the tested panel when water hose pressure is applied at 30 PSI for two and a half minutes).

Fire performance test conducted in the US showed that aluminum composite panel (ALPOLIC/fr) has passed all requirements of the ASTM E-119 standard with at least 2 hour of fire resistance when the panels was attached to 2 layers of 16 mm gypsum boards as shown the figures below. In this technical report of the fire performance test, it is stated that this panel does not impair fire resistant rating wall without the advertisement of 2 hour fire resistance as commonly used by other ACM panel manufacturers.



: Notes

- Most world-class laboratories, capable of performing standardized tests for commercial materials, always have rigorous testing protocols. To start with, their highly trained and authorized personnel randomly visits and take samples from different batches and they usually mark special emblems on the samples. Then the material owner can only select the test specimens from this sample group. This sampling procedure is to prevent using biased samples from different sources or predetermined batches of products. The evaluation of the samples performed internally by the manufacturer is generally an unacceptable practice.

- Most building codes do not accept the ASTM E-119 standard as a critical criterion for fire resistance of an individual wall material except for a system of wall assembly. For this reason, advanced countries perform or create more rigorous standards (e.g., UBC 26-9 or NFPA 285 in USA and Singapore, ISO 5660-1 in Japan, etc.).

What are the traits of good ACM panels with qualified fire retarding core?

There are world-class tests to assess essential fire resistance properties of qualified ACM panels.

  • ISMA (Intermediate Scale Multi-story Apparatus) Test (NFPA285)
  • Interior Room Corner Test (UBC 26-3 or NFPA 286)
  • ASTM E-108 (For Roof Covering) and ASTM E-108 Modified (For Wall Cladding)
  • Combustion Toxicity Test - New York Uniform Fire Prevention & Building Code
Complying with the energy-saving criteria aligning with the current building codes, what is the best way to apply or modify ACM panels to meet these stringent standards?

Any aluminum composite panels (e.g., ALPOLIC/fr panels) that are certified by ISO 14001, can be used to construct energy-saving buildings since their manufacturers have taken environmental management and energy and material saving in to consideration. Especially, ALPOLIC/fr panels with fire-retardant cores are categorized as a construction material that improves global-warming by LEED (Leadership in Energy and Environmental Design) from USGBC (United State Green Building Council) since 2007 for the following reasons:

  • Production lines are designed by the manufacturer who concerns social responsibility and is willing to comply with all regulations relating to the environment.
  • Meticulously select high quality raw materials and use cutting-edge coating innovation to ensure long-lasting color and gloss.
  • Use high recyclable content and minimize production waste
  • Low heat transmission effect
  • Comply with most world-class fire-safety standards and pass rigorous fire resistance tests
  • Production lines are designed to be extremely energy and material efficient and to comply with all regulations relating to the environmental management.
  • High safety standard and non toxic manufacturing for workers in the production lines as well as neighboring community
  • Meet universal and rigorous manufacturing standards from independent organizations, like ISO9001-2000 and ISO 14000

The detailed evaluation criteria of LEED can be described as follows:

  • Assessment of MR4.1 and MR 4.2 for recycled content (Post Industrial & Post Consumer Recycle Content)
    • Aluminum is a industrial metal that is one of the largest substances on earth’s surface, second to silicon.
    • Approximately 65%-75% of used aluminum can be reused.
    • Recycled aluminum uses less energy only 90-95 percent of the production of aluminum from bauxite ore.
    • The largest source of post consumer aluminum is derived from soda can scrap.
    • Recycling one aluminum soda can save electricity equivalent to turn on a 100W bulb for 4 hours as opposed to ore conversion.
    • ALPOLIC/fr surface skins use aluminum alloy 3105 H14 containing high levels of recycled content.
    • Detailed composition of recycled content in aluminum alloy 3105:
      While the exact percentage of recycled content can vary from coil to coil, the typical values of 3105 are as follows:
      • Composition of post consumer recycled aluminum is 48 percent.
      • Quantity of post industrial recycle aluminum is 48 percent.
    • Virgin aluminum is 4 percent.
    • Metal thickness with equivalent rigidity
      • 4 mm ALPOLIC panel = 3.3 mm solid aluminum sheet
      • ACM panels with the design of 2 aluminum skins sandwiched a mineral core have the same engineering strength as the H channel effect materials.
      • Manufacturing electricity usage
      • 3.3 mm solid aluminum sheet = 160 KWH/m2
      • 4 mm ALPOLIC panel = 60 KWH/m2
  • Assessment of MR 5.1 for regional content
  • ID 1.1 1.4 for innovative design
    • Reducing energy requirements
    • Solar heat Reflectance: ALPOLIC finishes with high solar reflectance helps reduce energy required to cool down inside the building.
    • Emissivity: Low-emissivity building materials minimize heat diffusion across the panel layer; hence, they save electricity of the air conditioning system.

 

Reduction of energy consumption

  • The use of ALPOLIC panels as building envelopes creates an air space between the structural wall and ALPOLIC panels. This air gap is a good thermal insulator and prevents heat diffusion into the building.

 

Reduction of energy requirement

  • The overall heat transfer coefficient (U value), W/m2*K
    (A lower U-value means less heat diffusion or higher heat insulation.)

    • RC wall only
      • U value = 2.5 W/m2*K
       
    • ALPOLIC cladding
      • U Value = 2.1 W/m2*K
       
    • ALPOLIC envelop with heat insulation
      • U Value = 0.92 W/m2*K

ALPOLIC/fr is aluminum composite panel with fire retarding core.

  • Tests of fire resistance according to universal standards for aluminum composite panels
    • Surface Flammability
    • Smoke Development
    • Multistory Testing-ISMA Test
    • Heat Release Test
  • Conventional tests vs Testing standards from world-class independent institutions
    • Conventional tests: less rigorous testing protocols and poor quality control often lead consumers to receive inferior quality products and the product and manufacturing qualities are varied and inconsistent.
  • Standardized tests from independent institutions
    • The test protocols are standardized and validated. There are authorized staffs from an independent third party to randomly sample products from the manufacturer for testing. Sampling is constantly taken every 3 or 6 months to ensure the quality consistency.

 

Here are some reasons why ALPOLIC panel is an environmentally friendly building material.

  • High Responsible Manufacturing Practices
  • High quality material and durable Finishes
    • The long-lasting color and gloss help reduce long-term maintenance costs and frequent renovation.
  • Cutting-edge and innovative Finishes
    • Provide a variety of panel surface and coating to suit any construction design and at the same time help reduce energy consumption.
  • High recycled content
    • Reduce pollution from toxic aluminum smelting process.
    • Highly energy efficient manufacturing process
  • Low heat transmission effect
    • Good insulation material with minimal energy transfer across panel saving energy consumption.
  • Good fire resistance property and high fire safety standard
    • Pass world-class fire resistance standards from independent institutions, like UBC 26-9 or NFPA 285, ASTM E108, UBC 26-3, etc.
    • Minimize fire destruction and building damage

 

How do ALPOLIC/fr panels perform as a sound shield material?

Most 4 mm ACM panels with fire retarding cores has the sound shield index or STC of approximately 26. Conventional 100 mm concrete walls with inner red bricks layer has the STC of 45. The thickness of the ACM panels is 25-fold less but shares relatively the same STC value as concrete walls. This good acoustic shield trait has been exploited for building design by many architects and designers.

How are ALPOLIC/fr panels made? Does poor ACM panel manufacturing process result in the delamintion of the panel surface?

The fabrication technology of the ACM panels does substantially affect the quality of the final products. Most of the poor quality panels is easily subject to panel damages after installation. Architects, designers and contractors should ask for the warranty certificate of the product against any post-installation quality inferiors, especially delamination of the panel surface. Qualified ACM panel manufacturer may provide such warranty for at least 10 years.

Unlike other aluminum composite brands, ALPOLIC®/fr uses only 0.5 mm thick aluminum sheet grade 3105-H14 on both topside and backside skins with a non-combustible mineral-filled core. The continuous in-line process using thermo bonding bonds the two aluminum sheets with the fire-rated core while the core is still in liquid state. This enables a very solid bonding between the aluminum sheets and the core without using adhesives and preventing future delamination.

For skyscraper icons, like Baiyoke Tower, can ACM ALPOLIC/fr panels provide adequate wind resistance against any deflection if there is a need for any future renovation or new construction?่

The application of ACM panels on high-rise buildings can experience strong wind pressure causing panel deformation or deflection. Not only deformation degrades the exterior beauty of the building but strong wind force can damage ACM panels and cause the panels to detach from the building. Hence, the use of ACM panels for skyscrapers must evaluate the panel and structure strength and include necessary safety factors. Reinforcement may be necessary to prevent future damage of the panels by taking into account several design factors as follows;

1. Wind load or the height of panel installation to stringently comply with the building codes
2. Panel size to be installed at a certain building height
3. Orientation of panel installation (vertically or horizontally)
4. Allowable deflection
5. Mounting frame reinforcement (steel or aluminum frames)

These design factors are used to estimate optimum design of panel assembly using a designated design program. The final design is to be presented to the project consultant team of building façade.



Example of wind load calculation
How to obtain the preliminary usage and cost estimate of ACM ALPOLIC/fr panels? Is there any way to reduce panel waste?

There are rules of thumb for architects and designers to estimate the cost and useage of ACM ALPOLIC/fr panels. The panel cost can be divided into 2 main expenses;

  • Cost of ACM panels (for 4 mm panel thickness) averaged at 1,450 baht/sqm
  • Installation cost (including labor, mounting steel structure and silicon sealant) estimated at 1,200 baht/sqm
  • Installation waste due to panel trimming (approximately 10-20%) averaged at 145-290 baht/sqm
  • When all three expenses are combined, the total cost of using ALPOLIC/fr panels is between 2,850 and 3,000 baht/sqm without the overhead of contractors.

The cost can be further reduced by considering strategies to minimize panel waste. Only few manufacturers that customers have flexibility to select from a wide range of panel sizes and can control the panel waste at the factory by choosing the appropriate panel dimension with minimal waste.

There are 4 standard ALPOLIC/fr panels;

1. 1270 x 2489 mm
2. 1270 x 3099 mm
3. 1575 x 2489 mm
4. 1575 x 3099 mm

These are standard sizes similar to most ACM panel manufacturers. These standard sizes are the most popular and mass produced to lower the production cost. But ALPOLIC/fr manufacturer provides options for customer to order special panel dimension. A special order can be placed to minimize panel waste during installation. The ordering process is straightforward and has simple criteria as follows;

1. The customized width of the ALPOLIC/fr panel is ranging from 916 mm to 1620 mm.
2. The panel length starts at 1800 mm and can be as long as 7200 mm. There is no additional charge for customized panels but unfortunately there is a minimum order quantity.

The unit format is in millimeter and the desirable width or length can be specified down to the very last digits. For example, the width can be selected from any applicable numbers (say, 999 mm. or 1212 mm). A similar idea applies to the length specification, no need to round the numbers up to every 10 or 20 mm. For the sake of order process demonstration, ALPOLIC panel usage for a medium-size building is estimated at 3,500 sqm and used as an example. The designer specified the panel dimension of 1040 mm x 2040 mm. Having the end folding of 40 mm, this building requires 1,750 pieces of ALPOIC/fr panels.

“With the ACM ALPOLIC/fr manufacturer, this panel specification (1040 x 2040mm) is fulfill and leaves no panel waste (or 100% panel sheet usage).”


Most low-end ACM manufacturers claim low-cost advantage but consumers must accept some quality downgrading with quite a few product restrictions, among other things, dubious fire-rating information and questionable product warranty, inferior manufacturing and poor coating finish qualities, etc. Worse, there are limited selections when it comes to panel sizes and customized order options. Users have to figure out common sizes from the standard panels and trim them off producing a lot of useless waste. For example, the popular standard panel size from low-end ACM manufacturers is 1250 x 2440 mm. From the above user’s requirement of 1040 x 2040 mm panels, there are some trimming of 210 mm width and 400 mm length. The panel trimming creates 0.39 sq.m. panel waste or up to 30.49% of unused area. This is a sizable lost, isn’t it. What if a bigger building has to use these low-end ACM panels, the panel waste can increase tremendously depending on the complexity of the building shape and design. Putting all these losses into the equation, the waste of construction may be accumulated to 300 baht/sq.m. and increase the total cost of the cheap panels to 1,300 baht/sq.m. (after all not much cheaper than the world-class, high quality ALPOLIC/fr panels).

 

The benefits of using ACM ALPOLIC/fr panels with fire retarding mineral-filled core can be summarized as follows:

1. More size selections and a variety of products with no additional charge
2. Low panel waste from cutting and trimming. Customized panels allow easy and fast installation
3. World-class product quality. The ALPOLIC panels has been used worldwide and passed rigorous universal tests for fire resistance from accredited institutes.
4. Imported from Mitsubishi Plastics Inc. (Japan), the world’s number one ACM panel manufacturer having the largest production capacity over 10 million sq.m./year with exceptional quality of manufacturing
5. Full 10-year coating warranty from the manufacturer.
6. High energy-saving materials minimizing global warming effect. Certified by major standardized organization for good environmental management and LEED (Leadership in Energy and Environmental Design) standard.
7. Cost effective investments both short and long terms

Vice versa, the users who select the low-end cheap products may face several foreseeable problems as follows:

1. Limited size selections and products. No backup stock so customers are required to order in high quantity at one time. There is a lot of panel waste such that at the end of the day customers may end up spend more (up to 30% due to panel waste).
2. Excessive panel waste from cutting and trimming. So many sizes causing confusion in differentiating waste and usable panels. This situation will slow down installation process and require more labors to sort things out. More installation cost.
3. Dubious standard certification and limited technical supports on product qualities for both coating quality and fire safety rating.
4. Manufactured from unreliable small OEM factories with questionable warranty creditability
5. Low gloss, discoloring, and faded color coating finishes. Some manufacturers reduce the coating quality by using interior for exterior coating.
6. Wasteful manufacturing energy and poor material usage in the production lines. Not environmental friendly.
7. Poor short and long term investments since customers end up spend relatively the same for low quality products or in some case the higher overall expense when all things are considered.

Is it true that the installation of ACM ALPOLIC/fr panels can be done in any orientation regardless of the recommended direction indicated by the arrow signs on the panel?
It is highly recommended to obey the installation orientation as suggested by the arrow emblems on the panel surface. Even though the ALPOIC/fr panels are highly uniform in color and manufactured using cutting-edge coating technology, it is advisable to follow the coating finish orientation as the manufacturer’s recommendation for smoother color uniformity and overall ecstatic look of the building. When there are distinct discrepancy of color shading, one should contact the manufacturer or authorized dealers for panel replacement.

How to the use of non-staining silicone sealant on ACM panels? Any suggestion to effectively apply this type of sealant on ACM panels?

It is a good investment to select a non/less staining silicone sealant over an ordinary weather sealant. Although the conventional silicone sealant is cheaper, the non/less staining version is worth the extra money since it can substantially reduce the dirt and silicone stains on and around the panel joints during installation. Also the quality and life expectancy of this silicone generally are better than the conventional weather sealant.

When the budget is tight, the conventional weather sealant may be adequate. However, there are also noticeable differences of silicone qualities among the conventional silicone sealants. The popular and high quality brands often have better quality control and, hence, much better silicone quality. The use of polyurethane (PU) sealant is not recommended. Not only the PU sealant is UV sensitive and requires additional UV paint coating, the chemicals in the UV material can damage the fluorocarbon paint coating. Although PU sealant prevents oil stain formation during installation, this material has short life span, especially upon the exposure to UV ray. Under strong UV exposure, the PU sealant is quickly hardened and potentially damaged; as a result, the sealed gaps between panels are subject to water leakage.

What is the latest technological update on the ACM panel coating? What are the advantages of these cutting-edge coating?

Recent advances of the ACM panel coating technology include the prismatic color coating that enables the display of two color shades in the same panel coating. This coating technology is discovered during an attempt to simulate the natural color saturation of solar reflection. The dynamic dual color display of this coating beautifies the building exterior in a subtle way that is very attractive and streamlined with the local landscape.

The sparkling effect of the prismatic color coating makes the building and its surrounding (e.g., trees, lawns, etc.) shined and radiated naturally. Especially after raining, the sparkled building exterior may puzzle and astonish passerby and leave the impression that perplexes many people to wonder whether the rain droplets or the panel surface giving those spectacles. Actually, this astounding look relies on the physics of lighting where those rain droplets act as Prism glasses. When these tiny prisms reflect sun light, the building exterior radiates dazzling beauty. The human’s visual perception differentiates the spectrum of rainbow into 7 colors (usually notice only 4 distinct colors)





: When sun light pass through the prism glass, a spectrum of 7 distinct colors at different wavelength intervals can be observed. The rain droplets or morning fog can display the visual gradient of natural beauty and convert dull white light to 7 spectrums of colors “or rainbow”.


There is a way to bring in dynamic colors from the natural beauty and apply it to decorate modern buildings. This is a new panel coating technology that is currently in trend. The concept is the creation of dazzling sparkles by combining tiny drops of water with the hidden magic of sun light to alter the beauty of building exterior forever.

: Photo of the ACM Materiales de Aluminio Compuesto Building in Costa Rica. Using prismatic color coated panels
The new development of ALPOLIC coating technology makes use of water droplets to facilitate color dynamic display of building exterior. Relying on the physics of prisms and holographic pigments, the visual perception of a build is further enhanced and dynamically altered. The ever-changing colors of ALPOLIC panels depend on the lighting conditions and the location. The prismatic color coating technology encompasses 12 shades of colors to combine with the exceptional features of ALPOLIC/fr panels with fire retarding cores. There is still the same full 10 years warranty on these new coating of APOLIC/fr panels from the manufacturer.

Are there any foreseeable problems during installation to utilize low-end ACM panels? Any examples?


There certainly are several concerns of using poor quality ACM panels and plenty of photos to elucidate the problems.

Warping or undulation deformation of ACM panels

Color fading and dirt staining

Warping and undulating as a result of poor installation. Discoloring and dirt stain

accumulation.

Panel deformation

Panel deformation

Discoloring and staining

Panel deformation and warping

 

Edited by
  • Sasin Vibulbandhitkij
    Product Manager B.F.M. Co., Ltd.
  • Suttipun Wanwinwet
    Sales Consultant B.F.M. Co., Ltd.
    suttipun@bfm.co.th

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