Phenolic Insulation and the Building Envelope | IIBEC

Phenolic Insulation and the Building Envelope

Donald W. Kilpatrick • INSPEC, Inc. • Milwaukee, WI
Michael G. Taylor, Esq. • Leonard, Street & Deinard • Minneapolis, MN
ABSTRACT
Most are aware of the well documented characteristics of phenolic insulation when
interfaced with structural steel roof decking. Millions of square feet of existing roof
systems have been removed to facilitate steel deck remediation, overlay, and in some
instances, replacement, due to the corrosion that has occurred because of the known
acidic properties of the material. In recognition of the problem, the two manufacturers
of the product initiated class action settlements to accommodate the anticipated flood
and settled a massive class action lawsuit brought on behalf of roof owners with phe¬
nolic foam insulation laid over steel roof deck. The settlement provided some relief to
those owners within the class, but didn’t redress any problems owners might have with
phenolic foam insulation that was not laid over steel roof deck.
This paper will discuss recent findings suggesting that, in the presence of phenolic
insulation, the integrity of other structural steel components of the building envelope
have been compromised – more specifically, concealed steel elements such as shelf
angles and brick ties. The sampling and subsequent testing of these materials has estab¬
lished a chemical link between the phenolic insulation and the observed volumetric
expansion, corrosion, and failure of these building envelope features.
Donald W. Kilpatrick
Don Kilpatrick has been employed with INSPEC, Inc., since . During his tenure in the laborato¬
ry environment, he has evaluated a broad range of roofing systems and components, with an emphasis on
construction defects. Don’s observations and analysis of these components and assemblies has been uti¬
lized in compliance and workmanship testing on both new and existing construction and failure investiga¬
tions. Most recently, he has been assisting building owners with their specific needs related to compliance
with fagade ordinance inspections.
Michael G. Taylor
Michael G. Taylor is a shareholder and chair of the Construction Law Group of Leonard, Street &
Daimond, Minneapolis, MN. He has extensive experience negotiating engineering, design, construction
management, construction, and design/build contracts, and he has represented architectural, engineering,
roof consultant, construction manager, developer, owner and contractor clients in construction-related lit¬
igations, arbitrations and mediations throughout the country. Mike is active in the litigation and construc¬
tion insurance sections of the American Bar Association. He has written and lectured extensively on vari¬
ous construction, litigation, and insurance issues, and is an active member of AIA, RCI, AGC, and ABC.
Kilpatrick and Taylor —29
Phenolic Insulation and the Building Envelope
This paper will discuss recent findings suggesting
that, in the presence of phenolic insulation, the integrity
of structural steel components such as shelf angles and
brick ties may be compromised. The sampling and subse¬
quent testing of these materials has established a chemi¬
cal link between the phenolic insulation and the observed
volumetric expansion, corrosion, and failure of these
building envelope support mechanisms. As a result, cost¬
ly wall repairs may sometimes be required in conjunction
with reroofing. Also presented are the legal effects of
these findings, and the potential recourse against the
manufacturers of phenolic insulation that may still be
available to building owners.
REVIEW
Most are aware of the well-documented, less-thandesirable
characteristics of phenolic insulation when in¬
terfaced with structural steel roof decking. Millions of
square feet of existing roof systems have been removed
to facilitate steel deck remediation, overlay, and in some
instances replacement, due to the corrosion that has
occurred because of the known acidic properties of the
material.
In recognition of the problem, the two manufacturers
of the product initiated class action settlements to accom¬
modate the anticipated flood claims. Due notice was pro¬
vided through a media blitz that included newspapers,
magazines, and television ads, educating and advising
building owners of the potential problems associated
with phenolic products. Both manufacturers presented
case studies demonstrating the varied levels of corrosion
that could be expected. They also offered economic data
suggesting the financial burden of the costly re-roofing
should acknowledge depreciation, or useful life of the
existing assembly. Their efforts satisfied the court and an
agreement or settlement class was derived.
Building owners who were fortunate enough to opt
out of the class put themselves at an advantage, such that
they could potentially improve their settlements beyond
that offered within the class. The settlement terms are
clear in presentation as they relate to eligibility require¬
ments. These requirements are largely based on the type
and arrangement of roof system components in the
assembly. For example, phenolic-installed, direct-to-steel
deck in either built-up or single-ply configurations would
be considered an eligible claim {Photos 1 and 2). The
manufacturers have turned a blind eye to some steel deck
installations that incorporated a vapor retarder. The pres¬
ence of the vapor retarder is cited as providing adequate
protection for the steel deck. Moreover, specific to dis¬
cussion in the body of this paper, the settlement terms
state in part that, “the following persons are not included
in the settlement classes:… (b) persons whose roof sys¬
tem and roof deck are entirely non-metal .”
It is widely accepted that in the presence of moisture,
the corrosion is decidedly worse. This suggests that the
moisture is the vehicle or transport mechanism for the
acid, from the insulation in board form to the underlying
steel deck. Those familiar with the phenomenon are
quick to recognize the broad spectrum and wide variabil¬
ity of corrosion that can be expected. A sharp contrast of
conditions, representing severe rust to near pristine con¬
ditions, has been observed adjacent to one another in the
Photos 1 and 2: Contrast in conditions that can be expected when phenolic insulation is installed over structural
steel decking.
Kilpatrick and Taylor— 31
Photo 3: The protection offered by a vinyl vapor
retarder at this inspection opening is questionable, as
the deck conditions presented no more than one foot
apart range from near pristine to severely corroded.
field of the roof (Photo 3). In most instances, the insula¬
tion installed in areas of severe localized corrosion are
laden with moisture. As would be expected, the level of
corrosion varies as the insulation component moves to¬
ward its equilibrium moisture content, or that determined
by the service environment and ambient conditions.
humidity of the manufacturing facility was 62% and the
building was pressurized. The roof system consisted of
the following components from the deck up:
Roof deck: Structural steel
Vapor retarder: Reinforced paper laminate
Base layer
insulation: Mechanically fastened 1.7 in. phenolic
Top layer: 1/2 in. perlite mopped in asphalt
Membrane: Four-ply asphalt, fiberglass felts with
aggregate surfacing
Square footage: Approximately 300,000
Observations
The expansion joint wood blockings ran perpendicu¬
lar to the direction of the steel deck, centered over a 3/4-
in. gap in the deck. The sheet metal cap and counter
flashing covering the expansion joint were rusting. At the
inspection opening, a wash of warm air came out of the
building and condensation was noted on the vinyl draped
over the top of the wood blocking. The insulation adja¬
cent to the inspection opening was dry.
The following discussion presents our observations
and findings made on two phenolic projects. The first
project was initially considered a routine, “within the
class” claim with phenolic insulation installed over steel
deck, vapor retarder inclusive. The second project began
as a facade inspection required by municipal code.
PROJECT NO. 1
On a recent re-roofing project driven by the presence
of phenolic insulation, it was noted that some above-roof
surface sheet metal accessories were exhibiting varied
Another roof system feature was the numerous curbs,
installed as part of the original construction, intended to
accommodate the owners’ needs relative to the pre¬
dictable changes in occupancy. These curbs were wood
framed and mechanically attached to the deck. The steel
deck and vapor retarder were continuous through the
confines of the curb, with the base and top layer of insu¬
lation terminating at the outside face of the curb. The
curbs were in-filled with fiberglass batt insulation, cov¬
ered with 3/4″ plywood, a single layer of plastic sheeting
and a 24-gauge galvanized metal cap (Figure 7). Severe
levels of corrosion.
More specifically,
galvanized cap and
counter-flashing,
items not in direct
contact with the
offending material,
were corroding.
These components
of the assembly
were installed in
conjunction with the
built-up roof system
as part of the origi¬
nal construc¬
tion. The measured
interior relative
VAPOR RETARDER
/T\ FIGURE I
NOecALE
MTBWW RM • *3*
CCNOBtfiATICN • UNIT CURB6
Kilpatrick and Taylor— 32
Photo 4: Excessive corrosion of sheet metal accessories
(cap flashing) not in direct contact with phenolic insu¬
lation. Free moisture, attributed to condensation, was
present within the confines of the curb.
Photo 5: Wall system movement at the parapet/roof slab
interface resulted in the meandering upper limits of the
balustrade capstones.
corrosion was observed on the underside of the sheet
metal cap (Photo 4). Condensation was also noted at
these locations. The insulation around the curb was
essentially dry.
These observations suggest that the movement of air
through the building envelope, more specifically the steel
deck flutes discharging into deck openings at the expan¬
sion joint and curbs, may be a sufficient transport mecha¬
nism for the released acids from the adjacent, essentially
dry insulation. In this instance, the acids have migrated
to locations subject to condensation due to breaches in
the assemblage of roof system components. This is sup¬
portive of the theory that essentially dry phenolic insula¬
tion may contribute to the corrosion of steel in contact
with and close proximity to the offending materials. The
moisture content of phenolic insulation, that identified as
the transport mechanism for the known acidic properties
of the material, need not be in excess of equilibrium or
that established by the service environment of the instal¬
lation.
It is worth mentioning that the insulation manufac¬
turer dispatched its claim specialist to this project a num¬
ber of years before the owner decided to move forward
with the remediation. The expert reportedly made one
inspection opening, witnessed the presence of the vapor
retarder, and left the project. Their complacency worked
to this owner’s advantage in successfully negotiating
more favorable settlement terms.
PROJECT NO. 2
This author’s firm was retained to perform a critical
examination of facade components on a building in the
upper mid-west. The structure was ten stories with the
exterior cladding consisting of a single wythe of brick
mechanically fastened to CMU back-up wall. An insulat¬
ed cavity wall was present. A brick parapet wall extended
approximately 3 ft. 6 in. above the horizontal plane
established by the poured concrete roof deck (Photo 5).
A series of limestone-clad, bay window assemblies are
present at regular intervals across each elevation (Figure
2).
Kilpatrick and Taylor— 33
Photo 6: Previous caulking repairs at open joints and
cracks of the brick in-fill between the window bays.
Photo 7: At outside corners, the established horizontal
pattern of caulking repairs at open joints was supple¬
mented by additional vertical cracks.
Observations
During the facade inspection, it became evident that
the brick veneer was exhibiting concentrated levels of
distress and out-of-plane conditions at the juncture of the
roof deck and outside face of the parapet wall {Photos 6
and 7). Similar distress conditions were observed across
the cut-limestone cladding at the window heads (Photo
8).
A series of inspection openings in areas of localized
distress confirmed significant corrosion of the shelf
angles (Photos 9 and 10). The conditions were most
prominent at the tenth-floor roof slab and parapet inter¬
face, with conditions improving at the juncture of the
eighth-floor slab and brick veneer (Figure 3). On the bal¬
ance of similar floor slab interfaces with the brick
veneer, the deflection was present, but not as pronounced
Photo 8: Repetitive pattern of horizontal cracks across
the limestone-clad window heads. The distress condi¬
tions presented were typical of the building’s four pri¬
mary elevations.
Photo 9: A severely corroded shelf angle, and subse¬
quent rust jacking, was determined to be the apparent
cause for the out-of-plane conditions observed at the
brick in-fill between the window bays.
Photo 10: Volumetric expansion of the steel shelf
angles at the parapet/roof slab interface.
Kilpatrick and Taylor— 34
as that of the tenth floor. The subsequent shift of loads
from the upper limits of floors 10-8 was distributed to
the balance of the shelf angles mechanically fastened to
the outside face of the floor slabs on floors 7 – 3. As a
result, the integrity of the anchorage mechanisms was
compromised. It was determined that replacement of the
shelf angles and brick veneer would be required on floors
3 – 10.
Upon completion of the fagade inspection in the fall
of , a report was issued in which the conditions
were described as “safe with maintenance and repair,”
subject to repairs by -04. Extending the repair win¬
dow anything beyond the -04 construction season
would have presented an “unsafe and imminently haz¬
ardous condition,” as upwards of 60-70% section loss
had occurred at isolated locations in the shelf angles on
the upper limits of the building.
As part of the design survey required to develop bid¬
ding documents for subject wall repairs, it was deter¬
mined that the roof construction consisted of the follow¬
ing components from the deck up:
Roof deck: Poured concrete
Vapor retarder: Two-ply fiberglass set in asphalt
Base layer
insulation: 1.2 in. phenolic
Top layer: 1/2 in. wood fiber
Membrane: Four-ply fiberglass in asphalt
with aggregate surfacing
Given the accelerated levels of corrosion observed
on the shelf angles at the roof slab interface, the discov¬
ery of the phenolic insulation as a component of the
building envelope resulted in further investigation. As a
result, samples of corroded steel (rust pack) and phenolic
insulation were obtained from inspection openings at the
cut limestone-clad window head of the tenth floor and at
the shelf angle mid-span, between the window bays. The
samples were submitted to a forensic lab for chemical
analysis.
Samples of both the insulation and steel (rust pack)
were extracted in deionized water. Through Fourier
Transform Infrared (FTIR) Spectroscopy, used to analyze
the extracts , it was determined that the IR spectra was a
match for para-toluene sulfonic acid (PTSA). The mea¬
sured pH of the extracts ranged from 3.5 to 3.8. The
results of the testing concluded that the presence of the
PTSA on the corroded steel and in the residues was a
FIGURE 3
NO SCALE
clear indicator that the phenolic insulation contributed to
the corrosion of the steel. The low pH and conductivity
of the extract supports the findings that acids were
involved in the corrosion.
In contrast, a similar group of steel samples from
window head lintels and fire escape connections was
obtained from a nearby building known not to include
phenolic insulation as a component of the roof assembly.
Each of the samples was exhibiting varying levels of cor¬
rosion. The samples were subjected to the same series of
tests to determine if acids contributed to the corrosion
process. The measured pH of the extracts ranged from 6
to 7 (basically neutral), with no evidence to suggest that
acids (more specifically PTSA), contributed to the corro¬
sion.
Based on the above-mentioned lab results and the
apparent role of the phenolic insulation as catalyst for the
corrosion, leaving the phenolic in place was considered
an unacceptable risk. It was determined that complete
removal of the phenolic would be required prior to intro¬
ducing the new steel shelf angles that would be necessary
as part of the wall repair contract.
A temporary roof covering consisting of a torchapplied
modified was specified. The temporary roof
included a four-foot band of 1/8 in. per ft. tapered mater¬
ial at the outside parapet roof edge. This feature directed
Kilpatrick and Taylor— 35
Photo 11: Apparent breach in the two-ply vapor
retarder at the transition from the horizontal plane of
the roof deck and adjacent apparent wall. The tear in
the felt plies and gap between the roof slab and parapet
wall are present due to the corrosion of the shelf angle,
subsequent rust jacking, and upward movement of the
wall section. It is at these locations that free moisture
carried water soluble acids from the wet phenolic insu¬
lation into the wall cavity.
water to the interior roof drains, significantly reducing
the likelihood that water would be retained in the work
area soon to be occupied by the masonry contractor.
The removal of the existing roof provided the oppor¬
tunity to gather additional information related to the asbuilt
conditions of the roof assembly and its relationship
to the masonry features of the parapet. As previously
mentioned, there was a two-ply fiberglass vapor retarder
mopped in asphalt to the concrete deck. The felt plies of
the vapor retarder were turned up at the parapet wall
approximately 2 to 3 in. A large quantity of the phenolic
insulation was saturated, primarily that present to the
north, south, and east of the centrally located penthouse,
with moisture content in excess of 650% by dry weight.
That to the west of the penthouse was essentially dry.
It could be argued that the vapor retarder, installed
over a concrete deck, would provide adequate protection
for any steel that may be in close proximity to phenolic
insulation, wet or dry. However, on this project it was
determined that the portion of the vapor retarder that
continued through the transition from the horizontal
plane of the roof deck up the vertical surface established
by the interior of the parapet was largely void of mop¬
ping asphalt.
The lack of mopping asphalt, in conjunction with the
porous characteristics of fiberglass felts, results in a feltply
envelope in a critical location that is less than water¬
tight. It is at this location that the soluble acids carried by
the excess moisture that could no longer be retained in
the insulation made its way into the wall cavity, resulting
in the accelerated corrosion of the shelf angles {Photo
11). At no time since the roof was installed has the owner
reported disruption of occupancy due to water leakage
into the building interior, in spite of the large quantities
of wet insulation. Free moisture that could no longer be
retained in the saturated insulation moved laterally, fol¬
lowing the path of least resistance, discharging into the
wall cavity making contact with structural steel support
mechanisms for the limestone cladding and brick veneer
(Photos 12, 13, and 14).
Photo 12: Relationship of segmented shelf angle pro¬
viding support for the limestone cladding, outside face
of poured concrete deck, phenolic insulation, and relat¬
ed roof system components.
Photo 13: Overall poor condition of cast-in-place
receiver and anchor bolt for shelf angles at outside face
of poured concrete roof deck.
Kilpatrick and Taylor— 36
By the early s, some building owners who had
installed phenolic foam insulation over metal roof decks
began to notice corrosion problems on their metal decks.
The costs of replacing the roofing systems and repairing
or replacing the supporting metal decks were significant.
Roofing consultants and experts hired by the building
owners began to link the corrosion to the phenolic foam
insulation. However, early on, Beazer and JM often
either denied that the roof deck corrosion problem was
caused by their phenolic foam insulation, or simply
refused to adequately compensate the owners for their
repair or replacement costs. The inevitable lawsuits
against Beazer and JM followed.
Photo 14: The cracks in the outside face of the lime¬
stone cladding were caused by the rust jacking of both
the horizontal and vertical legs of the steel shelf angle.
The results of this investigation are supported by
sound mechanics and the known, industry-accepted, lessthan-
desirable performance characteristics of phenolic
insulation in the presence of moisture. As such, the larger
question is what happens beyond discovery? Do these
findings challenge the terms, conditions, and potentially,
the accepted limits of product liability? Is there any
recourse for an owner of a building currently exhibiting
wall distress conditions that can be attributed to the pres¬
ence of phenolic insulation? The following discussion on
legal issues will explore options that may be available to
building owners under current law.
LEGAL ISSUES
The History Of Phenolic Foam Litigation
From through early , two companies man¬
ufactured, distributed, and sold phenolic foam roof insu¬
lation to roofing wholesalers, contractors, and property
owners in the United States. Beazer East, Inc., formerly
known as Koppers Company, Inc. (Beazer), manufac¬
tured, distributed, and sold phenolic foam roof insulation
from through January 17, . Schuller
International, Inc., now known as Johns Manville
Corporation (JM), manufactured, distributed and sold
phenolic foam roof insulation from January 17, ,
through approximately March 31,1 992 . From
through early , Beazer or JM phenolic insulation
was installed on literally thousands of commercial,
industrial, and apartment buildings throughout the United
States.
The Phenolic Foam Class Action Lawsuit and
Settlement
In the mid s, some of these separate lawsuits
were consolidated by a Massachusetts federal judge into
a single class action captioned Sebago, Inc. and Flint
Village, LLC v. Beazer East Inc. f/k/a/ Koppers
Company, Inc, Johns Manville Corporation, et al, 18
F.Supp.2d 70 (D.Mass. ). Interestingly enough,
while the original lawsuits that were consolidated con¬
tained many “state law” claims against Beazer and JM
for negligent representation, negligence, strict products
liability, fraud, and breach of implied and express war¬
ranties, many of these claims were actually dismissed or
limited by the federal judge. The judge, however, did
allow the class action plaintiffs to proceed with their
claims under a federal statute known as the Racketeer
Influenced and Corrupt Organizations Act (RICO), based
upon alleged mail or wire fraud committed by Beazer
and JM in sending out “misleading” brochures and infor¬
mation.
In mid-June, , the federal judge entered an order
granting preliminary approval of a proposed settlement.
Building owners who would otherwise be included in the
class for settlement purposes were given until November
22, , to “opt out,” and pursue claims on their own.
In mid-December, , the proposed settlement was
given final approval. For purposes of the settlement, the
class members were all persons or entities who had not
opted out, and who, as of June 30, , owned an
“Eligible Property,” which was defined as a building on
which the phenolic insulation was installed over a metal
roof deck and within a built-up roofing system, a single¬
ply roofing system, or a shingled roofing system. The
class members, for settlement purposes, did not include
any building owners who had installed phenolic foam
over non-metal deck, or owners who had included phe¬
nolic foam within a metal roof system whose exterior
membrane was all metal.
Kilpatrick and Taylor— 37
Those who participated in the class action settlement
ended up signing global releases that released Beazer and
JM from any liability whatsoever with respect to the phe¬
nolic foam on their buildings. For example, in the Beazer
settlement agreement and release, the release language
broadly states:
Roof Owner does hereby release and forever
discharge Beazer… from any and all claims,
liabilities, rights, demands, suits, matters,
obligations, damages, losses or costs, actions
or causes of action, of every kind and
description, in law or in equity, that the Roof
Owner has, had or may have against Beazer
… whether known or unknown, foreseen or
unforeseen, accrued or which may hereafter
accrue, asserted or unasserted, latent or
patent, that is, has been, could reasonably
have been or in the future might reasonably
be, asserted by the Roof Owner against any
Beazer party, either in this Action, or in any
other action or proceeding, in this Court or
any other court or forum, regardless of the
legal theory, and regardless of the type or
amount of relief or damages claimed arising
from or in any way relating to the design,
manufacture, distribution, sale, handling,
written or oral instructions, specifications,
marketing, use, performance or any defects
or alleged defects of Beazer, PFRI, and any
replacement, repair, treatment, remedial
work, removal or disposal of the Roofing
System or Deck at the Building, or any part
thereof which have accrued or will accrue as
a result of having Beazer PFRI on the Roof
Owner’s Eligible Property (“Settled
Claim”)…
The form class action JM settlement agreement and
release contains similarly broad language.
Accordingly, building owners who settled with
Beazer or JM under the terms of the class action settle¬
ment are possibly barred from bringing any claim for the
new building envelope corrosion phenomenon identified
earlier in this paper. This is true even though arguably
the damage to the building envelope, as discussed in the
earlier portion of this paper, was not known at the time
of the settlement, nor even contemplated by any of the
plaintiffs in the class action. To be successful in any new
legal action against Beazer or JM, a building owner who
already released claims pursuant to the class action set¬
tlement would first have to prevail on an argument that
the class action settlement should be voided or reopened,
or, in spite of the express language of the signed release,
that the settlement and release did not cover damages for
the new claims.
Claims Against Beazer or JM by Building Owners
Who Opted Out of the Class Action or Who Were Not
Covered by the Class Action
For the most part, building owners who opted out of
the class action, but who settled with Beazer or JM on
their own, signed settlement agreements and releases
provided by Beazer and JM that also contained very
broad release language, which arguably bar any new
claims. The only building owners who do not face the
broad release language problem are those who have yet
to settle any claims with Beazer or JM, either inside or
outside the class action lawsuit.
Applicable Statutes of Limitations and Repose
In addition to the release language issue, another hur¬
dle to a possible recovery against Beazer and JM for the
phenomenon discussed earlier in this paper is state law
statutes of limitation and repose. Many, if not most
states, have statutes that will bar a building owner from
bringing a lawsuit for damage resulting from negligent
design, faulty construction, or defective materials after a
certain amount of time has passed. In Nevada, for exam¬
ple, the applicable statute of limitations provides that any
lawsuit based on a construction defect must be com¬
menced within three years after the defect is discovered
(NRS 11.190(3]). Further, the Nevada statutes of repose
provide that regardless of when (or even if) the defect is
discovered, any lawsuit based upon a patent (or obvious)
defect must be brought within six years after substantial
completion of the construction, and any lawsuit based
upon a latent (or hidden) defect must be brought within
eight years after substantial completion. (NRS 11.204-
205).
Most other states have similar statutes of limitation
or repose, although the time periods will vary somewhat
from state to state. In some states, claims otherwise time
barred by an applicable statute of limitation or repose
will be allowed to proceed if the owner can show fraud
or fraudulent concealment on the part of the defendant.
The legal point is that even if claims against Beazer or
JM have not been expressly released in a settlement, they
may be barred by the applicable state statute of limita¬
tions and repose. Roofing contractors and consultants
who discover conditions with the building envelope simi¬
lar to those discussed in the first sections of this paper
should recommend that the building owner immediately
Kilpatrick and Taylor— 38
consult with a lawyer to determine whether a timely
claim could be brought.
Third Party Issues
Depending upon the severity of the problem, a build¬
ing owner who discovers conditions with the building
envelope similar to those described in the first sections of
this paper may have to immediately initiate costly
repairs, whether or not there is a potential recovery from
the phenolic manufacturer(s) or others responsible for the
construction or design of the roofing system. A failure to
initiate repairs could result in significant additional dam¬
age to the building in the future. Further, if portions of
the building envelope crumble or fall away, this could
result in catastrophic loss or injury to third parties, either
in the form of third-party property damage, injury, or
death. If this were to occur in a situation where a build¬
ing owner knew, or should have known, about the prob¬
lem, but did nothing, significant additional (and unin¬
sured) liability could attach.
Roofing consultants who continue to discover pheno¬
lic foam on buildings should immediately alert their
clients (in writing) to the possibility of problems beyond
the corrosion of metal roof decks. Under certain condi¬
tions, it should also be recommended that structural
members that may have been exposed to the water solu¬
ble acids known to be present in the phenolic insulation
be inspected as well.
SUMMARY
The findings of this investigation suggest that the
difficulties associated with phenolic insulation may reach
much further than that accepted by the industry and so
far acknowledged and recognized by the manufacturers.
The manufacturers are quick to discount the claim, stat¬
ing they have never heard of their product resulting in
the described conditions/loss. Lack of previous knowl¬
edge alone is not just cause to dismiss a claim. With
most product-related claims resulting in loss, there is a
discovery phase which is a precedent-setting, defining
moment, supported by fact, that drives reaction to and
acceptance of the phenomenon as real.
The conditions described in this paper are driven by
special circumstances (high interior relative humidity,
saturated insulation). It is not being suggested that all
buildings with phenolic insulation will exhibit similar
problems. However, the testing performed to date indi¬
cates that the inert properties of phenolic insulation are
compromised by a continual release of para toluene sul¬
fonic acid (PTSA). The soluble acids are distributed to
susceptible areas of the building through the movement
of free moisture and perhaps by moisture-laden air mov¬
ing across the building envelope to condense elsewhere.
The migration of the acids through the building envelope
results in corrosion of steel elements that would typically
be thought of as not susceptible to damage. Buildings
with concrete decks and wall cavities are more likely to
be subjected to damage, as leakage to the building interi¬
or may not occur due to the monolithic nature of the roof
deck.
Kilpatrick and Taylor— 39

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