Exterior Portland Cement Plaster Assemblies

TECHNICAL SERVICES INFORMATION BUREAU

Exterior Plaster Wall and Ceilings, Fire-Resistive & Drywall Assemblies:

Presented by the Technical Services Information

Bureau . . .

Darin CoatsBryan Stanley

Michael M. Logue

WESTERN WALL & CEILING CONTRACTORS ASSOCIATION


•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

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.

The original state association board members

1929 – 1988 …

Materials suppliers and manufacturers have long been an integral part of the Association

Back then plaster was applied over strips of wood called “wood lath”

Advancements in manufacturing brought new materials for lathing

Early metal lath provided better keying for the plaster scratch coat

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

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

Dick was instrumental in the development of the Data Guide and Reference Spec’s, and the original stucco textures and finishes brochure …

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.

The advent of the tract home in the 50’s put many Southern California plastering contractors on the map.

Past PresidentsGeo. M. Raymond C. B. Scott

Commercial and Residential markets continued to grow into the 1960’s and plaster was there to meet

the growing demands of designers

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

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”

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

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

Trade Promotion

2002 Construction Specifications Institute Annual Trade Show –Las Vegas, NV

Education

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

Third Party Field Inspections

100_2754.mov

Code Development

California Building Standards Commission

International Code Council

ASTM

ANSI

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

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

PORTLAND CEMENT PLASTER

Plaster is an ancient material, durable, inexpensive and versatile material...

HISTORIC PLASTER OVER MASONRY –OLD MILL - SAN MARINO, CA

HISTORIC PLASTER OVER MASONRY –OLD MILL - SAN MARINO, CA

SIMULATION OF AFRICAN NATIVE MUD PLASTERING – SAN DIEGO WILD ANIMAL PARK

SIMULATED STONE CASTLE – MODIFIED PLASTER SYSTEM – LEGOLAND

SIMULATED STONE FIREPLACE – MODIFIED PLASTER SYSTEM – LEGOLAND

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

MASONRY

Cast-in-Place Concrete / CMU

Cast-in-P lace Concrete

Cured 28 days – ACI 308R Clean ¼ in 10’

Cast-in-P lace Concret

Apply lath and 3 coat when matching framed and lathed walls

If Direct Applied, apply bonder evenly

Document Point / Patch by others

Cast-in-Place Concrete

Sodium Silicate bond breaker will dissipate and can be direct applied with plaster.Petroleum based, oil / paraffin etc. cannot be direct applied over.

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

MEDIUM DENSITY OVERLAYFORMS TOO SMOOTH FOR PLASTER

Cast-in-place Concrete – DIRECT APPLY

Concrete Masonry Units Yorba Linda High School – Perlite Plastering 2009

CMU

Joints Cut Flush 90 % Loaded Fully Cured Clean ¼ in. Alignment

CONCRETE MASONRY UNITS – DIRECT APPLY

WOOD

Wood

Wood

•Locate CJ - Vertical backing

Wood

•Sill Plate Offset

Wood

•Plywood Gaped 1/8 in.

SPACER NAIL – NO 1/8” GAP

Wood

•2 Layers grade “D”

ROLL FORMED METAL

Roll Formed Steel

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’

Steel Framing Construction Basics

Member Nomenclature

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.

Standardization600 S 162 - 54

• Steel Members are Standardized Using a Universal Designation System

6” member depth

Stud or Joist with Lips

1-5/8” Flange (1.625”)

Min. base metal thickness in mils

(0.054” = 54 mils)

Member Depth: Measured on studs: outside flanges. Measured on tracks: inside flanges.

AT LEAST ONE CREATIVE MIND

EVEN LOOKED BEYOND

CONVENTIONIAL MATERIALS

FOR THEIR PLASTER

SUBSTRATE…

CHAIN LINK FENCE ! ! !…CHAIN LINK FENCE ! ! !

Good plaster starts w ith good lathing

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 wireControl Joints – 100 SF – Provide Backing

Plaster CeilingsSuspended Iron / Lath / Tie WireNo Rib LathNo Sheathing / WRBDEFS – a good substitute

SUSPENDED CEILINGS

SADDLE TIES

DON’T USE SHEATHING AND WEATHER-RESISTANT BARRIERS

PLASTER CEILINGS

EXTERIOR GYP. SHEATHING - METAL STUD FRAMING

WHY USE IT?

•PROVIDES BACKING AND UNIFORM FLATNESS

•ELIMINATES MOST VERTICAL LINES

•PROVIDES ATTACHMENT FOR BUILDING PAPER

•REQUIRED FOR RATED CONSTRUCTION

EXTERIOR SHEATHING - METAL STUD FRAMING

WHY USE IT?

•PROVIDES BACKING AND UNIFORM FLATNESS

A: ELIMINATES MOST VERTICAL LINES

WHY USE IT?EXTERIOR SHEATHING - METAL STUD FRAMING

A: MAKES DEEP COLORS MORE CONSISTENT

WHY USE IT?EXTERIOR SHEATHING - METAL STUD FRAMING

PROVIDES ATTACHMENT FOR BUILDING PAPER

EXTERIOR SHEATHINGWHY USE SHEATHING?

•PUTS GYPSUM IN THE PLASER SYSTEM FOR RATED SYSTEMS

WEATHER-RESISTING BARRIER

The IBC & CBC use the term “Weather-Resisting Barrier“in the definition of “Exterior Wall Covering “ (§1402)

A Weather-Resisting Barrier is comprised of one or more Water-Resistive Barriers WRB

The WRB’s work together to create a weather-resistant exterior wall envelope (§1403.2)

What does the WRB do?

In a plastered wall (a drainage system) the WRB is the primary means of waterproofing

BUILDING PAPERS

GRADE “B”

GRADE “D”

SYNTHETIC OR NON-PAPER

TYPES OF COMMONLY USED BUILDING PAPERS

Paperback Lath

GRADE “B”

WATER PENETRATION RESISTANCE -RATED AT 16 HOURS

U.V. SENSATIVE - TENDS TO SHRINK AND WRINKLE

NOT VAPOR PERMEABLEAND CANNOT BE USED WITH WOOD-BASED SHEATHING

GRADE “B”

GRADE “B”

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”

GRADE “D”

GRADE “D”

CLASSIFIED GRADE “D” SUPERIOR PRODUCT IN AREA OF

HIGH WINDS - RESISTS TEARING

FELTDo 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.

FLASHING AND SEALANTS

SEA

LA

NT

S/CA

UL

KIN

G &

BA

CKE

R

# 40 TWO-PIECE EXPANSION JOINT

XJ 15 ONE-PIECE CONTROL JOINT

#40 TWO PIECE VERTICAL JOINT

LATHING

ACCESSORIESControl Joint: XJ-15

LATHING

ACCESSORIESInside Corner Joint: No. 30

LATHING ACCESSORIES

No. 5 Drip Mould

LATHING ACCESSORIESCASING BEADS - PLASTER GROUNDS

Short Flange No. 66

Expanded Flange No. 66

LACK OF CASING BEAD: NO DEFINITIVE SEPARATION TO DISSIMILAR MATERIAL


LACK OF CASING BEAD: RESULTANT CRACKING


GOOD USE OF CASING BEAD



LATHING ACCESSORIESOUTSIDE CORNER REINFORCEMENT

Corner Bead

Corner Aid

CORNER AIDOUTSIDE CORNER REINFORCEMENT

CORNER BEADOUTSIDE CORNER REINFORCEMENT

LATHING ACCESSORIES

Foundation Weep Screed

PER ASTM C 1063 - 7.11.5

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.

PLASTER BASES – TYPES OF LATH

Expanded MetalASTM C847

WOVEN WIRE ASTM C1032

WELDED WIRE - NO PAPER ASTM C933

WELDED WIRE WITH PAPER – ASTM C933

Scratch & Brown

CementLimeSandWater

NEGATIVE characteristics of Portland Cement Based Plaster

•Non-Structural

•Brittle

•Good Compressive Strength

•Poor Tensile Strength

•Shrinks During Hydration

•Prone to Cracking

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

PORTLAND CEMENT “SCRATCH”


NOTCHED TROWEL


SCARAFIER/COMB

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

PORTLAND CEMENT “BROWN”

PORTLAND CEMENT “BROWN”

Moist cure fresh brown coat to achieve 48 hours of continuous cement hydration …

Allow brown to dry cure for an additional 5 days

Summary, Average basecoat application:Apply scratch day 1Moist cure days 2-3Apply brown day 4Moist cure days 5-6Dry cure days 7-11Total 11 days

FINISH OPTIONS

INTEGRALLY COLORED CEMENT & ACRYLIC– Float Finish– Dash Finish – Troweled Finish

FINISH OPTIONS

COMMERCIAL TEXTURES

RECOMMENDED CHOICES

Fine

Sand

Float

Med.

Sand

Float

Heavy

Sand

Float

Light

Dash

Med.

Dash

Heavy

Dash

Tunnel

Dash

K.D.

Dash

FINISH OPTIONS

COMMERCIAL TEXTURES

ACCENT TEXTURES

MARBLE-

CRETE

COMBED SCRAPED

FINISH OPTIONS

RESIDENTIAL TEXTURES

Light Lace Heavy Lace

SPANISH ARIZONA

ROCK-N-ROLL FRIEZE

FINISH OPTIONS

THEME FINISHES

SIMULATED

TIMBER

SIMULATED

BRICK

SIMULATED

TRAVERTINE

FINISH OPTIONS

COMMERCIAL/RESIDENTIAL TEXTURES

POOR CHOICES

CAT

FACES

CAT FACES IN CRITICAL LIGHT

SANTA BARBARA STD. SMOOTH

HIGHLY LIKELY TO CRACK EXCESSIVELY

100% ACRYLIC FINISH•UNLIMITED COLORS•MAR & WEATHER RESISTANT

ACRYLIC FINISH

DESIGNING W/ FOAM“PLANT-ON” SHAPES

DESIGNING W/ FOAM“PLANT-ON” SHAPES

RECOMMEDED USE OF FOAM …

Off the Ground &Away from “Traffic

…POOR USE OF FOAM

At Ground Level

Refers to deposits of soluble compounds (salts) carried by water onto the surface of porous masonry or hydraulic cementitious materials.

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.

Efflorescence

Efflorescence

Efflorescence is not just limited to plaster …

Efflorescence

.. it can appear on any porous, hydraulic, cementitious material …

Plaster is the most difficult surface to remove efflorescence from

Efflorescence

It doesn’t always have to be white; it is often green, brown, or even black

Efflorescence

EFFLORESCENCE

Efflorescence can also flow unto the surface of non porous materials. It is often caused by precast elements with a horizontal top.

Efflorescenceat cracks can give an indication of the amount of water flow reaching the drainage plane

EFFLORESCENCE

Left untreated, it can accumulate into a quite a large amount of material

In nature, where time is measured in millions of years, efflorescence takes on a life form of its own …

Efflorescence

EFFLORESCENCE

Efflorescence

Three (3) Conditions must exist simultaneously for efflorescence to develop:1. Soluble salts must be present2. Water must contact the salts to form a solution3. The salt solution must have a path to migrate to a surface where the water can evaporate (precipitate out).

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 …

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.

Efflorescence

HOW DO I GET THIS STUFF CLEANED UP?

Efflorescence

www.tsib.org

Arizona

California

Nevada

Oregon

Washington

Plastering Information BureauSan Francisco –San Mateo

NortherN CaliforNia lath aNd Plaster Bureau

INTRODUCES

The following will change the

way exterior walls are built

Energy Codes

JAN 1, 2010

• ONE YEAR DELAY

•CA ENERGY ONLINE

•ASHRAE 90.1

Thermal Shorts

Correction Factor, Effective RE

ASHRAE Correction Factor 90.1 --- Effective R-value = R-value x Correction FactorThe 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.

California has 16 zones

No relation to ASHRAE Zones

Website in the Brochure

GOAL: Energy efficiency of 30% in the 2010 compared to the 2004 standard.

net-zero energy buildings by 2030.

Rigid Foam - Why?

ASHRAE and the energy

codes called and they

want it back!

REMEMBER THE “R” VALUE LOST DUE TO THERMAL SHORTS?

Cladding Neutral

The OBVIOUS CHOICE IS EIFS•CODE RECOGNIZED

•PROVEN

•READILY AVAILABLE

PROBLEM IS…MANY OWNERS

WONT USE EIFS – WE NEED

CODE COMPLIANT - 3-COAT

CEMENT IN OUR MARKETS

HERE’S WHAT WE HAVE:

PWA 104Cement 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”

General Design Recommendations ( All Stucco)

L/360 or stiffer

Vapor Permeable WRB

Plaster Mixes , ASTM C-926

16 inch OC framing - best performance

Mesh & Base “Lamina”

1. No Lamina - likely to crack more

2. Skim Coat only – Cracking similar to conventional

3. Skim and Mesh – highly crack resistant

OPTIONS

PWA 105

This is not EIFS …EIFS is defined as the (Finish cladding “and” the Weather Barrier)

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

PWA 105

Installs like traditional cement plaster

THE FOAM IN THESE

ASSEMBLIES DOES

NOT CANCEL THE FIRE

RATING - PROVIDED

…

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

USING THE

BROCHURE

How Much CI?

Step one: Climate Zone and Building Type – Have a PWA in Mind

*Assume a Commercial Building in Climate zone 8

Step Two Our Target U factor is .062 or less ( assume R-19 Cavity)

Assume using PWA 104- we need R 7.0

assume (XPS) we need - Minimum 1.5 density

@ 1.5”= R 7.5

With cavity Insulation @ R -19

& CI @ R 7.5 We Exceed the

assembly U-Factor .062

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 ?

Highly Crack Resistant

24 inch framing – saves money to offset the cost of adding a lamina

A factor of .048 , possible credits elsewhere?


WWW.TSIB.ORG

Updates Details

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”

The WCWCI will hold seminars for Architects, Designers, Inspectors, Building Departments and Contractors

THE END

Date post:	13-Sep-2014
Category:	Design
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