Figure 1 Brick & Block Cavity Wall

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1 Introduction The Wall System is a method to install rigid, STYROFOAM Brand CAVITYMATE Ultra extruded polystyrene insulation boards in a manner which achieves air/vapor barrier properties in addition to continuous thermal insulation. These air/vapor barrier properties are achieved by sealing the STYROFOAM board joints with GREAT STUFF PRO ** single component insulating foam sealant. The result is an inexpensive yet effective system which provides essential continuous insulation and air/vapor barrier properties to brick and block cavity wall systems. Foundation DETAIL - Face Brick Wall Tie STYROFOAM Brand CAVITYMATE Ultra Concrete Block Air Space GREAT STUFF PRO Gaps & Cracks Termination Bar Base Flashing History of Brick and Block Cavity Wall Systems Brick and block cavity walls are one of the oldest wall systems. The separation between the brick and the block forms a rain screen cavity which acts to drain the wall, making for a much more water resistant system. Flashing at the bottom of the wall cavity directs the draining water through weep holes to the exterior (Figure 1). Figure 1 Brick & Block Cavity Wall The rising cost of energy in the 1960s and 1970s led to the placement of thermal insulation in brick and block cavity wall assemblies to maintain the ruggedness of both the veneer and the interior surface (Figure 2). Figure 2 Brick & Block Cavity Wall with Insulation However, both brick and block are highly porous to air. Moving air flows around the insulation causing a loss of conditioned air and consequently a loss of energy. Designers began placing air infiltration barriers in the brick and block cavity wall assembly, typically against the exterior of the block. The first of these were trowel applied but both sheet and liquid applied layers were later introduced. Applying an air barrier product to the block wall is an expensive additional step in the cavity wall construction process. What was needed was a way to install both the insulation boards and the air barrier at the same time in the same layer. Attempts have been made to do this with caulk/ sealant products, but caulks are slow, hard to use, and expensive. A system approach was needed that was fast, effective and inexpensive. Through this effort, the was born. The Wall System uses GREAT STUFF PRO Gaps & Cracks single component insulating foam as both a sealant and an adhesive with STYROFOAM Brand CAVITYMATE Ultra Insulation, to construct a single thermal and air barrier layer. This is achieved by applying a bead of GREAT STUFF PRO Insulating Foam Sealant between horizontal & *R means resistance to heat flow. The higher the R-value or RSI (R-Value Système International), the greater the insulating power. **Read the label and Material Safety Data Sheet carefully before use. 1 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 1

2 vertical joints after the boards have been installed. Securement of the insulation to the block wall is accomplished with the proper placement of GREAT STUFF PRO on the block wall (See Figures 3 and 4). The result is a continuous layer of high R-Value thermal insulation completely sealed from air infiltration. Figure 3 Figure 4 Desired Cavity Wall Insulation Properties Why choose STYROFOAM as the insulation for this system? The cavity in a brick and block cavity wall system can be a harsh environment. Also, cavity space is at a premium, so any insulation installed in the cavity has to pack a lot of R-Value into each inch to get the most out of that precious space. So, high R-Value per inch is an important property for an insulation within the cavity wall. STYROFOAM Brand CAVITYMATE Ultra Insulation has an R-Value of 5.6 per inch, the highest of any polystyrene foam plastic insulation. It provides 16.8 Rs of insulating power into 3 inches of space. In addition, the high R-Value is not dependent on additional facer technology which can be comprised during installation, like some other insulations. It is an inherent property of the foam plastic itself. This R-Value is backed by a 50 year thermal warranty. But high R-Value by itself is not enough. As mentioned above, rain water penetrates the brick veneer and saturates the cavity as it makes its way towards the weep holes. Any insulation in the cavity will be exposed to that water for long periods of time. And water is the bane of every insulation. Water absorption significantly reduces the R-Value of an insulation so any insulation installed in a brick and block cavity wall must be highly water resistant. STYROFOAM Brand CAVITYMATE Ultra Insulation is the most water resistant type of insulation available, able to resist moisture in all its forms over long periods of time. Laboratory testing of various types of foam plastic insulation in extended water exposures has revealed that Extruded Polystyrene (XPS) foam plastics are the most resistant to water absorption, resulting in greater retention of R-Value in harsh conditions like a brick and block cavity wall (See Figure 6). Figure 5 STYROFOAM Brand CAVITYMATE Ultra Extruded Polystyrene Foam Insulation Figure Modified ASTM D2842 Molded Bead Polystyrene Water absorption % by volume Polyisocyanurate (Foil-Faced) STYROFOAM Brand Extruded Polystyrene Foam Insulation Time, days 20 2 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 2

3 The combination of high R-value and water resistance make STYROFOAM Brand CAVITYMATE Ultra Insulation an excellent choice for use in the narrow, wet environment of brick and block cavity walls. Desired Cavity Wall System Properties Choosing the right insulation for a brick and block cavity wall is not enough, it has to be installed as part of an insulation system if it is going to have all the necessary physical properties to fully insulate and seal the wall assembly. In addition to R-Value, a wall assembly needs to resist air infiltration. Air moving through a wall system is a significant form of energy loss in commercial buildings. This is why many buildings are tested for their air infiltration properties to determine whether they are adequately performing and truly energy efficient. STYROFOAM Brand CAVITYMATE Ultra by itself has the air barrier properties to completely block any air infiltration. It has passed the ASTM E2178 air barrier test for materials. But what about the gaps between the installed boards? Those gaps will have to be sealed to achieve the air barrier properties for the wall systems that are specified in some building codes and desired by many designers. The test procedure ASTM E2357 Standard Test Method for Determining Air Leakage of Air Barrier Assemblies measures wall assemblies for their ability to resist air infiltration. This procedure not only tests the opaque part of the wall assembly, but also the ability to seal around penetrations in the test wall. Any wall system successfully passing this test will have demonstrated the capability to be a very effective air barrier. Figure 7 ASTM E2357 Test Apparatus Figure 8 GREAT STUFF PRO being installed between board joints ASTM E2357 requires air leakage testing in both the exfiltration (negative pressure) and infiltration (positive pressure) modes. Upon being properly mounted and sealed into the test apparatus, the specimens were subjected to positive and negative pressures of 25, 50, 75, 100, 150, 250, and 300 Pa (this corresponds to 0.52 to 6.3 psf). When the board joints of STYROFOAM Brand CAVITYMATE Ultra are sealed with GREAT STUFF PRO ** single component insulating foam sealant in a cavity wall assembly, the resulting layer of insulation and sealant becomes an effective air barrier. The air barrier qualities of this system have been tested using the ASTM E2357 method and have demonstrated the lowest possible air infiltration rate which easily passes all current code and certification standards in North America. The Air Barrier Association of America (ABAA) in an effort to support the design community has defined a process to evaluate key product and assembly requirements to meet the definition of an air barrier. This evaluation is a comprehensive review of the product/assembly s capability to effectively perform as an air barrier. External (third party) testing is required for this review, including ASTM E2178 and ASTM E2357 described above. Additionally, other key physical property performance metrics are evaluated such as water vapor transmission, compressive strength, and water absorption. The has been evaluated against all of these performance metrics and has been approved by ABAA as an air barrier material and assembly. **Read the label and Material Safety Data Sheet carefully before use. 3 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 3

4 CODE REQUIREMENTS FOR FOAM PLASTIC INSULATION Foam plastic insulation products have some of the most stringent requirements governing their use, especially in commercial construction. The 2012 IBC Chapter 26 (Plastic) regulates use of plastic materials used in construction. The Wall System meets the prescriptive compliance path laid out in the 2012 IBC, Chapter 26, Section : Exterior Walls of Buildings of Any Height. Seven Elements of IBC Chapter 26 There are seven elements to this section of the code that define foam plastic insulation products and their specific use in a commercial wall of Type I, II, III or IV construction Fire-Resistance Rated Walls - Commercial walls may need to meet fire-resistance requirements (ASTM E119, hourly rating) based on the type of construction, occupancy of the structure, or separation distance from other structures. The Ultra Air Barrier, with brick veneer, has achieved a 1-hour rating as a non-load bearing wall assembly per assembly U902. This assembly may be accessed via the UL directory: cgi-bin/xyv/ cgifind.new/ LISEXT/1FRAME/ index.html Thermal Barrier - Any foam plastic must be separated from the interior of a building by an approved thermal barrier per Section The block of the brick and block system in the serves as the thermal barrier Potential Heat - The potential heat energy of foam plastic insulation in any portion of the wall cannot exceed the potential heat energy of the foam plastic insulation contained in the wall assembly tested in accordance with Section The National Fire Protection Association s NFPA 285 testing has been conducted on three separate systems incorporating STYROFOAM Brand Insulation and have been described in the engineering study by Hughes Associates (HAI Project No.: 1JJB ). This engineering study covers assemblies with up to 3 inches of any Type IV STYROFOAM XPS insulation including STYROFOAM Insulation. The potential heat energy of STYROFOAM Insulation per NFPA 259 testing is approximately 18,000 Btu/lb Flame Spread and Smoke Developed Indices - Foam plastic insulations must have a flame spread index of 25 or less and a smoke developed index of 450 or less as determined in accordance with ASTM E84. STYROFOAM Insulation complies with this requirement up to a maximum thickness of Test Standard NFPA The wall assembly must be tested in accordance with NFPA 285. The test is referred to in the industry as the Multistory Flammability Test. The Ultra Air Barrier is approved with standard brick veneer per NFPA 285 testing (see above) Label Required - This section requires proper labeling of the foam plastic by an approved agency. The bundle unit label of STYROFOAM Insulation shows the Underwriters Laboratories (UL) logo as its approved agency Ignition - A wall assembly must not ignite from the exterior side of the wall when tested in accordance with NFPA 268. A brick veneer is a thermal barrier and thus meets the exception list for this requirement. 4 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 4

5 Table 1: Commercial Energy Code Prescriptive Requirements Climate Zone /2010 R-Value STYROFOAM CAVITYMATE Ultra Thickness Needed IECC 2009 R-Value STYROFOAM CAVITYMATE Ultra Thickness Needed IECC 2012 R-Value 1 NR 0" NR 0" 5.7 ci 0" ci 1.75" 5.7 ci 1.75" 5.7 ci 1.75" ci 1.75" 7.6 ci 1.75" 7.6 ci 1.75" ci 1.75" 9.5 ci 1.75" 9.5 ci 1.75" STYROFOAM CAVITYMATE Ultra Thickness Needed ci 2.125" 11.4 ci 2.125" 11.4 ci 2.125" ci 2.5" 13.3 ci 2.5" 13.3 ci 2.5" ci 3.0" 15.2 ci 3.0" 15.2 ci 3.0" ci 3.0" 15.2 ci 3.0" 25.0 ci 4.75"* * More than one layer will be necessary. Table 2: Sizes, R-values and edge treatments for STYROFOAM Brand cavitymate Ultra Extruded Polystyrene Foam Insulation Nominal Board Thickness (1), In R-Value (2) Board Size, In Edge Treatment /4" x 96" Square Edge /4" x 96" Square Edge /4" x 96" Square Edge /4" x 96" Square Edge (1) Not all product sizes are available in all regions. (2) R means resistance to heat flow. The higher the R-value, the greater the insulating power. R-values are expressed in ft 2 h F/Btu. R-value determined by ASTM C518. Basic Installation The installation of the Ultra Air Barrier is a simple process. Not only is it simple, it is easier for the mason to install because it goes up in one smooth process. And the system can be installed under a wide set of environmental conditions which simplifies scheduling. STYROFOAM Brand CAVITYMATE Ultra Insulation also comes in a new board width allowing easier fitting in between wall ties. The new width of 15 ¾ inches speeds up the process of fitting boards between wall ties (See Figure 9). STYROFOAM insulation also comes in greater thicknesses, up to three inches (See Figure 10), for higher system R-Values (See Table 2). Meeting Energy Codes and LEED Fire and safety are not the only aspects of the Building Code that have to be met by a wall system. It must also meet the requirements set forth in the commercial energy codes: the International Energy Conservation Code (IECC) and ASHRAE 90.1 Energy Standard for Buildings Except Low-Rise Residential Buildings. These codes prescribe the insulation requirements for all wall assemblies. The requirements are broken up into eight climate zones (See Table 1). The Energy Codes are not the only initiative driving higher insulation levels in building envelopes. The Leadership in Energy and Environmental Design (LEED) initiative from the US Green Building Council (USGBC) not only requires that a building exceed the energy code by 10% to qualify for certification, it offers certification points for further surpassing the energy code. The version of the Energy Code used by LEED 3.0 is the ASHRAE edition. The Energy and Atmosphere (EA) portion of the LEED 3.0 rating system outlines the percentage improvement in the proposed building performance that must be met for each point threshold. Using greater amounts of STYROFOAM Brand CAVITYMATE Ultra insulation in the cavity can help in achieving these points. Figure 9 New board width (15 ¾) to quicken installation. Figure 10 Greater thickness (3 ) to reach higher R-Values. 5 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 5

6 GREAT STUFF PRO Gaps & Cracks Insulating Foam Sealant** is ideal for gaps, joints and penetrations up to 3 by expanding to form an airtight and water-resistant seal that repels and deflects water. It bonds effectively to STYROFOAM Insulation, masonry, metal, glass, wood and most plastics. It cures quickly (tack-free in minutes, trim within 30 minutes). 1 PRO Series Foam Dispensing Guns maximize yield and install consistency and allow up to 30- day restartability. Application Steps The first course of insulation requires additional extra adhesion support to the wall. Apply a one inch bead of GREAT STUFF PRO Gaps & Cracks Insulating Foam Sealant on the wall above the flashing and just below the first row of wall ties (if a termination bar is not used, apply the sealant just above the flashing to create the air seal). Angle board and insert the bottom of the board into the corner of the base flashing and then rotate the top onto the wall between the brick ties, bending the ties up or down to ensure a snug fit. Make sure board is pressed firmly into the GREAT STUFF PRO Insulating Foam Sealant Adhesive. Install adjacent boards across the rest of the bottom course the same way. Best Practices for using PRO Series Foam Dispensing Gun Using the gun 1. Shake the can well. 2. Screw the can on the adapter, holding the gun upside down. 3. Open the set-screw by turning it counter clockwise: the trigger is deblocked. 4. The PRO gun is now ready to be used. 5. The foam output can be closed by activating the trigger/by turning the set-screw. 6. As soon as the can is empty, replace it with a new one. 7. If the gun is not used within 30 days, leave a can containing foam on the screw adapter; make sure that the can is stored in a vertical position. 8. If the can is empty, remove it and clean the gun in order to prevent foam from curing inside the gun. Cleaning the gun 1. Unscrew the can holding the gun upside down. 2. Remove remaining foam from the nozzle and the basket with cleaning fluid (never use water). 3. Screw a cleaner can on the adapter, holding the gun upside down. 4. Activate the trigger in order to fill the gun with cleaner and spray until all foam has come out of the barrel. 5. Leave the cleaning fluid in the gun for several minutes. 6. Spray again by activating the trigger. 7. Remove the cleaner can. 8. Activate the trigger until the gun is completely empty. 9. The gun is now clean and can be used again or left aside for a longer period. Troubleshooting: 1. In case foam leaks out of the gun even when the trigger is not activated, take a cardboard box and give a short output by pulling the trigger as far as possible and release at once. The needle will return back to its original position. Alternatively, a complete check-up can be performed: a. Unscrew the can and follow instructions under Cleaning the Gun. b. Remove the needle and clean up tip with solvent. c. Remove the nozzle and check whether it is worn out or polluted. In the event it is no longer in good condition, replace with a new one. *Read the label and Material Safety Data Sheet carefully before use. 1 Actual cure time will depend on temperature, relative humidity and size of foam bead. INSTALLING REMAINING COURSES Cut first board of second course to 4 in length, this will allow for staggering of vertical joints Apply (5) balls of GREAT STUFF PRO to wall in pattern shown here (2 deep by 3 wide) Angle board and rotate onto the wall between the brick ties as previously shown Press board firmly against the wall to ensure contact with GREAT STUFF PRO Gaps & Cracks Insulating Foam Sealant. Insert nozzle of GREAT STUFF PRO Gun in between all vertical & horizontal joints and fill with GREAT STUFF PRO Gaps & Cracks until bead of foam is visible at the surface edge. Installing Around Penetrations Cut foam ~1/2 to 1 larger than the measured penetrations. Slide board over penetration Use GREAT STUFF PRO Gaps & Cracks Insulating Foam Sealant to fill in the void between the penetration and the board See the installation manual for the Ultra ( for more in depth installation instruction and tips for windows, parapets and more. 6 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 6

7 Dewpoint/ Condensation Issues? Wall moisture condensation issues are an important consideration in any wall system. There are a variety of methods that can be used to investigate condensation issues. One of the most common methods is the standard Dewpoint analysis. This simplified mathematical model* compares the actual temperature through the wall (based on component R-Values) and the Dewpoint temperature through the wall (based on component perm ratings). Older style brick and block cavity walls with a separate vapor/air barrier perform very well when modeled with this kind of analysis and that performance is proven out in the real world. A suitable vapor barrier on the block wall allows this wall design to perform well in winter conditions. However, proper selection of the vapor retarder properties can be important in different geographies depending on warm dominant or cold dominant climates. Placement that works well in one climate does not necessarily work well in another. To the right you can see two analyses that were done on an assembly with the air/vapor barrier placed on the block. This works well in a winter climate but has the potential for condensation problems in the summer. * Model based on the method outlined in the ASHRAE Handbook of Fundamentals. 7 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 7

8 Dewpoint calculations performed on the reveal a system remarkably resistant to potential condensation issues regardless of the direction of vapor drive. The calculations on the left show low to no condensation potential in both cold and warm climates. Key Learnings The Wall system fulfills the need for a single layer air/vapor barrier and thermal wall assembly. It is simple, easy and fast to install using readily available materials and techniques. It delivers high R-value and moisture resistance for long-term insulation performance and an effective air barrier as evidenced by the results of ASTM E2357 testing. The is the new standard for insulating brick and block cavity wall assemblies. * Model based on the method outlined in the ASHRAE Handbook of Fundamentals. 8 UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 8

9 For Technical Information: BLUE (2583) For Sales Information: THE DOW CHEMICAL COMPANY. Dow Building Solutions. 200 Larkin. Midland, MI NOTICE: No freedom from any patent owned by Dow or others is to be inferred. Because use conditions and applicable laws may differ from one location to another and may change with time, Customer is responsible for determining whether products and the information in this document are appropriate for Customer s use and for ensuring that Customer s workplace and disposal practices are in compliance with applicable laws and other government enactments. The product shown in this literature may not be available for sale and/or available in all geographies where Dow is represented. The claims made may not have been approved for use in all countries or regions. Dow assumes no obligation or liability for the information in this document. References to Dow or the Company mean the Dow legal entity selling the products to Customer unless otherwise expressly noted. NO EXPRESS WAR- RANTIES ARE GIVEN EXCEPT FOR ANY APPLICABLE WRITTEN WARRANTIES SPECIFICALLY PROVIDED BY DOW. ALL IMPLIED WARRANTIES INCLUDING THOSE OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY EXCLUDED. STYROFOAM Brand Extruded Polystyrene Foam Insulation CAUTION: This product is combustible. Protect from high heat sources. A protective barrier or thermal barrier may be required as specified in the appropriate building code. For more information, consult MSDS, call Dow at BLUE (2583) or contact your local building inspector. In an emergency, call in the U.S. or in Canada. Dow Polyurethane Foam Insulation and Sealants CAUTION: When cured, these products are combustible and will burn if exposed to open flame or sparks from high-energy sources. Do not expose to temperatures above 240ºF (116ºC). For more information, consult MSDS, call Dow at BLUE (2583) or contact your local building inspector. In an emergency, call in the U.S. or in Canada. GREAT STUFF PRO sealant and adhesive products contain isocyanate and a flammable blowing agent. Read the label and Material Safety Data Sheet carefully before use. Eliminate all sources of ignition before use. Wear long sleeves, gloves, and safety glasses or goggles. Provide adequate ventilation or wear proper respiratory protection. Contents under pressure. GREAT STUFF PRO Gun Cleaner is flammable and contains acetone and propane. Read the label and Material Safety Data Sheet carefully before use. Eliminate all sources of ignition before use. Wear gloves, and goggles or safety glasses. Provide adequate ventilation or wear proper respiratory protection. Contents under pressure. WARNING: Rigid foam insulation does not constitute a working walkable surface or qualify as a fall protection product. Building and/or construction practices unrelated to building materials could greatly affect moisture and the potential for mold formation. No material supplier including Dow can give assurance that mold will not develop in any specific system. Printed in U.S.A. Form No MCK McKAY UNITED STATES. COMMERCIAL TECHNICAL INFORMATION 9