Exterior Portland Cement Plaster Assemblies

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Exterior Portland Cement Plaster Assemblies

  1. 1. TECHNICAL SERVICES INFORMATION BUREAU
  2. 2. Exterior Plaster Wall and Ceilings, Fire-Resistive & Drywall Assemblies: Presented by the Technical Services Information Bureau . . . Darin Coats Bryan Stanley M ichael M . Logue
  3. 3. WESTERN WALL & CEILING CONTRACTORS ASSOCIATION TECHNICAL SERVICES INFORMATION BUREAU
  4. 4. •Administrative Functions •Multi Employer Bargaining Agent •Trustee of Pension, Health & Welfare •Apprenticeship Programs •Member Benefits •Union Contract Administrator •Technical Services •Trade Promotion •Trade Education •Industry Standards •Field Inspections and Reports •Code Development •Technical Committees and Councils •Detailing – Spec Review •Preconstruction – Mock Ups
  5. 5. Who we are … a little history  WWCCA / TSIB can be traced back to 1929, when we were called the Contracting Plasterers’ Association Southern California CPASC.
  6. 6. 1929 – 1988 … The original state association board members
  7. 7. Materials suppliers and manufacturers have long been an integral part of the Association
  8. 8. Back then plaster was applied over strips of wood called “wood lath”
  9. 9. Advancements in manufacturing brought new materials for lathing Early metal lath provided better keying for the plaster scratch coat
  10. 10. As the industry grew, so to did the need for technical services. Walt Pruter started the Plastering Information Bureau in 1952 Walt Pruter Clyde Bell Jim Rose Harold McKeller Walt Pruter, was a WWII carrier pilot, an architect from the Illinois Institute of Technology, and an architectural representative from United States Gypsum prior to his career with the Bureau
  11. 11. Twelve years later Walt turned over the Plastering Information Bureau to J.R. “Dick” Gorman Dick Gorman, was an Army Captain and an Architect from Rice University before he came to us from Kaiser Gypsum
  12. 12. Dick was instrumental in the development of the Data Guide and Reference Spec’s, and the original stucco textures and finishes brochure …
  13. 13. In the 50’s, southern California began a housing boom and ushered in the era of the tract home. Stucco (exterior) and Gypsum Plaster (interior) were used extensively.
  14. 14. The advent of the tract home in the 50’s put many Southern California plastering contractors on the map. Past Presidents Geo. M. Raymond C. B. Scott
  15. 15. Commercial and Residential markets continued to grow into the 1960’s and plaster was there to meet the growing demands of designers
  16. 16. As the complexity of structures increased, so to did the need for a reliable, accurate source of information. In 1977, Walt Pruter, Clay Johnson and Sam Jaffe published the Plaster/Metal Framing Systems/Lath Manual. First Edition Second Edition
  17. 17. In 1987, Dick Gorman, Walt Pruter, Jim Rose and Sam Jaffe published the 3rd edition of the manual, which now contained drywall technical information, and called it the Drywall and Plaster Systems Manual – AKA “The Manual”
  18. 18. TSIB Staff and Consultants  1952 - 2008 Walt Pruter  1964 J.R. “Dick” Gorman – Senior Consultant, field inspections from LA – to San Luis Obispo  2000 Michael Logue – Director - Oversees all Technical Services. ASTM/ICC/ACI/AIA/AWCI/FCA/DWFC/WCWCI  2002 Darin Coats – Technical Advisor – Specializes in Drywall and Drywall Finishing, and Ceramic Tile Bases DWFC/CTIOA/WCWCI  2005 Bryan Stanley – Technical Advisor – Specializes in Acrylic and EIFS – Runs the San Diego membership meetings – CSI/AIA/WCWCI
  19. 19. TSIB – What we do  Trade Promotion  Trade Education – AIA Accredited Continuing Education  Research and Development of Industry Standards  Third Party Field Inspections and Reports  Code Development  Technical Committees and Councils  Architectural Consulting - Details and Specifications  Preconstruction and Mock-up meetings  Contractor – Architect – Inspector Liaison
  20. 20. Trade Promotion 2002 Construction Specifications Institute Annual Trade Show – Las Vegas, NV
  21. 21. Education
  22. 22. Research and Development of Industry Standards  Application of lath  Lath trims and screeds  Suspended ceilings  Plaster mixes  Weather-Resistive Barriers  Plaster Over Masonry – Direct Applied  Metal Stud Framing  Gypsum Sheathing  Fire Rated Assemblies  Drywall Finishing
  23. 23. Third Party Field Inspections 100_2754.mov
  24. 24. Code Development  California Building Standards Commission  International Code Council  ASTM  ANSI
  25. 25. Technical Committees and Councils  ASTM C -11  American Concrete Institute –  Steel Stud Manufacturers Association  AWCI Technical Committees  Portland Cement Association  Drywall Finishing Council  Western Conference of Wall & Ceiling Institutes  Ceramic Tile Institute of America
  26. 26. Plans and Specifications Reviewing  Cedars Sinai – North Care Tower  White Memorial  Arcadia Methodist Tower  Hoag – Newport Beach, CA  Twin Cities – Templeton, CA  Santa Barbara Hospital  Kaiser Sand Canyon  Kaiser Panorama City  Orange County Performing Arts Center  Pierce College
  27. 27. PORTLAND CEMENT PLASTER
  28. 28. Plaster is an ancient material, durable, inexpensive and versatile material...
  29. 29. HISTORIC PLASTER OVER MASONRY –OLD MILL - SAN MARINO, CA
  30. 30. HISTORIC PLASTER OVER MASONRY –OLD MILL - SAN MARINO, CA
  31. 31. SIMULATION OF AFRICAN NATIVE MUD PLASTERING – SAN DIEGO WILD ANIMAL PARK
  32. 32. SIMULATED STONE CASTLE – MODIFIED PLASTER SYSTEM – LEGOLAND
  33. 33. SIMULATED STONE FIREPLACE – MODIFIED PLASTER SYSTEM – LEGOLAND
  34. 34. EXTERIOR PLASTER WALL AND CEILING SYSTEMS - PROGRAM OUTLINE •MASONRY SUBSTRATES •WOOD FRAMING •METAL STUD FRAMING •PLASTER CEILINGS •EXTERIOR GYP. SHEATHING •WEATHER-RESISTANT BARRIERS •FLASHING •LATH AND ACCESSORIES •SCRATCH & BROWN • FINISHES • CONTINUOUS INSULATION
  35. 35. MASONRY
  36. 36. Cast-in-Place Concrete / CMU
  37. 37. Cast-in-P lace Concrete  Cured 28 days – ACI 308R  Clean  ¼ in 10’
  38. 38. Cast-in-P lace Concret
  39. 39. Apply lath and 3 coat when matching fram ed and lathed w alls If Direct Applied, apply bonder evenly Document Point / Patch by others
  40. 40. Cast-in-Place Concrete Bond Breakers “A1.6.2 Form release compounds shall be compatible with plaster or be completely removed from surfaces to receive plaster.” - ASTM C 926 Sodium Silicate bond breaker will dissipate and can be direct applied with plaster. Petroleum based, oil / paraffin etc. cannot be direct applied over.
  41. 41. M EDI UM DENSI TY OVER LAY
  42. 42. Cast-in-place Concrete – DIRECT APPLY
  43. 43. Concrete Masonry Units Yorba Linda High School – Perlite Plastering 2009
  44. 44. CM U  Joints Cut Flush  90 % Loaded  Fully Cured  Clean  ¼ in. Alignment
  45. 45. CONCRETE MASONRY UNITS – DIRECT APPLY
  46. 46. WOOD
  47. 47. Wood
  48. 48. Wood •Locate CJ - Vertical backing
  49. 49. Wood •Sill Plate Offset
  50. 50. Wood •Plywood Gaped 1/8 in.
  51. 51. SPACER NAIL – NO 1/8” GAP
  52. 52. Wood •2 Layers grade “D”
  53. 53. ROLL FORMED METAL
  54. 54. Roll Formed Steel
  55. 55. Roll Formed Steel •16 Gage - .0549” •16” O.C. Vertical •13 ½” – 12” Ceilings •L/360 •ASTM C 1063 (NLB) – ¼ in. – 10’ •ASTM C 1007 (LB) – 1/8 in. – 10’
  56. 56. Steel Framing Construction Basics Member Nomenclature
  57. 57. A primer on Nomenclature  Steel framing industry moving away from using the term “gauge” to refer to thickness of material. •Thickness expressed in “mils”: •One mil = 1/1000 inch. •Basic information is on inside front cover of SSMA catalog.
  58. 58. Standardization 600 S 162 - 54 6” member Stud or Joist 1-5/8” Min. base metal depth with Lips Flange thickness in mils (1.625”) (0.054” = 54 mils) • Steel Members are Standardized Using a Universal Designation System
  59. 59. Member Depth:  Measured on studs: outside flanges.  Measured on tracks: inside flanges.
  60. 60. AT LEAST ONE CREATIVE MIND EVEN LOOKED BEYOND CONVENTIONIAL MATERIALS FOR THEIR PLASTER SUBSTRATE…
  61. 61. …CHAIN LINK FENCE !! !! ! CHAIN LINK FENCE !
  62. 62. 8 or 9 Gage Hanger Wire – 3 ½’ O. C. 1 ½” CRC Main Runners – 3 ½’ O.C. ¾” CRC Cross Furring – 13 ½” O.C. 3.4 lb/sy Exp. Metal Lath – tie wire Control Joints – 100 SF – Provide Backing Good plaster starts w ith good lathing
  63. 63. P laster Ceilings Suspended Iron / Lath / Tie Wire No Rib Lath No Sheathing / WRB DEFS – a good substitute
  64. 64. SUSPENDED CEILINGS SADDLE TIES
  65. 65. DON’T USE SHEATHING AND WEATHER-RESISTANT BARRIERS
  66. 66. PLASTER CEILINGS
  67. 67. EXTERIOR GYP. SHEATHING - METAL STUD FRAMING
  68. 68. WHY USE IT? •PROVIDES BACKING AND UNIFORM FLATNESS •ELIMINATES MOST VERTICAL LINES •PROVIDES ATTACHMENT FOR BUILDING PAPER •REQUIRED FOR RATED CONSTRUCTION
  69. 69. EXTERIOR SHEATHING - METAL STUD FRAMING WHY USE IT? •PROVIDES BACKING AND UNIFORM FLATNESS
  70. 70. EXTERIOR SHEATHING - METAL STUD FRAMING WHY USE IT? A: ELIMINATES MOST VERTICAL LINES
  71. 71. EXTERIOR SHEATHING - METAL STUD FRAMING WHY USE IT? A: MAKES DEEP COLORS MORE CONSISTENT
  72. 72. PROVIDES ATTACHMENT FOR BUILDING PAPER
  73. 73. EXTERIOR SHEATHING WHY USE SHEATHING? •PUTS GYPSUM IN THE PLASER SYSTEM FOR RATED SYSTEMS
  74. 74. WEATHER-RESISTING BARRIER The IBC & CBC use the term “W eather-Resisting Barrier“ in the definition of “Ex terior W all Covering “ (§1402) A Weather-Resisting Barrier is comprised of one or more Water-Resistive Barriers W RB The WRB’s work together to create a weather-resistant exterior wall envelope (§ 1403.2)
  75. 75. What does the WRB do?
  76. 76. In a plastered wall (a drainage system) the WRB is the primary means of waterproofing
  77. 77. BUILDING PAPERS TYPES OF COMMONLY USED BUILDING PAPERS  GRADE “B”  GRADE “D”  SYNTHETIC OR NON-PAPER
  78. 78. Paperback Lath
  79. 79. GRADE “B”  WATER PENETRATION RESISTANCE - RATED AT 16 HOURS  U.V. SENSATIVE - TENDS TO SHRINK AND WRINKLE  NOT VAP OR P ERM EABLE AND CANNOT BE USED W I TH W OOD-BASED SHEATHI NG
  80. 80. GRADE “B”
  81. 81. GRADE “B”
  82. 82. GRADE “D”  10 TO 60 MINUTE RATED  FOR USE OVER WOOD-BASED SHEATHING IN TWO LAYERS  ALLOWS VAPOR PERMABILITY  RESISTS U.V. DEGRADATION BETTER THAN GRADE “B”
  83. 83. GRADE “D”
  84. 84. GRADE “D”
  85. 85.  CLASSIFIED GRADE “D”  SUPERIOR PRODUCT IN AREA OF HIGH WINDS - RESISTS TEARING
  86. 86. FELT  Do not use #15 or 30# felt for a weather resistant barrier! Felt is a roofing product that is no longer used in wall and ceiling assemblies.
  87. 87. FLASHING AND SEALANTS
  88. 88. SEALANTS/CAULKING & BACKER
  89. 89. # 40 TWO-PIECE EXPANSION JOINT XJ 15 ONE-PIECE CONTROL JOINT
  90. 90. #40 TWO PIECE VERTICAL JOINT
  91. 91. LATHING ACCESSORIES Control Joint: XJ-15
  92. 92. LATHING ACCESSORIES Inside Corner Joint: No. 30
  93. 93. LATHING ACCESSORIES No. 5 Drip Mould
  94. 94. LATHING ACCESSORIES CASING BEADS - PLASTER GROUNDS Short Flange No. 66 Expanded Flange No. 66
  95. 95. LACK OF CASING BEAD: NO DEFINITIVE SEPARATION TO DISSIMILAR MATERIAL
  96. 96. LATHING ACCESSORIES CASING BEADS - PLASTER GROUNDS LACK OF CASING BEAD: RESULTANT CRACKING
  97. 97. LATHING ACCESSORIES CASING BEADS - PLASTER GROUNDS GOOD USE OF CASING BEAD
  98. 98. LATHING ACCESSORIES CASING BEADS - PLASTER GROUNDS
  99. 99. LATHING ACCESSORIES CASING BEADS - PLASTER GROUNDS
  100. 100. LATHING ACCESSORIES OUTSIDE CORNER REINFORCEMENT Corner Aid Corner Bead
  101. 101. CORNER AID OUTSIDE CORNER REINFORCEMENT
  102. 102. CORNER BEAD OUTSIDE CORNER REINFORCEMENT
  103. 103. LATHING ACCESSORIES Foundation Weep Screed PER ASTM C 1063 - 7.11.5
  104. 104. UBC Reference: 2506.5 Application of Metal Plaster Bases A minimum 0.019-inch (.48 mm) (No. 26 galvanized sheet gage) corrosion-resistant weep screed with a minimum vertical attachment flange of 3 1/2 inches (89 mm) shall be provided at or below the foundation plate line on all exterior stud walls. The screed shall be placed a minimum of 4 inches (102 mm) above the earth or 2 inches (51 mm) above paved areas and shall be of a type that will allow trapped water to drain to the exterior of the building. The weather-resistive barrier shall lap the attachment flange, and the exterior lath shall cover and terminate on the attachment flange of the screed.
  105. 105. PLASTER BASES – TYPES OF LATH
  106. 106. Expanded Metal ASTM C847
  107. 107. WOVEN WIRE ASTM C1032
  108. 108. WELDED WIRE - NO PAPER ASTM C933
  109. 109. WELDED WIRE WITH PAPER – ASTM C933
  110. 110. Scratch & Brown  Cement  Lime  Sand  Water
  111. 111. NEGATIVE characteristics of Portland Cement Based Plaster •Non-Structural •Brittle •Good Compressive Strength •Poor Tensile Strength •Shrinks During Hydration •Prone to Cracking
  112. 112. POSTIIVE characteristics of Portland Cement Based Plaster •Water Permeable (water management system) •Moisture saturates approximately 1/16” – 1/8” per hour during heavy precipitation •Water needs a pathway back out of the plaster systems •Walls breath instead of trapping water
  113. 113. PORTLAND CEMENT “SCRATCH”
  114. 114. PORTLAND CEMENT “SCRATCH” NOTCHED TROWEL
  115. 115. PORTLAND CEMENT “SCRATCH” SCARAFIER/COMB
  116. 116. Moist cure fresh scratch coat to achieve 48 hours of continuous cement hydration “8.1 Sufficient time between coats shall be allowed to permit each coat to cure or develop enough rigidity to resist cracking or other physical damage when the next coat is applied.” - ASTM C926
  117. 117. PORTLAND CEMENT “BROWN”
  118. 118. PORTLAND CEMENT “BROWN”
  119. 119. Moist cure fresh brown coat to achieve 48 hours of continuous cement hydration …
  120. 120. Allow brown to dry cure for an additional 5 days Summary, Average basecoat application: Apply scratch day 1 Moist cure days 2-3 Apply brown day 4 Moist cure days 5-6 Dry cure days 7-11 Total 11 days
  121. 121. FINISH OPTIONS  INTEGRALLY COLORED CEMENT & ACRYLIC – Float Finish – Dash Finish – Troweled Finish
  122. 122. FINISH OPTIONS  COMMERCIAL TEXTURES RECOM M ENDED CHOI CES
  123. 123. Fine Sand Float
  124. 124. Med. Sand Float
  125. 125. Heavy Sand Float
  126. 126. Light Dash
  127. 127. Med. Dash
  128. 128. Heavy Dash
  129. 129. Tunnel Dash
  130. 130. K.D. Dash
  131. 131. FINISH OPTIONS  COMMERCIAL TEXTURES ACCENT TEXTURES
  132. 132. MARBLE- CRETE
  133. 133. COMBED SCRAPED
  134. 134. FINISH OPTIONS  RESIDENTIAL TEXTURES
  135. 135. Light Lace Heavy Lace
  136. 136. SPANISH ARIZONA
  137. 137. ROCK-N-ROLL FRIEZE
  138. 138. FINISH OPTIONS  THEME FINISHES
  139. 139. SIMULATED TIMBER
  140. 140. SIMULATED BRICK
  141. 141. SIMULATED TRAVERTINE
  142. 142. FINISH OPTIONS  COMMERCIAL/RESIDENTIAL TEXTURES P OOR CHOI CES
  143. 143. CAT FACES
  144. 144. CAT FACES IN CRITICAL LIGHT
  145. 145. SANTA BARBARA STD. SMOOTH
  146. 146. HIGHLY LIKELY TO CRACK EXCESSIVELY
  147. 147. •UNLIMITED COLORS 100% ACRYLIC FINISH •MAR & WEATHER RESISTANT ACRYLIC FINISH
  148. 148. DESIGNING W/ FOAM “PLANT-ON” SHAPES
  149. 149. DESIGNING W/ FOAM “PLANT-ON” SHAPES
  150. 150. RECOMMEDED USE OF FOAM … Off the Ground & Away from “Traffic
  151. 151. …POOR USE OF FOAM At Ground Level
  152. 152. Efflorescence Refers to deposits of soluble compounds (salts) carried by water onto the surface of porous masonry or hydraulic cementitious materials.
  153. 153. Efflorescence The process is very similar to your body sweating. During exercise, salts in your body are brought to the surface by the sweat your body produces to cool off. The sweat evaporates taking with it latent heat. The residual material is the white deposit you find on your gym clothes.
  154. 154. Efflorescence Efflorescence is not just limited to plaster …
  155. 155. Efflorescence .. it can appear on any porous, hydraulic, cementitious material …
  156. 156. Efflorescence Plaster is the most difficult surface to remove efflorescence from
  157. 157. Efflorescence It doesn’t always have to be white; it is often green, brown, or even black
  158. 158. EFFLORESCENCE Efflorescence can also flow unto the surface of non porous materials. It is often caused by precast elements with a horizontal top.
  159. 159. Efflorescence at cracks can give an indication of the amount of water flow reaching the drainage plane
  160. 160. EFFLORESCENCE Left untreated, it can accumulate into a quite a large amount of material
  161. 161. Efflorescence In nature, where time is measured in millions of years, efflorescence takes on a life form of its own …
  162. 162. EFFLORESCENCE
  163. 163. Efflorescence
  164. 164. Efflorescence Three (3) Conditions must exist simultaneously for efflorescence to develop: 1. Soluble salts must be present 2. Water must contact the salts to form a solution 3. The salt solution must have a path to migrate to a surface where the water can evaporate (precipitate out).
  165. 165. Efflorescence The most common type of efflorescence is calcium hydroxide, a soluble component of efflorescence. This is the type of efflorescence we refer to as “new bloom” and usually washes away with rain …
  166. 166. Efflorescence However, calcium hydroxide efflorescence reacts with air (absorbs carbon dioxide) and becomes calcium carbonate, which is not water soluble and does not was away with the rain.
  167. 167. Efflorescence HOW DO I GET THIS STUFF CLEANED UP?
  168. 168. www.tsib.org
  169. 169. Arizona California Nevada Oregon Washington Plastering Information Bureau San Francisco –San Mateo NortherN CaliforNia lath aNd Plaster Bureau
  170. 170. INTRODUCES
  171. 171. The following will change the way exterior walls are built
  172. 172. Energy Codes
  173. 173. JAN 1, 2010 • ONE YEAR DELAY •CA ENERGY ONLINE •ASHRAE 90.1
  174. 174. Thermal Shorts
  175. 175. Correction Factor, Effective RE ASHRAE Correction Factor 90.1 --- Effective R-value = R-value x Correction Factor The ASHRAE 90.1 correction factor considers the heat loss through the highly inefficient steel studs and is based on the R-value of the insulation used between the studs only.
  176. 176. California has 16 zones No relation to ASHRAE Zones Website in the Brochure
  177. 177. GOAL: Energy efficiency of 30% in the 2010 compared to the 2004 standard. net-zero energy buildings by 2030.
  178. 178. Rigid Foam - Why?
  179. 179. REMEMBER THE “R” VALUE LOST DUE TO THERMAL SHORTS? ASHRAE and the energy codes called and they w ant it back ! Cladding Neutral
  180. 180. The OBVIOUS CHOICE IS EIFS •CODE RECOGNIZED •PROVEN •READILY AVAILABLE
  181. 181. PROBLEM IS…MANY OWNERS WONT USE EIFS – WE NEED CODE COMPLIANT - 3-COAT CEMENT IN OUR MARKETS
  182. 182. HERE’S WHAT WE HAVE:
  183. 183. PWA 104 Cement plaster Over Foam  CODE – ASTM C-926 item 7.1.3 – “Portland Cement Plaster shall be applied on a metal base when the surface of solid backing consists of gypsum board, gypsum plaster, wood or rigid foam board type products”
  184. 184. General Design Recommendations ( All Stucco)  L/360 or stiffer  Vapor Permeable WRB  Plaster Mixes , ASTM C-926  16 inch OC framing - best perform ance
  185. 185. Mesh & Base “Lamina” OPTIONS 1. No Lamina - likely to crack more 2. Skim Coat only – Cracking similar to conventional 3. Skim and Mesh – highly crack resistant
  186. 186. PWA 105 This is not EIFS … EIFS is defined as the (Finish cladding “and” the Weather Barrier)
  187. 187. PWA 105 Inexpensive cement basecoat - no control joints required – drift joints will be required Brown coat need not be hard floated encapsulate the foam for fire rating
  188. 188. Installs like traditional cement plaster
  189. 189. THE FOAM IN THESE ASSEMBLIES DOES NOT CANCEL THE FIRE RATING - PROVIDED …
  190. 190. Fire ratings  Flame Spread less than 25  Smoke Develop not more than 450  Thickness, less than 4 inches  Thermal barrier 1/2 inch of Gypsum
  191. 191. USING THE BROCHURE
  192. 192. How Much CI?  Step one: Climate Zone and Building Type – Have a PWA in Mind *Assume a Commercial Building in Climate zone 8
  193. 193. Step Two Our Target U factor is .062 or less ( assume R-19 Cavity)
  194. 194. Assume using PWA 104- we need R 7.0 assume (XPS) we need - Minimum 1.5 density @ 1.5”= R 7.5
  195. 195.  With cavity Insulation @ R - 19  & CI @ R 7.5  We Exceed the assembly U-Factor .062
  196. 196. Can’t afford a LAMINA ? Another look - Our target is a U factor of .062 or better Space framing @ 24 oc, add two inches foam (XPS) for a U-Factor of ?
  197. 197. 24 inch framing – saves money to offset the cost of adding a lamina A factor of .048 , possible credits elsewhere? Highly Crack Resistant
  198. 198. TECHNICAL SERVICES INFORMATION BUREAU WWW.TSIB.ORG Updates Details
  199. 199.  The WCWCI will hold seminars for Architects, Designers, Inspectors, Building Departments and Contractors The use of the systems are recommended to be installed by contractors who have completed the Western Conference of Wall and Ceiling Institutes educational seminar on “ Insulated Cement Plaster Systems”
  200. 200. THE END

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