Astm stp 1585 2016

What newproblems have emerged e.g., additional code-mandated restrictions andconcerns with combustible foam plastics as part of exterior wall assemblies?What additional benefits of EIFS h

Selected Technical Papers

Exterior Insulation and Finish Systems (EIFS): Performance, Progress and

Selected technical PaPerS

StP1585

Editors: Peter E Nelson, Bill Egan

Exterior Insulation and Finish

Systems (EIFS): Performance, Progress, and Innovation

ASTM Stock #STP1585

DOI: 10.1520/STP1585-EB

ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959 Printed in the U.S.A.

Names: Symposium on Exterior Insulation and Finish Systems: Performance,

Progress and Innovation (2014 : New Orleans, La.), creator | Nelson,

Peter E., 1953- editor | Egan, Bill (Civil engineer), editor | ASTM

Committee E-6 on Performance of Buildings Subcommittee E06.58 on Exterior

Insulation and Finish Systems

Title: Exterior insulation and fnish systems (EIFS) : performance, progress,

and innovation / editors, Peter E Nelson, Bill Egan

Description: West Conshohocken, PA : ASTM International, [2016] | Papers

presented at a symposium held October 5-6, 2014, in New Orleans,

Louisiana, USA The symposium was sponsored by ASTM International E06 on

Performance of Buildings and Subcommittee E06.58 on Exterior Insulation

and Finish Systems | Includes bibliographical references and index

Identifers: LCCN 2016007700 (print) | LCCN 2016007854 (ebook) | ISBN

9780803176157 | ISBN 9780803176164 (eBook) | ISBN 9780803176164 ()

Subjects: LCSH: Exterior insulation and fnish systems—Congresses |

Exterior walls—Thermal properties—Congresses

Classifcation: LCC TH2238.7 S96 2014 (print) | LCC TH2238.7 (ebook) | DDC

693.8/32—dc23

LC record available at http://lccn.loc.gov/2016007700

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When citing papers from this publication, the appropriate citation includes the paper authors, “paper title,” STP title, STP number, book editor(s), ASTM International, West Conshohocken, PA, year, page range, paper DOI listed in the footnote of the paper A citation is provided on page one of each paper Printed in Mayfeld, PA

March, 2016

THIS COMPILATION OF Selected Technical Papers, STP1585, Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation, contains peer- reviewed papers that were presented at a symposium held October 5–6, 2014, in New Orleans, Louisiana, USA Te symposium was sponsored by ASTM Interna-tional E06 on Performance of Buildings and Subcommittee E06.58 on Exterior In-sulation and Finish Systems.

Symposium Chairpersons and STP Editors:

Peter E NelsonSimpson Gumpertz & Heger Waltham, MA, USA

Bill EganBASF Corporation Jacksonville, FL, USA

Foreword

Exterior Insulation and Finish Systems—Then and Now 1 Peter E Nelson

Code Acceptance of Exterior Insulation and Finish Systems and Exterior Insulation

Andre Desjarlais and David Johnston

Exterior Continuous Insulation and the Positive Impact on Building Envelope

Performance—Achieving New Energy Code Wall Insulation Metrics 67 Robert W Dazel

Beyond the Misconceptions, EIFS Can No Longer Go Unnoticed 80 Scott Robinson

Successful Strategies for EIFS Over-Cladding 88

A Judson Taylor

Design and Construction Considerations for EIFS and Exterior Wall Claddings

That Incorporate Continuous Insulation 113 Eric S Auman and Bill Egan

Exterior Insulation and Finish System Code Requirements and Fire Performance 130 Jesse J Beitel

Contents

Jefrey J Sobczak and James T Connaughton

Energy Savings from an EIFS Retroft of a Single-Family Residence 171 Peter B Harrison

A Review of Cladding Drainage Testing, Standards and Codes 183 Theresa A Weston and Kimdolyn Boone

A Case Study of Construction Challenges and Solutions: Installation of Exterior

Insulation and Finish System (EIFS) to an Existing Residential Structure 197 Terry L Viness

Use of Glass Mat Gypsum Sheathing as a Substrate for Exterior Insulation

Brian G Randall, Warren Barber, and Thad Goodman

Mark J Newton and Eric Smith

High-Efciency Exterior Insulation and Finish Systems: R-30 Walls in Three-Inch

Thickness—Modeling, Performance Testing, and Installation 248 Steve Altum, Lawrence Carbary, Aaron Seitz, Bill Preston, Roland Serino, and

Andrew Dunlap

Applicability of Fluid-Applied Air and Water-Resistive Barriers in Exterior

Insulation and Finish Systems for Use in Other Cladding Systems 265 Katherine S Wissink, Laura K Bashaw, and Peter E Nelson

Tis was the third ASTM symposium that specifcally pertained to Exterior sulation and Finish Systems (EIFS) Te frst ASTM EIFS symposium (1992, Wash-ington, DC) concentrated on development, use, and performance of EIFS, while the second ASTM EIFS symposium (1995, Denver, CO) focused on materials, proper-ties, and performance

In-Tis symposium reviewed many of the changes that have occurred in or impacted EIFS over the past two decades Topics discussed included progress with develop-ment of industry standards, tests, system performance, building codes, water resis-tive barriers, energy, products, and applications

Overview

Peter E Nelson1

Exterior Insulation and Finish

Systems—Then and Now

Citation

Nelson, P E., “Exterior Insulation and Finish Systems—Then and Now,” Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation, ASTM STP1585, P E Nelson and B Egan, Eds., ASTM International, West Conshohocken, PA, 2016, pp 1–7, doi:10.1520/ STP158520140111 2

ABSTRACT

This paper reviews some of the pressing issues and challenges presented inpapers from the first two ASTM exterior insulation and finish systems (EIFS)symposiums (ASTM STP1187—September 1992 and ASTM STP1269—March 1995)and compares them to EIFS today What has changed, and what has not, overthe last two decades? What pressing problems from 20 years ago have beenaddressed (e.g., absence of many options for drainable systems)? What newproblems have emerged (e.g., additional code-mandated restrictions andconcerns with combustible foam plastics as part of exterior wall assemblies)?What additional benefits of EIFS have emerged or been more fully appreciated inrecent years (e.g., code-mandated emphasis on continuous exterior insulation)?Keywords

exterior insulation and finish systems (EIFS), barrier EIFS, drainage EIFS

Introduction

This chapter reviews some of the issues and challenges presented in the first twoASTM exterior insulation and finish systems (EIFS) symposiums (ASTM STP1187,held in Washington, DC, September 1992, and ASTM STP1269, held in Denver,

CO, March 1995) and summarizes a few of the many topics the symposia authors

Manuscript received September 23, 2014; accepted for publication August 21, 2015.

1 Simpson Gumpertz& Heger Inc., 41 Seyon St., Waltham, MA 02453

2 ASTM Symposium on Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation

on October 5–6, 2014 in New Orleans.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1585, 2016 / available online at www astm org / doi: 10 1520/STP158520140111

wrote about It is important to note that these symposia were presented at a timewhen essentially all EIFS were the surface-sealed (or barrier) types that were applieddirectly to substrates without a backup water-resistive barrier and few, if any,flashings.

Since the 1995 symposium, the industry has learned many lessons that includeusingmore flashings to improve the weather resistance of EIFS and the adjoiningcomponents of the buildingenclosure, relyingless on surface seals and more onwater-resistive barriers, eliminatingpaper-faced gypsum sheathingfrom exteriorwalls, and installingmore expansion and control joints Due to energy demandsand code requirements, we have also seen continuous insulation becomingacommon requirement in exterior walls

Lessons Learned at the 1992 Symposium

In 1992, Mark Williams and Richard Lampo were the editors of ASTM STP1187[1] Williams provided an introduction highlighting the history and development

of EIFS, explainingthat EIFS were imported from Europe in the late 1960s andthat their use had been steadily increasingas of 1992 Twenty-eight papers coveredperformance-related topics, fire resistance, water vapor transmission, impact resist-ance, buildingcodes, maintenance and retrofit applications, sealant joints, andinnovations and current developments

Tamburrini [2] noted that an EIFS typically is designed as a barrier wall thathas “major code compliance.” The EIFS design concept was based on improvingenergy efficiency in Europe after World War II Early studies showed that using2–4 in of insulation applied to walls externally was 30 % more energy efficient than

a similar thickness of insulation used on the inboard side of walls Hence, this earlyversion of continuous insulation was identified as improvingenergy efficiencywhen applied to the exterior side of a wall

The majority of EIFS were defined as Class PB (polymer based) Class PB EIFStypically use an adhered layer of expanded polystyrene (EPS) insulation coveredwith a thin glass fiber reinforcing mat embedded with a polymer base and finishcoatings, or “lamina.” Less commonly used EIFS, defined as Class PM (polymermodified), have a basic structure usinga stiffer insulation such as extruded poly-styrene (XPS), are mechanically fastened, and have a thicker (as compared to ClassPB) polymer-modified, Portland cement-based, glass fiber-reinforced lamina Class

PM EIFS required placement of control joints with a layout similar to that requiredfor Portland cement plaster stucco

Fire ratings and flammability testing were an important consideration in theearly 1990s The EIFS Industry Members Association (EIMA) sponsored a largeresearch project to study this

In “EIFS Resistance to Moisture: Face Sealed Barrier Performance” [3],Williams and Williams (1995) evaluated the water resistance of PB EIFS laminas.The EIMA Guideline Specification for Class PB states that the system must resist

water infiltration at an applied air pressure difference of 2.86 lb/ft2 when tested

in accordance with ASTME331-86, Standard Test Method for Water Penetration ofExterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static AirPressure Difference,which uses a water application rate of 5 gal/sf/h At that time,EIMA also considered increasing the test pressure to 6.24 lb/ft2

Williams and Williams also discuss a water test conducted in accordance withASTM E331-86 at a much higher test pressure of 26 lb/ft2 with 60 gal/ft2/h waterspray in accordance with a federal requirement These water tests showed thatleakage occurred through the Class PB lamina where it was thinner than the manu-facturer’s recommended minimums (typically about 3/32 in.) Tests concluded thatthe thicker the lamina,the greater the water resistance During these tests leakagewas defined as water wetting the inside surface of the lamina—not the inside surface

of the insulation or the substrate on which the EIFS was mounted

Kudder and Lies (1995) reported on the “Durability and Serviceability ofPolymer Based EIFS” [4] Based on evaluating many EIFS applications,they notedthat paper-faced gypsum sheathing is the most common substrate for barrier EIFS.They warned that the ribbon and dab method of EIFS attachment can lead to rapidand premature failures Today,the ribbon and dab method of adhesive application

is seldom used because the insulation is adhered with adhesive applied in a verticalnotch trowel fashion

Kudder and Lies also reported on poor-quality EPS insulation that can degradeEIFS performance,leading to lamina failure and water leakage The EPS insulationneeds to be adequately aged before cutting board stock in order to have good beadfusion,characterized as a minimum of 50 % of the beads breaking when the board

is fractured Poor bead fusion can be linked to random cracking of the lamina awayfrom board joints Some cracking failures of the lamina are linked to defectivecoatings on the reinforcing mesh,where the mesh was not properly treated to resistalkali deterioration caused by the cement content of the base coat

Sealants are an important component in the overall performance of an EIFS,although many EIFS manufacturers do not supply the sealants Widespread cohe-sive failures of EIFS finish coats onto which sealant was bonded led the industry toprohibit extending the finish coat into the sealant joints Sealant should be applieddirectly onto the base coat and not onto the finish coat Some sealant manufacturersalso require the base coat to be primed Use of open cell backer rods,which absorband hold water against the back of the sealant joint,leading to premature jointfailure,gave way to nonabsorptive,closed cell backer rods

Problems with application of barrier EIFS adhered to substrates such as faced gypsum,which is prone to rapid deterioration when exposed to moisture,became a widely recognized failure mode Leakage through barrier EIFS attacks theunprotected sheathing,delaminating the paper facer and softening the gypsumcore,causing the EIFS to debond and fail Sometimes the failure mechanism is theresult of a screw pulling through the softened gypsum More durable substrates—such as cement board sheathing and masonry—are not damaged by the leakage

paper-NELSON, DOI 10.1520/STP158520140111 3

and moisture to the same degree as paper-faced gypsum sheathing As a result, newgypsum facers, such as glass mat (as specified by ASTMC1177-13, Standard Speci-fication for Glass Mat Gypsum Substrate for Use as Sheathing), have been developed

to improve the performance and durability of gypsum sheathing

Expansion or control joints in the EIFS are now recommended at locationswhere there are expansion joints in the substrate, changes in geometry, interfaceswith other fac¸ade systems, and at floor lines of wood-framed buildings There was anoticeable absence of recommendations for the maximum spacing of control joints

in 1993

Aesthetic reveals (noted as “rustications” in the 1990s) are not designed to tion as control joints, but these reveals have been found to develop cracks becausethey behave as control joints The standard recommendation for aesthetic revealsincludes a minimum thickness of 3/4 in of EPS behind the joint Another well-known cause for cracking is aligning the EPS board joints with the corners of thewindow openings, the joints in the gypsum sheathing, and with the aesthetic reveals

func-Lessons Learned at the 1995 Symposium

The second EIFS symposium was held in 1995 and was chaired by Peter Nelsonand Dick Kroll ASTM STP1269 [5] had 14 papers concentrating on materials,properties, and performance of EIFS The need for improved water resistance anddurability required improvements in the EIFS flashings and details, including theuse of a drainage plane with EIFS

Zwayer reports in “EIFS: When It Works, When It Does Not” [6] that EIFS

“perform well when they are properly designed and constructed and have problemswhen they were not.” He reviewed a few well-designed and well-installed projectsthat included EIFS application over steel studs and EIFS application over masonry.Zwayer’s paper also notes a number of common problems, including:

• Gaps for sealant joints that are not wide enough for the sealant—a problemfrequently found at windows

• Backwrapped mesh not fully embedded in the base coat, leaving a poroussurface and making watertight installation of sealant difficult

• Installation of EPS boards with gaps that become filled with base coat, leading

to cracks in the lamina and—ultimately—water entry

• Structural movement of the steel stud backup causing cracks in the EIFS.Examples include construction sequencing and improperly designed studsallowing large movement and deflections in the steel studs, leading to EIFScracking

Zwayer concludes that some EIFS problems have been avoided on many ects and can be avoided on all EIFS projects by proper attention to design, detailing,and installation by the architect, manufacturers, and applicators It was noted thatEIMA and ASTM Task Group E06.58—Subcommittee on EIFS would also help

proj-by disseminating proper information about the design and installation of EIFS toimprove the quality of installations

Remmele’s paper, “EIFS Resistance to Water Penetration and Evaluation inAccordance with EIMA Test Method 101.02” [7] was based on water testing ofbarrier EIFS using ASTME331 That EIMA test standard defines water leakage as

“penetration of water into the plane of the innermost face of the test specimen.”Strictly speaking, for barrier EIFS, one could interpret this as being the inside plane

of the EPS insulation because the insulation is an integral component of EIFS ever, EIMA wanted to evaluate the leakage through the lamina without analyzingthe storage capacity or management of the leakage water by the EPS To evaluatethe water leakage through the lamina, tracer dyes, perforated sheathing substrates,and disassembly after the test were used to gain better access to the back of thelamina (with the foam still being used to support the lamina) Differential testpressures were 6.24 lb/ft2 Test results showed no water penetration through thelamina The test lab noted that the “degree of water penetration appeared to go nofurther than the interface of the reinforced base coat and finish coat” [7]

How-Nelson and Waltz’s paper, “EIFS—Surface-Sealed Wall Systems that NeedFlashings” [8] concentrated on the surface-sealed barrier wall and improving itsperformance by designing proper flashings Surface-sealed EIFS over water-sensitive components such as paper-faced gypsum sheathing do not protect thesheathing or building because there is no internal water management Drainageplane wall systems introduced water-resistive barriers and drainage behind theinsulation The paper describes many types of wall flashing details, such aswindow sill, jamb, and head flashings; panned up flashing end dams for win-dows and other wall penetrations; flashing materials; workmanship; sequencing;properties of flashing materials; drip edges; splices; flashing attachment; anddual sealant joints that protect commonly identified vulnerabilities in barrierEIFS Design development of the flashings at intersections with other systems isnecessary to improve the weatherproofing performance These flashings should

be further refined and evaluated by incorporating them into mock-ups and ing prior to installation

test-Currently, EIFS manufacturers have developed a number of details for flashingwindows and doors for barrier EIFS and EIFS with drainage ASTM has publishedASTME2112-07, Standard Practice for Installation ofExterior Windows, Doors andSkylights, which offers a substantial amount of information on how to properlyflash windows and doors

The Legacy of Surface-Sealed EIFS

Surface-sealed or barrier EIFS are still being used in some areas today, although wesee fewer of these systems In the 1990s, barrier EIFS were identified as the source

of significant leakage in buildings A few states, including North Carolina, Georgia,and Oregon, banned barrier EIFS from the late 1990s through the early 2000s

A North Carolina class action lawsuit and the damaged reputation of EIFS can belinked to the large number of EIFS projects that had water intrusion problems

NELSON, DOI 10.1520/STP158520140111 5

Many of these installations were residential projects that lacked sealant and ings at windows, wall penetrations, and at EIFS terminations A number of localitiesalso banned barrier EIFS, which were then replaced by EIFS with drainage, whichare more durable wall systems.

flash-The International Residential Code restricts barrier EIFS to masonry substrates,and the International Building Code does not allow barrier EIFS to be used inwood- or steel-framed construction However, EIFS with drainage are permittedeverywhere—in Type V, Group R1, R2, R3, or R4 construction

Another concern is that moisture damage of concealed components is notreadily detected by visual observation alone Continuous insulation (CI) can storemoisture, but it does not readily show the extent of any concealed damage and canobscure nondestructive testing methods such as infrared thermography Destructivesampling is the best method for determining the condition of the sheathing and theextent of any concealed damage Another less intrusive inspection method involvesusing moisture meters Moisture meters with long pins are inserted through smallholes in the EIFS lamina and foam (EPS or XPS) to measure the moisture content ofthe backup sheathing Poking holes through the EIFS for the moisture meter also hassome negative appearance and functionality effects How do you patch the holes inthe water-resistive barrier covering the sheathing and the EIFS lamina? It is best totake interior and or exterior destructive samples along with the moisture measure-ments to confirm the conditions of the concealed components This issue is notunique to EIFS but is common to any exterior wall system with insulation outboard

of the water-resistive barrier CI covers the materials that may be sensitive to term moisture deterioration, making it harder to visually assess their condition with-out intrusive sampling This enforces the need for evaluation during installationbecause once the cladding is installed you cannot see the concealed construction.Barrier EIFS problems in the 1990s resulted in widespread negative publicityfor the EIFS industry throughout the design and construction community.Twenty years later, the lingering stigma remains—even though most modernEIFS with drainage have been performing successfully for more than 15 years.Current, state-of-the-art EIFS provide what essentially remains of the barrier EIFSapplied over a water-resistive barrier and moisture-tolerant sheathing andcombined with effective flashing details and a drainage plane to manage waterinfiltration and prevent moisture damage to the structure

long-References

[1] Williams, M F and Lampo, R G., Eds., Development, Use, and Performance of Exterior Insulation and Finish Systems (EIFS), ASTMSTP1187, ASTM International, West Consho- hocken, PA, 1995.

[2] Tamburrini, V., “The History and Development of EIFS—From the Original Concept to Present Day Activities,” Development, Use, and Performance of Exterior Insulation and

Finish Systems (EIFS), ASTM STP1187, M F Williams and R G Lampo, Eds., ASTM national, West Conshohocken, PA, 1995, pp 3–12.

Inter-[3] Williams, M F., and Williams, B L., “EIFS Resistance to Moisture: Face Sealed Barrier Performance,” Development, Use, and Performance of Exterior Insulation and Finish Systems (EIFS), ASTM STP1187, M F Williams and R G Lampo, Eds., ASTM International, West Conshohocken, PA, 1995, pp 175–191.

[4] Kudder, R J., and Lies, K M., “Durability and Serviceability of Polymer Based EIFS,” Development, Use, and Performance of Exterior Insulation and Finish Systems (EIFS), ASTM STP1187, M F Williams and R G Lampo, Eds., ASTM International, West Consho- hocken, PA, 1 995, pp 74–88.

[5] Nelson, P E and Kroll, R E., Eds., Exterior Insulation Finish Systems (EIFS), Materials, Properties, and Performance, ASTM STP1269, ASTM International, West Conshohocken,

NELSON, DOI 10.1520/STP158520140111 7

William M Preston1

Code Acceptance of Exterior

Insulation and Finish Systems and

Exterior Insulation and Finish

Systems with Drainage

Citation

Preston, W M., “Code Acceptance of Exterior Insulation and Finish Systems and Exterior Insulation and Finish Systems with Drainage,” Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation, ASTM STP1585, P E Nelson and B Egan, Eds., ASTM International, West Conshohocken, PA, 2016, pp 8–15, doi:10.1520/STP158520140105 2

ABSTRACT

Exterior insulation and finish systems (EIFS) have been installed in the UnitedStates for more than 40 years When first introduced, there were no standards inplace and the thought of securing expanded polystyrene on the exterior of anoncombustible wall was unheard of Fast forward to today: Not only havestandards been developed but exterior insulation and finish systems and exteriorinsulation and finish systems with drainage are included in both the InternationalBuilding Code (IBC) and the International Residential Code (IRC) This paper willpresent, in chronological order, howEIFS have become established in themarketplace through acceptance criteria, the development of standards, therigorous testing that goes along with those standards, and ultimately, in 2009,through the acceptance of EIFS and EIFS with drainage into the IBC and IRC.Keywords

exterior insulation and finish systems (EIFS), EIFS Industry Members Association (EIMA), International Code Council (ICC), International Building Code (IBC), International Residential Code (IRC), alternate materials, acceptance criteria, evaluation reports

Manuscript received September 12, 2014; accepted for publication June 23, 2015.

1 Dryvit Systems, Inc., One Energy Way, West Warwick, RI 02893

2 ASTM Symposium on Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation on October 5–6, 2014 in New Orleans.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1585, 2016 / available online at www astm org / doi: 10 1520/STP158520140105

Exterior insulation and finish systems (EIFS) were first introduced in the U.S ket in 1969 At the time of introduction, there were three regional model buildingcodes in place that covered the continental United States:

mar-• The Building Officials and Code Administrators International (BOCA) trated on areas north ofthe Mason-Dixon Line and east ofthe Mississippi River

concen-• The Southern Building Code Congress International (SBCCI) concentrated onareas south of the Mason-Dixon Line and east of the Mississippi River

• The International Conference of Building Officials (ICBO) concentrated on allareas west of the Mississippi River

All three building codes were silent on the acceptance of EIFS Conversationswith building officials at the local level indicated that the industry would have toprove that the application of foam plastic on the exterior wall would not affect theminimum requirements of the code, which states:

The purpose of this code is to establish the minimum requirements tosafeguard the public health, safety, and general welfare through structuralstrength, means of egress facilities, stability, sanitation, adequate light andventilation, energy, conservation, and safety to life and property from fire andother hazards attributed to the built environment and to provide safety to firefighters and emergency responders during emergency operations [1]

The language noted here has been reproduced from the 2012 IBC; however, theintent of the codes in 1969 (when EIFS were first introduced to this country) wasthe same The industry hired consultants to work in conjunction with the variouscodes to obtain approval of EIFS Because EIFS were not a part of the existing code,they were classified as alternate materials and equipment as defined by code Alter-nate materials and equipment are defined as follows:

The provisions of this code are not intended to prevent the use of any material

or method of construction not specifically prescribed by this code, providedany such alternative has been approved An alternative material or method ofconstruction shall be approved when the code official finds that the proposeddesign is satisfactory and complies with the intent of the provisions of thiscode, and that the material, method, or work offered is, for the purposeintended, at least the equivalent of that prescribed in this code in quality,strength, effectiveness, fire-resistance, durability, and safety [2]

Although regional code development had been effective and responsive to theregulatory needs of the local jurisdictions, by the early 1990 it had become evidentthat the United States needed a single set of national model building codes Thethree model code groups, as noted earlier, decided to combine their efforts and, in

1994, formed the International Code Council (ICC) to develop codes that would

PRESTON, DOI 10.1520/STP158520140105 9

have no regional limitations After three years of research and development, thefirst edition of the International Building Code (IBC) was published for public com-ment By 2000, the ICC completed the International Codes series (IBC, IRC, IECC,etc.) and ceased development of the legacy codes.

Evaluation Process

Because EIFS were considered an alternate material prior to 2009, it was necessary tohave the systems evaluated by an independent service to ensure that the systems metthe intent ofthe building code As noted earlier, there were three regional model build-ing codes; therefore, separate evaluation reports were normally issued for each code

An exception to that was if one opted to obtain a single evaluation report that wouldqualify the system for all three codes It should be noted that, prior to 1993, each evalu-ation service (BOCA, ICBO, and SBCCI) produced evaluation reports without an ac-ceptance criteria Prior to the development of acceptance criteria, EIFS manufacturerswould submit testing to the evaluation service; it was then left to the discretion of thereviewer as to whether the system met the intent ofthe code It was not uncommon for

an evaluation report to take upwards ofa year for publication

In 1993, AC24, Acceptance Criteria for Exterior Insulation and Finish Systems[3], was the first criteria published for the EIFS industry Acceptance criteria weredeveloped by the International Conference of Building Officials Evaluation Service(ICBO-ES) to provide a set of guidelines for manufacturers of construction products.(Currently, the ICC-ES has more than 250 acceptance criteria for various products.)

It took 24 years for a formal set of guidelines to be published by the ICBO-ES

AC 24 was considered the “bible” for EIFS manufacturers to follow for ing their systems in accordance with the requirements of the code AC 24 was origi-nally based on the Uniform Building Code and was for face-sealed (“barrier”)systems As time went on, and all three codes merged into the ICC, the acceptancecriteria were updated to mirror the requirements of the IBC In 1997 the require-ments for use of water-resistive barriers and a means for drainage were established.The introduction of these materials and systems required that the acceptance crite-ria be revised to reflect these new products The EIFS industry worked in conjunc-tion with the ICBO-ES/ICC-ES staff to develop requirements for both EIFS withdrainage and liquid-applied water-resistive barriers Originally, these requirementswere included in AC 24; however, the criteria became unmanageable and the needfor separate criteria was born The following criteria were developed through theEIFS industry and ICC-ES staff:

qualify-• AC 24, Acceptance Criteria for Exterior Insulation and Finish Systems (thecriteria include the requirements as noted in AC 219, AC 235, and AC 212); ithas been replaced by the following individual criteria

• AC 219, Acceptance Criteria for Exterior Insulation and Finish Systems [4]

• AC 235, Acceptance Criteria for EIFS Clad Drainage Wall Assemblies [5]

• AC 212, Acceptance Criteria for Resistive Coatings Used as Resistive Barriers over Exterior Sheathing [6]

Water-Having criteria was important for two reasons:

1 It kept all manufacturers on a level playing field by establishing a minimumcriteria

2 It was the basis for obtaining evaluation reports/research reports

Because the thrust of the EIFS industry was to get EIFS and EIFS with drainagepublished in the building code, it was essential to obtain consensus standards for alltesting associated with the systems, including acceptance criteria Unfortunately,EIFS Industry Members Association (EIMA) standards and acceptance criteria maynot be referenced in the building code

Testing for durability, structural, and fire were included in each of the tance criteria EIFS, as an exterior cladding system, requires that the system andassociated products are not affected by varying weather conditions such as freeze-thaw, weathering, impact, wind, water resistance, and so on The systems are in-stalled worldwide, thus creating the necessity of testing to a myriad of weatherexposures The durability testing referenced in the following tables represents theweather conditions to which the systems will be exposed

accep-Additionally, because foam plastic is the most common insulant (in the UnitedStates) used in an EIFS, it is imperative to qualify the system for fire performance inorder to install the system on walls classified as noncombustible The fire tests(NFPA 285 and NFPA 268) have been derived from research simulating actual fireconditions

The following tests (see Tables 1–6) are required in order to bring an EIFS orEIFS with drainage to market in the United States The tests listed are all includedwithin ASTME2568[7] with the exception of ASTME2273[8]

TABLE 1 System performance tests (EIFS and EIFS with drainage).

Test Test Method Criteria

Accelerated Weathering ASTM G153 a or G155 b , c No deleterious effects after 2000 h Freeze-Thaw ASTM E2485 d Method B No deleterious effects after

10 cycles Salt Spray Resistance ASTM B117 No deleterious effects after 300 h

Tensile Bond Adhesion ASTM E2134 e or C297 15 psi (103 kPa) minimum

Water Penetration ASTM E331 f No water penetration after 2 h at

6.24 psf (299 Pa) Water Resistance ASTM D2247 No deleterious effects after 14 days

a Formerly ASTM G23.

b Formerly ASTM G26.

c Results from ASTM G155 Cycle 1 and G153 Cycle 1 cannot be directly compared.

d Formerly EIMA Standard 101.01.

e Formerly EIMA Standard 101.03.

f Formerly EIMA Standard 101.02.

g Drainage efficiency only required for EIFS with drainage.

PRESTON, DOI 10.1520/STP158520140105 11

Not only was it necessary to convert EIMA standards to consensus standards(refer to footnotes of the aforementioned referenced tables) for submitting a codechange, it was also necessary to get approval from the ICC-ESto convert the accep-tance criteria that were specified for EIFS, EIFS with drainage, and water-resistive

Test Test Method Criteria

EPS Physical Properties ASTM C578 Meets Type I or manufacturer specification Polyisocyanurate Physical Properties ASTM C1289 Meets Type II,Class 2 or 3

Alkali Resistance of Reinforcing Mesh ASTM E2098 120 pli (21 dN/cm) retained tensile strength

TABLE 3 System fire performance tests for noncombustible construction.

Test Test Method Criteria

Fire Endurance ASTM E119 a Maintain fire resistance of known rated wall assembly

Full-Scale Test NFPA 285 b 1 Resistance to vertical spread of flame within the core of the

panel from one story to the next

2 Resistance to flame propagation over the exterior face of the system

3 Resistance to vertical spread of flame over the interior (room side) surface from one story to the next

4 Resistance to lateral spread of flame from the compartment of fire origin to adjacent spaces

b Formerly referred to as UBC 17-6, 26-4, and 26-9.

c Formerly referred to as BOCA 1406.2.1.

TABLE 4 Fire performance test.

Test MethodTest Criteria

Surface Burning ASTM E84 Insulation board and reinforced coating system shall each separately

have a flame spread of 25 or less and smoke developed of 450 or less.

TABLE 5 Structural performance tests.

Test Test Method Criteria

Wind Load ASTM E330 Report negative and positive wind load values.

barriers used beneath EIFS and EIFS with drainage Table 7 shows what theseacceptance criteria are now referred to as.

Having consensus standards allowed the EIFS industry to propose a code change

to both the 2009 International Building Code and the 2009 International ResidentialCode Following public hearings and a vote of the ICC membership, EIFS, EIFS withdrainage, and water-resistive barriers used beneath EIFS were all successfully added

to the 2009 code Obtaining code approval was a milestone for the EIFS industry

Why was it so important for EIFS to be accepted into the building code?Obtaining code approval legitimized the system that was being installed on exteriorwalls of both residential and commercial construction for 40 years Prior to beingincluded in the code, acceptance of the system was left to the discretion of the codeofficial Once EIFS and EIFS with drainage obtained code acceptance, each type

of system immediately became equivalent to other materials listed in the code.Although EIFS are listed in the building code, manufacturers continue to maintainthe evaluation reports for individual systems or products Because EIFS are no lon-ger considered an alternate material, as noted previously, it is our hope that once alljurisdictions adopt (at minimum) the 2009 code, these reports will no longer benecessary

Summary of code requirements for EIFS in the IBC:

• Chapter 2: Added definition for EIFS and EIFS with drainage

• Chapter 14:

• Added definition in Section 1402

• Added Section 1408 EIFS

TABLE 7 Acceptance criteria.

Title AC/Standard Consensus Standard

Acceptance Criteria for EIFS with

Drainage

AC 235 ASTM E2568 with the addition of ASTM E2273

Acceptance Criteria for

Water-Resistive Barrier Coatings Used

Beneath EIFS

Test Test Method Criteria

Impact Resistance ASTM E2486 a Standard: 25–49 in–lb (2.83–5.54J)

Medium: 50–89 in–lb (5.65–10.1J) High: 90–150 in–lb (10.2–17J) Ultra High: >150 in–lb (>17J)

a Formerly EIMA Standard 101.86.

PRESTON, DOI 10.1520/STP158520140105 13

• EIFS shall comply with ASTME2568

• Makes reference to structural frame, and substrate shall comply withChapter 16

• Makes reference for EIFS to comply with Section 1403

• Makes reference to special inspections in accordance with Chapter 17

• Makes reference to the requirements of Chapter 26 for foam plasticUnder the IBC, EIFS are now acceptable on all types of construction with theexception of framed walls of Type V, Group R1, R2, R3, or R4 (EIFS with drainage

is required on Type V, Group R1 through R4) construction provided all tests havebeen completed qualifying the system for use The important factor is to ensurethat the system being specified has been tested in its end-use configuration Thisincludes all the materials that are specified by the manufacturer A number ofproducts are available on the market today that may look equivalent, but onlythose products supplied by the manufacturers’ or their authorized distributors areacceptable Purchasing or combining different manufacturers’ materials are neitheracceptable nor considered code-compliant

Summary of code requirements for EIFS in the IRC:

• Chapter 2: Added definition for EIFS and EIFS with drainage

• Chapter 7:

• Added Section R703.9 EIFS/EIFS with drainage

• EIFS shall comply with ASTME2568

• EIFS and EIFS with drainage shall comply with ASTM E2568 and shallhave a minimum drainage efficiency of 90 % when tested in accordancewith ASTME2273

• Water-resistive barriers are required on framed walls with sheathing andshall comply with ASTME2570or R703.2 of the code

Under the IRC, EIFS shall be limited to applications over concrete or masonrywall assemblies (substrates) Under the IRC, EIFS with drainage shall be requiredover all wall assemblies with the exception of concrete and masonry EIFS withdrainage require a water-resistive barrier that shall be applied between the EIFS andthe wall sheathing Again, the EIFS or EIFS with drainage provided under the IRCshall be obtained from the EIFS manufacturer or its authorized distributors Pur-chasing or combining different manufacturers’ materials are neither acceptable norconsidered code-compliant

Inclusion in the code was a major milestone for the EIFS industry EIFS havebeen in the marketplace for 45 years in the United States, and they are currentlyinstalled on approximately 20 % of new opaque wall areas EIFS are the most testedwall assembly and are able to comply with all current structural, durability, andfire requirements Because the insulation is installed on the exterior of the wall(making it totally effective), it also meets the IECC requirements for continuousinsulation (ci) Now that EIFS and EIFS with drainage are in the code, they can betreated equally to other approved b uilding materials and can b e specified withconfidence

• Don Belles and Lavern Cary: Don and Lavern were consultants to the EIFSindustry who were instrumental in developing tests and standards to qualifythe use of EIFS for noncombustible construction Their countless hoursdefending EIFS in the code arena provided the foundation that was ultimatelyused to obtain code approval.

• Michael Beaton, vice president of ICC-ES, in 2008: Mike provided guidanceand support in the development of the code language that was submitted toboth the IBC and the IRC

References

[1] 2012 International Building Code, Section 101.3, Country Club Hills, IL.

[2] 2012 International Building Code, Section 104.11, Country Club Hills, IL.

[3] AC 24, Acceptance Criteria for Exterior Insulation and Finish Systems, International Code Council Evaluation Service (ICC-ES), Whittier, CA, July 2003.

[4] AC 219, Acceptance Criteria for Exterior Insulation and Finish Systems, International Code Council Evaluation Service (ICC-ES), Whittier, CA, November 2009.

[5] AC 235, Acceptance Criteria for EIFS Clad Drainage Wall Assemblies, International Code Council Evaluation Service (ICC-ES), Whittier, CA, November 2009.

[6] AC 212, Acceptance Criteria for Water-Resistive Coatings Used as Water-Resistive riers over Exterior Sheathing, International Code Council Evaluation Service (ICC-ES), Whittier, CA, November 2009.

Vol 4.12, ASTM International, West Conshohocken, PA, 2007, www.astm.org

Insulation and Finish System (EIFS) Clad Wall Assemblies, Vol 4.12, ASTM International, West Conshohocken, PA, 2007, www.astm.org

[9] ASTM E2570, Standard Test Methods for Evaluating Water-Resistive Barrier (WRB) Coatings Used Under Exterior Insulation and Finish Systems (EIFS) or EIFS with Drain- age, Vol 4.12, ASTM International, West Conshohocken, PA, 2007, www.astm.org

PRESTON, DOI 10.1520/STP158520140105 15

Michael Horst1

Compatibility and Integration

Details: The Keys to Providing

Durable EIFS-Clad Exterior Walls

Citation

Horst, M., “Compatibility and Integration Details: The Keys to Providing Durable EIFS-Clad Exterior Walls,” Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation, ASTM STP1585, P E Nelson and B Egan, Eds., ASTM International, West Conshohocken,

PA, 2016, pp 16–51, doi:10.1520/STP158520150004 2

ABSTRACT

Exterior insulation and finish systems (EIFS) can provide a durable, resistant covering for a variety of building types However, as with any claddingmaterial, considerations during design and workmanship during constructionare the primary factors in determining the success of an EIFS-clad building.Among the important factors to consider in the design of EIFS cladding is thatthe EIFS is only one component of the overall building enclosure system, whichincludes roofing, windows, sealants, possibly other cladding materials, and manyother elements During the design phase of a project, careful consideration must

water-be given to the compatibility of other enclosure components with the EIFS Inaddition, detailing of the interfaces between the EIFS and these components,typically referred to as integration details, is critical in achieving the expectedbuilding performance and durability of the exterior cladding assembly Duringthe construction phase, coordination of various trades, including the EIFSinstaller, is essential to ensuring successful installation of these integrationdetails Over the past 15 years, the author has had the opportunity to evaluate avariety of EIFS-clad buildings that exhibit successes and failures of theseintegration details More recently, the author has performed peer reviews fordesign architects and has provided consulting services to assist contractors withpotential compatibility issues and with developing integration details In this

Manuscript received January 9, 2015; accepted for publication August 18, 2015.

1 Wiss, Janney, Elstner Associates, Inc., 2915 Premier Pkwy., Suite 100, Duluth, GA 30097

2 ASTM Symposium on Exterior Insulation and Finish Systems (EIFS): Performance, Progress, and Innovation

on October 5–6, 2014 in New Orleans.

Copyright V 2016 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.

STP 1585, 2016 / available online at www astm org / doi: 10 1520/STP158520150004

paper, the author will discuss several common problematic interfaces betweenEIFS and adjacent construction Design principles and other considerations forimproving the function of the exterior building enclosure at these interfaces will

be explored Several case studies, including positive and negative examples ofdesign and construction details, will be used to illustrate concerns with theirintegration In addition, the paper will identify and discuss facets of several ofthe standards that have been developed by ASTM International (ASTM) to assistdesigners, consultants, and contractors in the development of integration detailsand the determination of their compatibility

dili-on the building, the adjacent materials were compatible with the EIFS, and thedetailing at the interface of the EIFS and adjacent building enclosure componentswas properly conceived and implemented

In order to achieve the desired durability, careful consideration must be given,during the design phase of a project, to the compatibility of the EIFS with adjacentbuilding components, building usage, and other elements of the environment.The designer should also provide details for the integration of EIFS with othercladding materials and for the integration of various building components withthe EIFS In addition, successful, durable EIFS installation requires the contractorand installer to coordinate with the various trades involved in the enclosure con-struction to ensure that these integration details are appropriately implemented.Several common compatibility issues and problematic interfaces between EIFSand adjacent construction are highlighted in this paper and demonstrated throughexamples In addition, design principles and other considerations for improvingthe durability of the exterior enclosure at these interfaces are discussed andillustrated through actual design details The role of ASTM standards in achievingdurable EIFS installation is also examined The paper concludes with brief casestudies of two EIFS-clad buildings that are about 30 years old

HORST, DOI 10.1520/STP158520150004 17

EIFS were introduced in the United States in 1969 [1] These early EIFS utilized

an impervious barrier to prevent water infiltration through the wall system TheseEIFS relied totally on the integrity of the base coat, adjoining sealants, and on theadjacent building enclosure components to prevent water leakage In the early tomid-1990s, EIFS with drainage were developed that used a water-resistive barrier(WRB), drainage plane, and flashings to collect any incidental water thatpenetrated the exterior face of the wall system, prevent it from entering thebuilding, and to drain it to the exterior EIFS have been installed on a wide variety

of buildings, ranging from single and multifamily residences to offices, hotels,and hospitals

Over the years, EIFS manufacturers have continued to develop more details toprovide guidance to designers and installers for a variety of interfaces and condi-tions In addition, industry groups, such as the EIFS Industry Manufacturer’s Asso-ciation (EIMA) and the Association of the Wall and Ceiling Industry (AWCI)among others, have prepared training materials and guidance documents for EIFSinstallers, designers, and inspectors ASTM has also developed standards to assistdesigners and contractors with design and installation of EIFS

Among the common themes in the manufacturer’s details, industry groupguidelines, and ASTM standards is that the responsibility for design of the inter-face conditions remains with the design professional and that proper installation

is the responsibility of the contractor and subcontractor However, even with allthe information available, inadequate design and installation still occur, resulting

in reduced durability of EIFS cladding and oftentimes damage and deterioration

to exterior wall components and interior finishes These continued failures, alongwith the examples of successful, durable EIFS-clad structures, were the impetusfor this paper

Functional and Environmental Compatibility

In order to promote durability, one of the decisions that should be made early in theplanning and design process of any building cladding system, including EIFS, iswhether the cladding is compatible with specific functional areas of the building andenvironmental conditions to which it will be exposed Common problem areas withEIFS-clad buildings include impact zones and horizontal or low-slope applications.IMPACT ZONES

Impact zones can occur at a variety of locations throughout a building The pated impacts at these locations could be considered to vary from light to heavy.Walkways along the sides of buildings and balconies—where the impacts are gener-ally limited to forces exerted by a person—are examples of relatively light-impactzones Moderate-impact zones include main entrances of buildings and other high-traffic locations, as well as areas where luggage carts or shopping carts could impact

antici-the EIFS The most severe type of impact areas are those where a vehicle or heavyload may impact the EIFS cladding, such as a loading dock Each of these areas hasdifferent concerns and should be treated accordingly.

LIGHT-IMPACT ZONES

EIFS cladding has frequently been successfully installed at locations subject to lightimpacts The primary method of achieving durability for these areas is the design andinstallation of a heavier reinforcing mesh As stated in ASTM C1397-13 [2] andASTME2511-09 [3], the location of the heavier mesh should be detailed on the pro-ject drawings and specifications Care must be taken during construction to ensurethat the heavy reinforcing mesh is installed at the locations required on the drawings.MODERATE-IMPACT ZONES

The use of high-impact mesh will also increase the durability of the EIFS in impact zones As discussed previously, these areas—which would include hotelbreezeways or entrances, shopping center entrances, emergency room entrances,and landscaped areas—are subject to frequent impact by carts, gurneys, hand-operated mowers, or similar equipment Installation of heavy reinforcing mesh inthese areas is typically successful in reducing or eliminating damage throughoutmost of the wall areas subject to moderate impacts However, right-angle outside-wall corners remain vulnerable to damage from these moderate impacts, asillustrated inFig 1 In addition, high-impact mesh does not protect the finish coat,

moderate-or the base coat covering the mesh, from abrasion that often occurs at these wallsurfaces

impacts.

HORST, DOI 10.1520/STP158520150004 19

In new projects, consideration should be given to designing obtuse exteriorcorners in lieu of right angles or to providing additional means of protection, such

as installing a more impact- and abrasion-resistant cladding material on the lowerportions of the wall to prevent damage to the EIFS In repair scenarios, installation

of a different cladding material in the likely impact areas, a protective covering, or

of a barrier is sometimes warranted.Fig 2 is an example where a steel angle wasadded to one corner, and impact damage remains visible on adjacent corner condi-tions that remain exposed to moderate-impact damage Similar guidance is provided

in ASTME2511-09 [3]

HEAVY-IMPACT ZONES

The installation of high-impact mesh is not likely to prevent damage to EIFS inareas subject to impact by forklifts, other vehicles, or by heavy loads, such as mayoccur at loading docks or in parking garages These forces will likely puncture thelamina of the EIFS even with the heavier mesh in place Abrasion damage alsofrequently occurs in areas of buildings subjected to heavy impacts In these areas,consideration should be given to installing a more impact-resistant claddingmaterial, such as masonry, or a barrier to prevent objects from impacting the EIFS

corner condition that remains exposed to moderate-impact damage.

Fig 3 is an example of bollards installed at a parking garage to prevent vehiclesfrom impacting the EIFS cladding.

HORIZONTAL SURFACES

EIFS installed on horizontal or low-slope surfaces are not durable These tions frequentlyoccur at the tops of exterior walls and at architectural trim ele-ments Erosion of the finish coat on a horizontal or low-sloped surface canoccur in a relativelyshort amount of time The base coat will also erode and de-grade, eventuallyexposing the reinforcing mesh and insulation This can lead

condi-to a varietyof failure scenarios, including detachment of the EIFS, deterioration

of the insulation (see Fig 4), and water intrusion In addition, these areas aresubject to a higher potential for organic growth and staining due to prolongedwet periods and water rundown

For durable EIFS construction, the use of EIFS as a parapet cap should beavoided, even if the width of the parapet or cornice is limited and slopes aredesigned into the assembly Parapets are exposed to more severe weathering andtend to experience higher stresses than other wall areas These conditions tend tocause erosion and cracking in EIFS lamina installed at parapet caps, especiallyatinside or outside corners, as seen inFig 5 Damage can also occur from accessequipment used for window washing or wall-maintenance efforts on portions ofthe wall below the cornice In barrier EIFS, the water resistance of the system isderived from the continuityof the base coat; water can penetrate the EIFS atthese cracks, resulting in decreased durabilityand possible water intrusion intothe building or under the roof assembly It is typically recommended to installmetal coping over these types of horizontal surfaces Although installation of EIFS

EIFS cladding.

HORST, DOI 10.1520/STP158520150004 21

as a parapet cap or cornice is not specifically prohibited in the ASTM documents,many manufacturers’ details require installation of a separate cap on the surfaces

as well In addition, ASTMC1397-13[2] implies that a separate cap should be stalled by stating that the cap should be of corrosion-resistant material and in-stalled as soon as practical after the EIFS For new construction, the designershould specify and detail a durable material for the parapet cap or cornice Thiswill usually require installation of blocking to provide a base into which the cap

adjacent to the crack.

can be anchored In addition, a WRB should be installed under the cap thatintegrates the roofing material and the WRB for the wall or the basecoat in a bar-rier EIFS assembly In existing construction, removal of the EIFS may be neces-sary to permit evaluation of the substructure in order to install a separate parapetcap or cornice.

Many other horizontal or low-slope surfaces are often found on buildings,including recessed window ledges—as shown in Fig 6—and architectural trimelements These surfaces can allow water to accumulate, and in some locales, iceand snow can build up on these surfaces, even if a positive slope is provided Theseconditions can reduce the service life of the EIFS, often enable water leakage intothe interior of the building, and can result in deterioration of the substrate, asshown inFig 7 In order to promote durable EIFS-clad buildings, EIFS should beinstalled with a minimum slope of 6 in within 12 in In addition, the width of thesloped surface should not exceed 12 in These limitations correspond with thoseprovided in AnnexA1 of ASTMC1397-13 [2] For new construction, details should

be provided that clearly indicate these minimum slopes and maximum dimensions.Critical locations include interior and exterior corners where the slopes are moredifficult to maintain If a low-sloped surface larger than 12 in is desired, the EIFSshould be covered with a metal cap Care must be taken to integrate the cap with

HORST, DOI 10.1520/STP158520150004 23

the WRB or EIFS assembly Increasing the durability of an existing EIFS-clad ing with horizontal projections will often require installation of a metal cap orremoval of the EIFS and installation of a sloping surface—as shown inFig 8—thatmeets the previously discussed requirements.

build-Substrate Compatibility Considerations

For EIFS to be durable, the substrate to which it is attached must also be compatibleand constructed in accordance with established criteria ASTM C1397-13 [2] pro-vides several criteria for EIFS substrates, ranging from deflection limitations toidentifying specific acceptable substrates Manufacturers may also have additional,more stringent criteria for the substrates Factors relating to the substrate thatreduce the durability of EIFS in new construction are rare, and when they occur aretypically caused by construction errors However, substrate compatibility issues canreduce the durability of EIFS in overcladding or recladding projects The primaryissue affecting the compatibility of the substrate for these projects is the condition

of the substrate

As discussed in ASTM C1397-13 [2], deteriorated gypsum sheathing, as trated in Fig 9, and decayed plywood or oriented strand board (OSB) sheathingshould be removed and new sheathing installed prior to recladding with EIFS Theframing should also be evaluated, and any decayed wood studs or severely corrodedmetal studs should be repaired If overcladding is under consideration, theseelements must be evaluated to ensure that the EIFS is supported by a sound

substrate in order to attain a durable EIFS-clad building Failure to address rated sheathing or framing conditions can significantly decrease the life expectancy

deterio-of the EIFS cladding

The condition of the substrate is also of vital importance with concrete,masonry, and Portland cement plaster (stucco) substrates, particularly if the EIFS

is intended to be adhered Loose or deteriorated concrete is a poor substrate forEIFS The deteriorated concrete should be removed and concrete repairs should beinstalled and allowed to cure prior to installing new EIFS Masonry substrates aresimilar in that any deteriorated masonry should be removed and adequate repairsinstalled in order to provide a sound and level substrate for the EIFS When apply-ing EIFS over stucco, it is important to determine the condition of the materialsupporting the stucco, in addition to the condition of the stucco itself, prior toinstalling new EIFS If the condition of a concrete, masonry, or stucco substrate isquestionable, or if repairs cannot be performed, mechanical attachment of the EIFSshould be considered Appropriate repairs of deteriorated masonry, concrete andstucco substrates, or mechanical attachment of the EIFS to a sound substrate canprovide a long-lasting EIFS reclad or over-clad project

ledge.

HORST, DOI 10.1520/STP158520150004 25

Compatibility of Water-Resistive Barriers

The attachment method for the insulation must be compatible with the WRB inorder for an EIFS with drainage cladding to be durable A wide variety of EIFSproducts are available,with a wide variety of WRBs and attachment methods.Depending on the system,the WRB could consist of a fluid-applied product or asheet product

In the case of the sheet products,priming of the substrate and shingle-lapping

of individual WRB segments and the WRB and flashings are critical to the bility of the system This installation will prevent incidental water that penetratesthe EIFS from entering the building and will direct any water to the exterior face

dura-of the EIFS Also,these systems usually require mechanical attachment dura-of theinsulation to the substrate,as shown in Fig 10,because the sheet WRBs maynot be compatible with the adhesives commonly used to adhere the insulation inEIFS Although these mechanical attachments penetrate the WRB,EIFS can bedurable if designed and constructed to prevent excessive water from penetratingthe exterior face of the wall

It is important that all components of an EIFS be produced by,or approved by,the manufacturer of that system One area in which this distinction is essential is in

recladding project.

the installation of the WRB in EIFS with drainage In these systems, the insulation

is adhesively applied, and the WRB is part of the manufactured system Application

of a fluid-applied WRB that is compatible with the adhesive is crucial to the bility of the EIFS Mixing products from different manufacturers could result inreduced bond strengths or incompatibilities that ultimately could end in systemfailures

dura-In addition to ensuring that the WRB is a compatible part of the EIFS,fluid-applied WRBs must be installed in accordance with the manufacturer’srequirements in order to provide a durable EIFS These requirements often includeminimum application thicknesses and treating joints in panelized substrates, asshown in Fig 11 The flashings installed must also be compatible with the WRB.Most fluid-applied WRB manufacturers supply membrane flashings that are com-patible with their systems The use of incompatible flashing materials can result inloss of adhesion, which can lead to water intrusion into the building Adequatedesign and installation of compatible WRBs and flashings greatly enhances thedurability of EIFS-clad buildings by preventing water leakage into the building ifincidental water bypasses the base coat layer through penetrations, failed sealants,

HORST, DOI 10.1520/STP158520150004 27

EIFS Although the possible terminations and interfaces are practically limitless,several common poorly designed and constructed details significantly reduce theservice life of the EIFS, including terminations at grade, windows and other largepenetrations, smaller penetrations, integration with abutting cladding materials, androofing interfaces.

TERMINATION AT GRADE

Improper detailing or installation of the EIFS terminations at grade, whetherhardscaping or landscaping is present, are frequent causes of deterioration in theEIFS or substrate These concerns arise in both barrier EIFS and EIFS with drain-age applications Frequent deleterious conditions relating to EIFS termination atgrade include exposed sheathing or framing elements, inadequate backwrapping,and terminations too close to grade or extending below grade

A common issue in framed wall construction is for the framing or sheathingelements to be exposed at the base of the wall This issue can occur regardless of thecladding system and is often caused by variations or inaccuracies in the location ofthe edge of a concrete slab-on-ground or foundation wall supporting the framing

or in the location of the framing itself Even if these elements are covered by thecladding, exposed edges can absorb water (in the case of wood framing andsheathing) or provide a surface for condensation to occur (in the case of metalframing) Either of these conditions can eventually lead to decay, corrosion, or dete-rioration of the sheathing and framing elements Although the framing and sheath-ing are not part of the EIFS installation, degradation of the framing or sheathingwill decrease the durability of the EIFS ASTMC1397-13 [2] requires assessment ofthe substrate prior to application of the EIFS In addition, project specifications

typically require the EIFS installer to inspect the substrate prior to performing theirwork to verify the backup meets system requirements Installation of EIFS signifiesacceptance of the framing and sheathing installation The EIFS installer shouldrequire that unsuitable conditions be rectified prior to installation With theincreased use of fluid-applied WRBs, the instances of exposed sheathing and fram-ing at the base of the wall are less frequent because the WRB installer usually coversthe sheathing edge and exposed framing with the WRB.

Inadequate backwrap, or other means used to protect the terminating edge ofthe insulation board, continues to be an issue that negatively impacts the durability

of EIFS Although this can be a concern at any location where the EIFS terminates,such as window and door openings, it frequently occurs at the base of the wall

A common defect related to backwrapping is inadequate coverage of the base coatover the reinforcing mesh on the underside of the insulation board In both tradi-tional barrier EIFS and EIFS with drainage, failure to backwrap leaves the insulationvulnerable to moisture exposure, insect infestations, impact, and other sources ofdamage that decrease the durability of the EIFS cladding ASTM C1397-13 [2]addresses protection of the insulation board edges by requiring these edges to be

“wrapped with either the base coat and reinforcing mesh or trim, or as specified bythe EIFS manufacturer.” Similarly, ASTM E2511-09 [3] identifies wrapping theexposed edges of the insulation or using trim as principles that should be followedwhen designing details That standard also indicates that details should be providedfor these terminations Another issue, which is limited to barrier EIFS systems, isthat without adequate backwrapping the sealant along the bottom edge of the EIFSwill not have an adequate bond surface This condition could permit water tobypass the barrier and damage sheathing or framing elements Although variousmethods exist to backwrap, prewrapping of insulation board prior to installation onthe wall yields more consistent results In addition, prewrapping reduces the possi-bility of interrupting the drainage plane in an EIFS with drainage application.Adequately backwrapped terminations protect the edges of the insulation and, inbarrier EIFS applications, provide a sound substrate for sealant adhesion Both ofthese benefits foster durable EIFS installations

Terminating the EIFS an appropriate distance above grade is also an importantfactor in constructing durable EIFS Although the two ASTM documents referred

to throughout this paper do not provide a recommended distance for terminatingthe EIFS above grade, manufacturers typically limit the proximity of their products

to grade These minimum distances for termination above grade reduce the risk ofdirect water exposure and provide clearance for maintenance of the finish gradeand base seals (where present) Terminating EIFS too close to grade, or below grade,can also interfere with the ability of EIFS with drainage to function properly byblocking the drainage capabilities of the system Any of these conditions could neg-atively affect the durability of the EIFS The author recommends terminating theEIFS at a minimum of 8 in above grade at landscaped areas and a minimum of 2

in at hardscaped areas, such as concrete sidewalks or plazas Special circumstances,

HORST, DOI 10.1520/STP158520150004 29

such as a reclad project with existing grades that do not permit these minimums,may require modifications to these distances; however, care must be taken in thedesign and detailing of these conditions, and the manufacturer should be consulted.Regardless of clearance dimensions, grade and paving should always be slopedaway from the exterior enclosure EIFS should not be installed below grade, asshown inFig 12, even in a reclad situation where the previous cladding system mayhave extended below grade If necessary, modifications should be made to enablethe EIFS to terminate above grade One common modification is the construction

of a new concrete curb, as shown inFig 13 Terminating the EIFS an adequate tance above grade is critical to a durable EI FS cladding

dis-WINDOWS AND OTHER PENETRATIONS

The development of quality details for the integration of windows and other tions through the EIFS and installing EIFS in accordance with those details areperhaps the most critical aspects to providing durable EIFS ASTME2511-09 [3] dis-cusses the need for details to be provided at openings and penetrations in the EIFS.Poor integration of windows and other penetrations has frequently been the reasonfor failures in EIFS-clad wall assemblies These failures typically include water leak-age, damage to interior finishes, and deterioration of exterior sheathing and wallframing, all of which reduce the durability, or perceived durability, of the EIFS

A good understanding and appreciation of the manner in which water tion is resisted or controlled is imperative to the development of details for integra-tion of windows and other penetrations and to the application of these details.Because the methods of water penetration resistance and control differ betweenbarrier EIFS and EIFS with drainage, the integration details often vary between thetwo systems In addition, window assemblies can be either internally drained or

surface barrier systems, which may require different detailing As implied by theterminology, surface barrier window systems resist all water penetration at the outersurface of the window assembly These window assemblies typically incorporatesealants between the glazing and framing components and at all frame joints Inter-nally drained window assemblies anticipate that incidental water will penetrate theouter surface of the assembly These systems provide a means of collecting thiswater and drain it back to the exterior Drained window assemblies usually incorpo-rate gaskets between the glazing and frames and the exterior frame joints are nottypically sealed Internally drained windows include weeps or other means to drainincidental water to the exterior of the wall assembly.

Barrier EIFS

The key factor in integrating windows and other penetrations into traditionalbarrier EIFS-clad walls is that all water must be resisted at the level of the reinforcedbase coat Water that penetrates beyond the base coat in a barrier EIFS-clad build-ing can have deleterious effects on the durability of the EIFS and other wall compo-nents unless a secondary barrier is incorporated into the wall assembly In barrier

grade (Some waterproofing and structural elements are not illustrated).

HORST, DOI 10.1520/STP158520150004 31