Technical Information for ProBlock Masonry Units ASTM C-90 Compliance

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1 Technical Information for ProBlock Masonry Units ASTM C-90 Compliance Concrete masonry units (CMU) had not changed much since 1931 with the original publication of ASTM C90, Standard Specification for Hollow Loadbearing Concrete Masonry Units, until 2011, with ASTM C b, which allows for, but does not require, a unit s webs to be configured differently. As a result, CMU designs may be altered in order to utilize fewer raw materials in production, reduce unit weight and/or increase energy efficiency of concrete masonry construction. ASTM C90 changed from requiring a minimum web thickness to requiring a minimum web area of 6.5 square inches per square foot of face area. No longer are manufacturers required to have three 1 thick webs on 8 block; instead an 8x8x16 block could have one web as thin as 0.75 and still meet ASTM C90 s new minimum web area requirements. Johnson Concrete s ProBlock utilizes thinner webs and has an open end to increase energy performance and improve mason productivity and safety. The web area of the 8 and 12 inch ProBlock Energy Max is about 13.8 in 2 /ft 2 which meets the new C90 requirements. ProBlock comes in an Energy Max version which has higher thermal efficiency and slightly reduced weight compared to the 2 hour ProBlock version. The 8 inch 2 hour ProBlock has an equivalent thickness of about 3.7 inches and is produced using only ESCS lightweight aggregates. The unit configuration and density meets the 2 hour fire rating requirements of both the International Building Code and North Carolina Building Code. ProBlock meets ASTM 90 requirements for compressive strength when tested as a whole unit or when tested as a closed cell unit per ASTM C140. The compressive strength of ProBlock is the same as with the standard lightweight unit produced by Johnson Concrete. Johnson Concrete is happy to provide project specific R value calculation based on actual grout spacing, grout material selection and ProBlock selected. Johnson Concrete can also assist in determination of STC, heat capacity, net and average section properties, fire rating and grout estimation for projects using the ProBlock. The following sections offer more detail about some of the features of the ProBlock.

2 ProBlock Insulated Wall System: Energy Performance R-value is the measure of thermal resistance used in the building and construction industries. Higher R-value equates to increased resistance to heat flow. R-value measures the ratio of the temperature difference across an insulator (concrete masonry wall) and the heat flux (heat transfer per unit area per unit time). The key to maximizing whole-wall R-values of concrete masonry walls is minimizing thermal bridges within the concrete masonry units, and increasing the thermal resistance of the concrete used to produce concrete masonry units. Lightweight concrete is ideal for highest thermal performance concrete masonry wall assemblies. Whole-wall R-values for ProBlock walls are much greater than conventional 3-web concrete block walls. The increase achieved by injecting aminoplast foam insulation is up to 264% greater than what is possible with normal weight concrete masonry walls injected with the same aminoplast foam injection. The table below illustrates the exceptional thermal performances that can be achieved by specifying ProBlock / Core Foam Masonry Foam Insulation Wall Systems. 8x8x16 12x8x16 Density R Value* Increase** ProBlock Energy Max 85 pcf % ProBlock 105 pcf % NW ProBlock 130 pcf % ProBlock Fire Rated 85 pcf % Regular LW Block 105 pcf % Regular NW Block 130 pcf % ProBlock Energy Max 85 pcf % ProBlock 105 pcf % NW ProBlock 130 pcf % ProBlock Fire Rated 85 pcf % Regular LW Block 105 pcf % Regular NW Block 130 pcf % *Filled with R 4.60/inch injected Core Foam Masonry Foam Insulation ** Compared to Standard Normal Weight Concrete Masonry Units R-values of ProBlock walls insulated with aminoplast foam compare favorably with those insulated with closed-cell polyurethane foam. Because aminoplast foam flows within the wall, all of the nooks & crannies get filled. Polyurethane foam expands rather than flows; thus, many more holes must be drilled & patched, expanding foam tends to bridge small openings to leave voids, and polyurethane foam simply costs far more than aminoplast foam insulation. For these reasons: better performance and faster installation at a lower cost, Core Foam Masonry Foam R-4.60/inch is the better choice for injecting ProBlock and ProBlock Energy Max

3 walls vs. closed-cell polyurethane foam R-5.91/inch. The table below illustrates how closely whole-wall R-values track one another no matter the type of foam used to fill corecells of ProBlock walls. Aminoplast Foam vs. R-Values w/foam Insulation Polyurethane Foam Size Block Type Density R-4.6/in. R-5.91/in. ProBlock Energy Max 85 pcf ProBlock 105 pcf x8x16 NW ProBlock 130 pcf Regular NW Block 130 pcf ProBlock Energy Max 85 pcf ProBlock 105 pcf x8x16 NW ProBlock 130 pcf Regular NW Block 130 pcf Demonstrating Energy Code Compliance Using COMCheck: When using COMCheck for energy code compliance demonstration analysis, the U-value for the wall assembly should be used in the other mass wall section of the program. Below are U-values that can be used in this portion of the program. Net U-Value Foam Insulated with Various Foam 32 X 48 X 48 X 72 X Block Type Density R/Inch x8x16 ProBlock Energy Max 85 pcf ProBlock 105 pcf x8x16 ProBlock Energy Max 85 pcf ProBlock 105 pcf In the COMCheck program, when the other mass section is used, the heat capacity (HC) of the wall assembly must be used in conjunction with the U-value. The tables below show HC for various ProBlock Insulated Wall System assemblies. 8 inch ProBlock 12 inch ProBlock Weight/SF HC Weight/SF HC Ungrouted Ungrouted X X X X X X X X X X

4 R and U Values of ed ProBlock Insulated Wall System to use with COMcheck The tables below show the calculated R and U values of 8 and 12 ProBlock, grouted at various spacing. The R and U values are calculated with the empty cells of the units filled with R-4.6/inch masonry foam insulation by cfifoam, Inc. The ProBlock Insulated Wall System is calculated using 3/8 mortar joints and normal weight concrete grout. Air films on both sides of the wall were included in tabulating these R and U values. The seriesparallel (also called isothermal planes) calculation method is used in the calculations. 8 inch ProBlock Energy Max- 85 pcf Block Density Horizontal (Center to Center) 8 inch ProBlock Energy Max- 105 pcf Block Density Horizontal (Center to Center) Vertical (Center to Center) No R U R U R U R U R U R U Vertical (Center to Center) No R U R U R U R U R U R U Note: The IECC does not prohibit using integral masonry foam insulation in CMU construction. The Prescriptive Compliance path is presented in Section 502. Section clarifies that insulation filling the cells of CMU walls is not considered cavity insulation per Table (1). The insulating value of foam insulation filling the CMU's is taken into account using the U-factor Table, Table The U- values shown in these tables are for use with COMcheck in lieu of the default U-value representing granular loose-fill insulation. Neither the COMcheck compliance path, nor the Total Building Performance path of Section 507 prohibits using masonry foam insulation in the core-cells of CMU wall construction. NCMA TEK 6-4B (2012) provides additional guidance for architects and engineers who choose to demonstrate energy conservation code compliance by taking advantage of the trade-offs available to those who choose to use COMcheck compliance software. COMcheck can be downloaded free of charge from:

5 12 inch ProBlock Energy Max-85 pcf Block Density Horizontal (Center to Center) 12 inch ProBlock Energy Max- 105 pcf Block Density Horizontal (Center to Center) Vertical (Center to Center) No R U R U R U R U R U R U Vertical (Center to Center) No R U R U R U R U R U R U

6 Foundation Load Reduction using ProBlock ProBlock masonry units are designed with less material and are produced using ESCS lightweight aggregates. The combination of the reduced material and ESCS lightweight aggregates significantly reduce the weight of the units in the wall. 12 inch Block 20' x 200' wall example Block Type Weight/ LF Decrease ProBlock % Ungrouted Standard X 48 ProBlock % Standard X 48 ProBlock % Standard X 48 ProBlock % Standard X 72 ProBlock % Standard X 72 ProBlock % Standard 1495 The weight per linear foot of walls made with ProBlock can be reduced by up to 52%. This foundation load reduction can help minimize foundation requirements especially where poor foundation soils are present. Section Properties of ProBlock 8 inch Block 20' x 200' wall example Block Type Weight/ LF Decrease ProBlock % Ungrouted Standard X 48 ProBlock % Standard X 48 ProBlock % Standard X 48 ProBlock % Standard X 72 ProBlock % Standard X 72 ProBlock % Standard 1020 The charts below show the horizontal cross section (masonry spanning vertically) and vertical cross section (masonry spanning horizontally) properties of ProBlock with ¾ inch webs and various grout spacing. The ProBlock and typical masonry units have the same net area and similar but slightly lower average areas. The 12 inch ProBlock has a bigger average area difference than the 8 inch ProBlock.

7 Horizontal Section Properties 8 in ProBlock A n (in 2 /ft) I n (in 4 /ft) S n (in 3 /ft) A avg (in 2 /ft) I avg (in 4 /ft) S avg (in 3 /ft) r avg (in) no grout in ProBlock A n (in 2 /ft) I n (in 4 /ft) S n (in 3 /ft) A avg (in 2 /ft) I avg (in 4 /ft) S avg (in 3 /ft) r avg (in) no grout Vertical Section Properties 8 in A block A n (in 2 /ft) I n (in 4 /ft) S n (in 3 /ft) A avg (in 2 /ft) I avg (in 4 /ft) S avg (in 3 /ft) r avg (in) no grout in A Block A n (in 2 /ft) I n (in 4 /ft) S n (in 3 /ft) A avg (in 2 /ft) I avg (in 4 /ft) S avg (in 3 /ft) r avg (in) no grout

8 In the absence of an E119 fire test on a specific masonry unit design, fire ratings are determined using the Equivalent thickness method. Using the equivalent thickness method for fire rating determination 8 inch ProBlock has can achieve a 2 hour fire rating using the 2 Hour version and 90% or greater by volume lightweight aggregate. The following table shows the fire ratings achieved by the equivalent thickness method. Fire Rating with ProBlock

9 Fire Rating of ProBlock ACI 216 Fire Rating Analysis ProBlock 8 inch 12 inch 2 hour ProBlock ProBlock 1.3 web ProBlock Equivalent Thickness (in)* Aggregate composition Fire Rating Hours 100% ESCS % ES 10% NW % ES 20% NW % ES 30% NW % ES 40% NW % ES 50% NW % ES 60% NW % ES 70% NW % ES 80% NW % ES 90% NW % NW

10 Use Comparison ProBlock Vs Regular Units The ProBlock has one fewer web than regular masonry units and is designed to easily go around reinforcing steel. The ProBlock grouted cells will be able to resist moisture penetration better than regular grouted units. Open head joints can be a primary source of water infiltration in masonry walls. The ProBlock eliminates open head joints in grouted cells, minimizing water infiltration inch Block 20' x 200' wall example Block increase additional Type yd 3 yd 3 yd 3 per ProBlock Standard ProBlock Standard ProBlock 8.87 Standard ProBlock 6.65 Standard ProBlock 5.91 Standard Since the block has one fewer webs it will take additional grout to fill the grouted cells. The area of the removed web and the area of the head joint have to be filled with grout. The amount of the extra grout is small at typical grout spacing. The following charts show the grout required for a 20 foot high 200 foot long wall with various grout spacing. 12 inch Block 20' x 200' wall example Block Type yd 3 Increase yd ProBlock Standard ProBlock Standard ProBlock Standard ProBlock Standard 9.67 ProBlock Standard Additional yd 3 per The 12 inch ProBlock has approximately 25 percent less material than regular 12 inch masonry units. The 12 inch ProBlock has 1 ¼ inch face shells and thinner webs. The amount of grout required to fill in the 12 inch ProBlock is higher than it is with the 8 inch ProBlock, but the extremely light weight and associated production savings along with the reduced water infiltration potential make the 12 inch ProBlock the choice of masons.

11 Since the open end of the ProBlock allows block to be placed around reinforcing steel and does not require going over the steel, longer pieces of steel may be used. The net result of using longer pieces of steel is steel reduction. The required length of lap or development is determined according to the design procedure used (allowable stress design or strength design). The length of the lap varies by code and design method, but the longer the individual pieces of reinforcing you use the less steel you need to account for the required overlap. The chart to the right is for a 20 foot high wall and demonstrates the reduction in Steel Lift Length (ft) Wall Height 20 Feet reinforcing steel when using 8 and 12 foot sections steel compared to using 4 foot spans. The 4 foot lift length of #5 steel used in the chart is 6 feet 2 inches due to the lap length. These steel reductions can result in savings that offset a large portion of the additional grout cost using ProBlock. Linear Feet of Steel Comparison 4+ Lap 8+ Lap Reduction 12+ Lap Reduction Bar size Lap Length IBC 2006 # inches % % # inches % % # inches % % (in) Steel Lift(ft) Wall Length 200 Feet -Wall Height 20 Feet feet 8 feet Savings* 4 feet 8 feet Savings* 4 feet 8 feet Savings* # $ $ $37 # $ $ $71 # $1, $ $168 Steel cost $0.50 per pound

12 STC STC is roughly the decibel reduction in noise a partition can provide, abbreviated 'db'. The db scale is a logarithmic one and the human ear perceives a 10dB reduction in sound as roughly halving the volume - a 40 db noise subjectively seems half as loud as a 50 db one. If an 80dB sound on one side of a wall/floor/ceiling is reduced to 50dB on the other side, that partition is said to have an STC of 30. The International Building Code contains requirements to regulate sound transmission through interior partitions separating adjacent dwelling units and separating dwelling units from adjacent public areas, such as hallways, corridors, stairs or service areas. Partitions serving the above purposes must have a sound transmission class (STC) of at least 50 db STC is calculated as 20.5 x W The weight per ft 2 of wall is the key factor that affects the STC rating of a wall. There are some other factors which may affect the STC rating of a wall assembly as well and they are: ASTM E90 test results have shown that STC ratings improve by 4 db when one (1) side of Concrete Masonry Walls receives two (2) coats acrylic-latex paint ( Sound Transmission Loss Through Concrete and Concrete Masonry Walls, Portland Cement Association, ) Foam Injection can add up to 6 db (Citifoam Info Sheet) For more information on STC ratings see NCMA TEK Note 13-1C (Sound Transmission Class for Concrete Masonry Walls). OITC is a standard used for indicating the rate of transmission of sound between outdoor and indoor spaces in a structure. It is based on the ASTM E-1332 Standard Classification for the Determination of Outdoor Indoor Transmission Class. 8 Inch ProBlock Ungrouted Block Type Weight/SF STC 8 inch ProBlock STC w/ Paint STC w/ Foam STC w/ Foam and paint ProBlock Standard OITC 12 Inch ProBlock Ungrouted Block Type Weight/SF STC STC w/ Paint STC w/ Foam STC w/ Foam and paint ProBlock Standard OITC

13 The ProBlock Story ProBlock is a patent pending concrete masonry unit designed and marketed by Johnson Concrete Company. It is the final result of multiple collaborations between Johnson Concrete s engineers, block masons and architects. The designs genesis dates back to October 2010 when Johnson Concrete hosted a meeting with masons and architects to discuss the future of concrete masonry and what block producers could do to improve the market. From this meeting Johnson Concrete took key points from the masons and architects and started working on products to fit the needs of the industry. The masons and architects highlighted the need for innovative masonry products that met the following requirements: Masons 1. It has to light, not just a little lighter but light enough to make a real difference 2. You have to be able to lift it with one hand in order to keep the production level up 3. It has to be well balanced and easy to lay for the mason in the field Architects 1. It needs to be more energy efficient to deal with the new energy codes 2. It needs to offer design flexibility 3. It has to be cost competitive 4. It needs to shorten construction schedules 5. It has to meet fire rating requirements The first few attempts Johnson Concrete made to create units that would fit these needs met with only marginal success. Johnson Concrete created a 12 inch high Prodigy block and a 24 inch long Labor Saver. These units never took off because they did not address all the needs of the masons or architects. When the ASTM C90 standard changed from requiring 2 ¼ inches/foot minimum equivalent web thickness to requiring 6.5 in 2 /ft 2 normalized web area, Johnson Concrete saw the opportunity to develop a product that could change the masonry industry. The design of ProBlock was centered on the things we learned in those early meetings. We worked to develop the lightest, most balanced easy to lay and best energy performance block possible. Some other general industry concerns arose during the development stage of the ProBlock that we addressed through engineering or trial and error. We had to have a block that: 1. Would be effective in partial grouted construction applications 2. That could be made easily and quickly on existing block machines 3. That would maintain dimensional tolerances through production 4. That was strong enough to make it to the jobsite without increased chips or cracks.

14 When the design work and testing was complete, the ProBlock was so much different than anything else on the market we decided to apply for a patent on the product and promote it throughout the United States. The ProBlock is everything we set out to make it plus some. The weight is amazing low, it is easy to make, easy to handle and lay in the wall. The R-value increases with the ProBlock especially when used in conjunction with a material like Core Foam Masonry foam Insulation are outstanding. Masons who have used the block have found tremendous production rate increases and actively look for more opportunities to use it on their projects. The ProBlock is backed by a strong technical support and engineering team. Johnson Concrete is currently working on E119 fire testing and thermal measurements using the ProBlock to better take advantage of the properties of the block. Johnson is committed to making ProBlock the industry standard for high performance masonry wall systems. The ProBlock offers benefits to everyone from the block producer to the mason to the owner/architect. It is a great solution for energy, productivity, safety and profitability. Contact: