perform guard technical bulletins 12-10 - color€¦ · control communities to resist termites....

TECH BULLETIN

Subject:

Date:

Perform Guard No.

of 2Perform Guard no. 6006

6006

Foam-Control EPS has developed a treatment called Per-

from Guard for molded Expanded Polystyrene (EPS) which

creates a termite resistant product.

Through this development, Foam-Control EPS has con-

ducted numerous studies on the efficacy of termite resistant

Foam-Control EPS with Perform Guard.

Foam-Control EPS with Perform Guard Testing Summary

Borates have been widely utilized by the scientific and pest

control communities to resist termites. Numerous studies

have been completed by universities, government-spon-

sored agencies and industries showing the efficacy of bo-

rates for termites. Due to the effectiveness of the borates

and their low toxicity to humans and animals, Foam-Control

EPS elected to research the compatibility of borates with

molded EPS insulation products. Foam-Control EPS with

Perform Guard EPS is the result of the Foam-Control EPS

research and development effort.

Studies have been conducted to determine the resistance

of products produced with Foam-Control EPS with Perform

Guard to several species of termites. These studies include

force-feeding and long-term full exposure. Summaries

of each test completed are described. The results of the

Foam-Control EPS with Perform Guard test program dem-

onstrate resistance to termites in the environments where

these types of products will be utilized.

1. Termite Resistant Testing

A.) “Feeding and Survival of Subterranean Termites After

Exposure to Untreated and Borate Treated R-Control® Build-

ing Panels in Laboration, Gulfport, Mississippi, by Lonnie H.

Williams, Principal Entomologist, November 1991.

The testing was initiated to evaluate the termite resistance

of untreated panels and R-Control SIPs (Structural Insulat-

ed Panels) which utilized Foam-Control EPS with Perform

Guard cores and topically treated OSB skins. Panel seg-

ments measuring 6” x 6” were extracted from full size pan-

els and were exposed to both Reticulitermes flavipes (Kol-

lar) and Coptotermes formosanus Shiraki. A 6” x 6” sample

panel was placed in a large vessel on top of a sterilized brick,

which was placed in a moistened substrate. To each vessel,

several thousand termites from a single colony were added.

Each of the repetitions consisted of vessels with treated

panel and untreated panel segments.

Purpose:

To determine the efficacy of a treatment for SIPs which con-

tain Foam-Control EPS with Perform Guard and topically

treated OSB skins.

Results:

R-Control SIPs produced with borate treated EPS (Perform

Guard) and topically treated skins were protected from se-

vere feeding damage by the native species (Reticulitermes

flavipes) and the introduced species (Coptotermes formo-

sanus) of termites. The treated panels using Foam-Control

EPS with Perform Guard had complete kill of the Reticuli-

termes flavipes in 1 week and the Coptotermes formosanus

workers in 6 weeks while the untreated panels had over 80%

survival rates for both species after 6 weeks and exhibited

severe panel damage by the termites.

It was also found that Foam-Control EPS with Perform

Guard cores laminated to plain OSB (no topical treatment)

reduced weight loss and foraging tube construction as com-

pared to the completely untreated samples.

2. Insitu-Testing

A.) “Evaluation of Structures Constructed with Borate-Treat-

ed Components for Protection from Damage by Insects and

Decay Fungi” conducted by the United States Department

of Agriculture, Lonnie Williams, Principal Entomologist, and

William H. Sites, Plant Pathologist.

Foam-Control EPS with Perform Guard Testing - SIPs

January 2008

Foam-Control EPS products are manufac-tured by AFM Corporation licensees.

Copyright ©2010 AFM Corporation. All rights reserved. Printed in USA. Foam-Control, Perform Guard, andControl, Not Compromise are trademarks of AFM Corporation, Lakeville, MN.

CONTROL, NOT COMPROMISE.®

www.foam-control.com

Three structures erected utilizing R-Control SIPs made with

Foam-Control EPS with Perform Guard cores were built by

the USDA to monitor borate treated construction compo-

nent resistance to damage by wood damaging subterranean

and drywood termites and decay fungi. The first structure

was erected in November of 1991, at the Forest Sciences

Laboratories in Gulfport, Mississippi. The second structure

was built in January 1992 in a park in Jacksonville, North Car-

olina, and the third structure was built November 1993 in the

Oregon State University Research Forest, Corvalis, Oregon.

Purpose:

To conduct a long-term insitu exposure and monitor the re-

sistance of R-Control SIPs produced with Foam-Control EPS

with Perform Guard.

Results:

None of the treated structures have termite damage. Non-

treated structures built on the sites exhibited termite activ-

ity.


TECH BULLETIN

Subject:

Date:

Perform Guard No.





6007

Foam-Control with Perform Guard Testing - Material Properties

January 2008

Foam-Control has developed a proprietary treatment for

Expanded Polysytrene (EPS) which makes EPS resistant to

termites. AFM markets the product as Foam-Control EPS

with Perform Guard®. Testing has been done both in the

laboratory and field.

In addition to field and laboratory exposure tests, Foam-

Control has conducted plant processing procedures, physi-

cal property testing, and coordinated system compatibility

studies.

Processing Procedures

Foam-Control, in cooperative work with its licensed facilities,

has developed the processing techniques for the manufac-

ture of Perform Guard EPS product that meets or exceeds

the requirements of ASTM C578, “Standard Specification

For Rigid, Cellular Polystyrene Thermal Insulations”.

Physical Tests

Underwriters Laboratories has evaluated Foam-Control EPS

with Perform Guard for physical performance under appro-

priate ASTM Standards. Flexural Testing (ASTM C203) of

Perform Guard EPS showed strengths equal to or greater

than minimum standards. Compressive Testing (ASTM

C165) showed strengths equal to or greater than minimum

standards. Density Testing (ASTM C303) showed densities

equal to or greater than minimum standards. Perform Guard

EPS is a listed UL material.

In-Plant Testing

The Quality Assurance procedures of Foam-Control’s Third

Party Quality Control Program call for in-plant testing of

each lot of material. Foam-Control Licensees have been

testing Perform Guard EPS under the guidelines of UL QC

Program. These tests qualify daily production runs of Foam-

Control EPS with Perform Guard to the critical standards of

ASTM C578.

Fire Performance

Foam-Control submitted Foam-Control EPS with Perform

Guard samples to Underwriters Laboratories for fire evalu-

ation. UL 723 “Test for Surface Burning Characteristics of

Building Material” tests (also known as ASTM E84) were

run. The results showed that Foam-Control EPS with Per-

form Guard has a similar flame spread and smoke developed

rating, when compared to industry standard modified EPS.

Addition full scale testing conducted on systems, such as

R-Control® Structural Insulated Panels, using Foam-Control

EPS with Perform Guard, demonstrated passing fire perfor-

mance.

Systems Compatibility

Compatibility studies by various adhesive manufacturers and

independent laboratories have shown that adhesive lamina-

tions using Perform Guard do not differ from untreated EPS

foam. Corrosion testing, using the Kesternich Cabinet pro-

cedure, has shown no corrosion to metal.

Note: Foam-Control EPS with Perform Guard has been test-

ed against termites. A list of specific species on file. Foam-

Control EPS with Perform Guard is not a barrier system, but

should be used as a component in a total insect manage-

ment program.

TECH BULLETIN

Subject:

Date:

Perform Guard No.





Foam-Control EPS with Perform Guard is Expanded Poly-

styrene which is treated to resist termites. This product is

produced by incorporating a naturally mined mineral into

Foam-Control EPS with Perform Guard product. However,

many individuals ask “How does it work?” and “Why is it ef-

fective?”.

Basically, Foam-Control EPS with Perform Guard is de-

signed to resist termites from creating a community within

the insulation. It is also designed to limit tunneling through

the Foam-Control EPS with Perform Guard material for ex-

tended periods. The borate derivative contained within the

Foam-Control EPS with Perform Guard acts as a bacterial

agent against the gut fauna that break down cellulose in

termites. For the borate derivative to act effectively, the

termites must ingest it or at a minimum, masticate (chew)

the Foam-Control EPS with Perform Guard. Therefore, there

may be some minor excavating of the Foam-Control EPS

with Perform Guard.

The termites must come in contact with the material before

they can determine that the material is treated. When this

occurs, two scenarios follow: The termite may continue to

excavate the material for some time, then succumb to the

deleterious effects of the borate material... or the termite

will elect to move away from the inhospitable environment

presented by the Foam-Control EPS with Perform Guard.

Foam-Control EPS with Perform Guard is not a repellant, nor

is it a contact insecticide. Through the life of the Foam-

Control EPS with Perform Guard it is probable that the ma-

terial will be visited from time to time. However, the borate

additive prevents continued attacks and helps to retain the

insulation’s serviceability.

Note: Foam-Control EPS with Perform Guard has been test-

ed against termites. A list of specific species on file. Foam-

Control EPS with Perform Guard is not a barrier system, but

should be used as a component in a total insect manage-

ment program. Insects may enter in through other access

areas.

Foam-Control EPS with Perform Guard and How it Works

January 2008

6008

TECH BULLETIN

Subject:

Date:

Perform Guard No.





Foam-Control EPS with Perform Guard was subjected to

accelerated moisture/mold exposure testing to gauge its

degree of mold resistance. Testing was based upon ASTM

D3273-00, “Standard Test Method for Resistance to Growth

of Mold on the Surface of Interior Coatings in an Environ-

mental Chamber.” This testing involves exposing the Foam-

Control EPS with Perform Guard to mold in an high humid-

ity environment, approximately 90% RH. In addition to the

testing of Foam-Control EPS with Perform Guard sample,

samples of southern yellow pine were tested as a control.

At the end of the 3 month test, the growth of mold (Tricho-

derma and Aspergillus) was obvious on the southern yellow

pine. NO mold growth was present on the Foam-Control

EPS with Perform Guard. Please also refer to Technical Bul-

letin eps. no 1004.

Foam-Control EPS with Perform Guard - Testing for mold Resistance

January 2008

6009

Southern Yellow Pine

with Mold Growth

Foam-Control EPS

with NO Mold Growth

TECH BULLETIN

Subject:

Date:

Perform Guard No.

Page 1 of 9Perform Guard no. 6010

6010

Foam-Control EPS with Perform Guard termite resistant

expanded polystyrene (EPS) is recognized in code evalua-

tion reports for below grade applications in regions of very

heavy termite pressure. Foam-Control EPS with Perform

Guard received this recognition through extensive below

grade in-situ testing over a period of 5 years at three termite

testing locations in the southern U.S. This bulletin provides

a brief description of the testing along with pictures of the

test results.

Three test plots were selected for the evaluation of Foam-

Control EPS with Perform Guard. The test plots were lo-

cated in Georgia and Mississippi. These plots are within the

region defined as very heavy termite pressure by the model

building codes. Foam-Control contracted with a third party

testing firm, Rich Mountain, to conduct all testing and report

all test results.

The testing was conducted following a test method devel-

oped jointly by Rich Mountain and Foam-Control. The test

method was modeled after AWPA E-7-93, “Standard Meth-

od Of Evaluating Wood Preservatives By Field Tests With

Stakes.” The testing consisted of EPS samples adhered with

construction adhesives/sealants to a concrete block. This

geometry was selected to mirror below grade insulation of

concrete/masonry walls. The detailed test method is avail-

able from Foam-Control upon request.

The samples geometry was such that the EPS were installed

adjacent to below grade bait wood. This was intended to

accelerate the exposure to termites by providing an large

initial food source for the termites. A second piece of bait

wood was installed above the sample to evaluate the extent

that termites would excavate and tunnel through EPS.

Attached to this bulletin are pictures from our testing. These

include the sample fixture geometry, test plots, and cross

sections of excavated EPS samples.

The performance of the Foam-Control EPS with Perform

Guard sample is quite dramatic when compared to untreated

EPS. Untreated EPS shows very obvious damage resulting

from extensive excavation and tunneling. In contrast, Foam-

Control EPS with Perform Guard shows very little damage.

The extensive testing conducted on Foam-Control EPS with

Perform Guard has led to Perform Guard being the only rigid

foam recognized for application in areas of heavy termite

pressure.

Foam-Control EPS Perform Guard Testing

January 2008


TEST FIXTURE - replicates below ground applications.

TEST FIXTURE - Prior to installation showing underground baitwood base toattract termites to site. Canister cover to protect termite activity.

Above groundbaitwood

Solid concrete capblock

Rigid foaminsulation

Underground baitwood214 cubic inches ofwood

8 inches aboveground

groundline

4 inches below

1-1/4 x 1-1/2 x 7-1/4 inchescross pieces


Field installation of test textures - Stone County, Mississippi.

Field installation of test textures - Griffin, Georgia.

of 9

#45 TEST FIXTURE - Examination of of non-treated EPS after 3 years exposure.Highland Site, Mississippi.

#45 TEST FIXTURE - cut open to reveal extensive termite damage.

Perform Guard no. 6010


#45 TEST FIXTURE - Close-up shows active termites.

#45 TEST FIXTURE - Close-up shows extensive termite damage.


#45 TEST FIXTURE - Close-up shows termite nesting galleries formed innon-treated EPS.

#45 TEST FIXTURE - Close-up shows nesting infestation of termites.


#64 TEST FIXTURE - cut open to reveal limited termite damage.

#64 TEST FIXTURE - Examination of Perform Guard EPS after 3 years exposure.Highland site, Mississippi.


#64 TEST FIXTURE - Close-up shows slight termite damage.

#64 TEST FIXTURE - Close-up shows no termite damage.





Page 9 of 9Perform Guard no. 6010

#64 and #45 TEST FIXTURES - Close-up comparison.

#64 TEST FIXTURE -Perform Guard EPS and

R-Control Do-All-Ply.

#45 Test Fixture -Non-Treated EPS and

standard constructionadhesives.

TECH BULLETIN

Subject:

Date:

Perform Guard No.





6011

Foam-Control EPS with Perform Guard and Building Code Compliance

January 2008

Foam-Control EPS with Perform Guard termite resistant ex-

panded polystyrene (EPS) is recognized in Foam-Control

building code evaluation reports for below grade applica-

tions in regions of very heavy termite pressure. This bulletin

provides a description of the testing required by the Interna-

tional Code Council Evaluation Service (ICC ES) to achieve

this recognition.

The ICC ES requirements to recognize a foam plastic insula-

tion as termite resistant are detailed in the “EVALUATION

GUIDELINE FOR TERMITE-RESISTANT FOAM PLASTICS,”

also known as EG 239. A summary of the testing require-

ments of EG239 are as follows:

• Testing shall be in accordance with AWPA E-7, “Standard

Method of Evaluating Wood Preservatives by Field Tests with

Stakes”, modified to suit the intended application of the ter-

mite-resistant foam plastic.

• Testing shall be representative of the final installed product.

• Test assemblies shall be exposed to a minimum of three ter-

mite test plots.

• Minimum of five replicates for each assembly type per test plot.

• Assemblies shall be arranged in a randomized complete

block design within the plots.

The assemblies are inspected annually along with wood

monitoring stakes to ensure that the plots are providing suf-

ficient and uniform exposure to termites. After 36 months

of exposure, the test assemblies are destructively evaluated

for termite damage. After the 36 months of exposure, the

termite-resistant foam plastic shall have no more than 5 per-

cent damage. Control or non treated samples shall also be

evaluated to confirm termite damage.

The development of EG239 was in response to language in

the model codes. For example, Section 320.5 of the 2006

International Residential Code (IRC) states: “ In areas where

the probability of termite infestation is “very heavy” … ex-

truded and expanded polystyrene, polyisocyanurate and

other foam plastics shall not be installed on the exterior face

or under interior or exterior foundation walls or slab founda-

tion located below grade.”

Thus, the use of foam plastics is restricted from use in ar-

eas of “very heavy” termite exposure. However, included in

the IRC is language for exceptions to the restriction. Spe-

cifically, exception 2 states that: “When in addition to the

requirements of R320.1, an approved method of protecting

the foam plastic and structure from subterranean termite

damage is provided.”

Foam-Control EPS with Perform Guard has been evaluated

by the ICC ES in accordance with EG239 under exception 2

of section R320.1 of the IRC. As a result, Foam-Control EPS

with Perform Guard has been recognized in the AFM evalu-

ation report, ESR-1006. ESR-1006 section 4.5 provides for

the special use of Foam-Control EPS with Perform Guard in

wood construction is areas of very heavy termite infestation.

The evaluation report language of section 4.5 is “Foam-Con-

trol EPS with Perform Guard® boards are termite-resistant

and are not restricted under Section R320.5 of the IRC or

Section 2603.8 of the IBC.”

Subsequently, Foam-Control EPS with Perform Guard may

be used in regions of “very heavy” termite exposure.

The Foam-Control EPS with Perform Guard treatment is for

the protection of the insulation integrity and does not pro-

vide protection for the structure. A pest control operator

should be contacted for protection of the structure in ac-

cordance with the IRC or IBC. Methods of protection may

be chemical soil treatment, pressure preservatively treated

wood, naturally termite resistant wood, physical barriers, or

any combination of these methods.

TECH BULLETIN

Subject:

Date:

Perform Guard No.





6012

Foam-Control developed a full scale research program in

the 1990’s to determine the effectiveness of Foam-Control

EPS with Perform Guard when exposed to termites.

Some historical research had been previously conducted on

foam plastic insulation but these were small scale laboratory

tests and could not be anticipated to match performance in

real world applications. Small scale laboratory tests do not

replicate the below grade installation geometry of insulation

nor do they typically provide the necessary time exposure

of field installations.

Other research has also been published on borate treated

expanded polystyrene, but these are either at dosage lev-

els not commensurate with Foam-Control EPS with Perform

Guard or do not meet the requirements of the International

Code Council Evaluation Service (ICC ES) for termite resis-

tant foam plastics (Evaluation Guide 239). The requirements

of the ICC ES evaluation guide include:

• Testing shall be conducted for at least 3 years

• Testing shall be in accordance with AWPA E-7, “Stan-

dard Method of Evaluating Wood Preservatives by Field

Tests with Stakes”, modified to suit the intended appli-

cation of the termite resistant foam plastic.

• Testing shall be representative of the final installed

product.

• Test assemblies shall be exposed to a minimum of

three termite test plots.

• Minimum of five replicates for each assembly type

per test plot.

Based upon these requirements, the Foam-Control pro-

gram was developed to ensure that the test data was not

limited to a laboratory testing, but instead a full scale test

program of samples installed in heavy termite regions of the

U.S. Foam-Control contracted with a third party researcher

to conduct the testing. The testing consisted of evaluating

Foam-Control EPS with Perform Guard at three test sites.

One test site was located in the USDA research forest in

Athens, Georgia. Two additional test sites were located near

Gulfport, MS. At each test site, a minimum of 10 samples

of Foam-Control EPS with Perform Guard were evaluated.

Foam-Control worked to ensure that the testing fully com-

plied with ICC ES Evaluation Guide 239.

Upon completion of the test program, Foam-Control sub-

mitted the complete test data to ICC ES for evaluation.

ICC ES has subsequently published Evaluation Service Re-

port (ESR) number ESR-1006 which includes recognition of

Foam-Control EPS with Perform Guard as a termite resistant

insulation.

A summary of the third party research data from the Foam-

Control program was submitted to the peer reviewed Forest

Products Journal for publication. The paper met the strin-

gent requirements of peer review and has been published in

the March 2005 issue of the Forest Products Journal. A copy

of the article is attached to this technical bulletin.

The attached test were conducted under severe exposure

conditions that are intended to exceed actual exposure con-

ditions. Regardless of application area, Foam-Control EPS

with Perform Guard should be installed following the Foam-

Control EPS with Perform Guard below grade Application

Guide.

Foam-Control EPS - Termite Resistance Testing Update

January 2008

Boron-treated expanded polystyreneinsulation resists native subterranean

termite damage after 3-year field exposure

Lonnie H. Williams�

Todd B. Bergstrom

In 1992, the Model Energy Code be-gan to mandate use of insulation on andbeneath building foundations to enhanceenergy savings (CABO 1992). This useof insulation soon became commonplacein the southeastern United States, whichis a high-risk region for subterranean ter-mite attack. This led to a rise in termitedamage related to the use of insulation(Smith and Zungoli 1995a,1995b). TheNational Pest Management Associationwarned its member companies to regardall untreated insulation the same as un-treated wood in contact with the ground(Kramer 1993).

Termites can tunnel through insula-tion and/or the interface between insula-tion and the foundation. Insulation en-closing entire masonry or concrete foun-dations (below ground and covered bycoatings such as synthetic stucco) pro-

vides termite entryways that cannot bedetected by inspection. Therefore, per-sonnel with responsibility for effectivetermite protection in many states pro-vide guidelines that require a 6-inch(150-mm) wide gap (inspection band)in insulation around the perimeter offoundations and have restricted its usebelow ground.

This study evaluates expanded poly-styrene (EPS) rigid foam insulation in-stalled in conjunction with constructionsealant (CS). Combinations of borate-treated EPS and CS were evaluated along

with untreated materials (Table 1). Theborate-treated EPS is manufactured un-der a patented process (Savoy 1993) us-ing disodium octaborate tetrahydrate(DOT). The product is marketed underthe brand name Perform Guard®.

Although small-scale laboratory ex-periments may be suitable for evaluatingcontact pesticides, a field test methodwas developed to evaluate the perfor-mance of a borate treatment chemical.Borate chemicals are slow-acting toxi-cants and limited initial damage was ex-pected to occur due to preliminary ter-mite exploration. Small-scale laboratorytests were not anticipated to be reliablepredictors of the field performance ofborate-treated EPS. Test units were de-signed that simulated use of rigid boardinsulation and CS around building foun-dations. Testing procedures were mod-eled after the American Wood Preservers’Association Standard E7-93 for evaluat-ing candidate wood preservatives byfield tests (AWPA 2000).

This paper describes the termite dam-age following 3 years of field exposureof untreated and treated EPS test unitsand the results of digital image analysesof EPS samples after in-ground expo-sure to termite attack.

56 MARCH 2005

The authors are, respectively, President, Rich Mountain Wood Protection Services, Inc.,14936 Angela Dr., Gulfport, MS 39503; and Technical Director, AFM Corp., 211 River RidgeCircle, #102, Burnsville, MN 55337. This paper was received for publication in September2003. Article No. 9747.�Forest Products Society Member.©Forest Products Society 2005.

Forest Prod. J. 55(3):56-60.

AbstractFoam plastic insulation around or beneath building foundations can provide hidden

entryways that must be considered for effective termite prevention. Borate-treated ex-panded polystyrene (EPS) rigid foam insulation installed with construction sealant(CS) to a concrete block was evaluated for resistance to damage by native subterraneantermites. The evaluation included 3-year exposure to termite attack in three widely sep-arated test plots of insulation-enclosed concrete test units partially buried in soil, withuntreated wood above and below the units to attract termites. By digital image analyses,the percentage of termite damage was quantified by treatment for field-exposed EPSsamples to provide data amenable to statistical analyses. Borate-treated EPS with bo-rate-treated CS had 3.2 percent damage compared to 23.9 percent for untreated EPS in-stalled with untreated CS after 3-year field exposure.

Materials and methods

Field tests

Treatments. — Test treatment combi-nations were: 1) EPS insulation boardbonded to concrete with constructionsealant (CS); 2) EPS insulation bonded toconcrete with DOT-treated CS; 3) DOT-treated EPS insulation, as AFM Corpora-tion’s Perform Guard®, bonded to con-crete with DOT-treated CS; and 4) DOT-treated EPS insulation bonded to con-crete with untreated CS. All insulationwas 2 inches (50 mm) thick.

Test units. — A test unit was a solidconcrete cap block with 12 inches (300mm) of EPS bonded flush with one endof the block on all four surfaces by acontinuous layer of either treated or un-treated CS. Figure 1 shows the compo-nents and how a unit was installed. In-stallation was completed by an opaqueplastic cover that provided protectionfrom weather and the dark conditionsthat termites prefer for tunneling activi-ties. A 3/8-inch- (10-mm-) diameter holein each narrow face provided ventilationto reduce condensate moisture. A south-ern pine sapwood stake, 3/4 by 1-1/2 by

18 inches long (19 by 38 by 460 mm),was driven in the ground to half its lengthadjacent to each unit for monitoring ter-mite activity during testing.

Untreated wood was placed under-ground as an attractant for termites asmay occur from buried wood at build-ing sites. The aboveground baitwoodcould be attacked only via tubes builtover or through insulation or the insula-tion/sealant interface. This test designsimulated what termites must do to at-tack wood in buildings above solid con-crete foundation walls insulated withrigid board insulation.

Test plots. — Ten replicates of eachtreatment were tested in each of threewidely geographically separated plots toensure exposure to different colonies andpopulations of termites. To offset thepossibility that the boron treatments mayaffect termite populations like a toxicbait, all test units were randomly as-signed to evenly spaced points on a gridconsisting of five columns and eightrows, with 10-foot (3-m) spacing be-tween points. Plots 1 and 2 were locatedin southern Mississippi, Harrison Countyand Stone County, respectively. Plot 3was located on University of Georgia Ex-periment Station property near Griffin,Georgia.

Annual inspection procedures. — Dur-ing the fall of 1995 through 1997, eachmonitoring stake adjacent to the test unitwas pulled and visually graded for ter-mite damage. Grading was done essen-tially as described by the American WoodPreservers’ Association Standard E7-93(2000) wherein a grade of 10 meant nodamage ranging through moderate dam-age at grades 7 or 6 to severe damage at4 and failure at 0. Stakes graded below 9for termite attack and stakes with exten-sive decay, but no termite attack were re-placed at each inspection.

Termite attack to the baitwood abovethe test units was graded by the samesystem. Each baitwood piece graded be-low 10 was replaced by a new piece.Ways that termites constructed tubes toreach the baitwood were recorded, suchas over the exterior or through insulationor at the insulation/sealant interface. Tun-nel openings (holes) in each unit’s topsurfaces were counted. These counts sug-gested that untreated insulation had se-vere, continuing damage. Termites alsomade initial explorations into treatedunits, but this activity did not appear to becontinuing. Digital image analysis of the

FOREST PRODUCTS JOURNAL Vol. 55, No. 3 57

Table 1.—Results of analysis of variance tests for annual inspection data by plot andyear.

Plot no. Variable Year Sig.a p-valueMeans comparison test

differences (LSD)b

1 Stake 1997 No p ≤ 0.1795 Treatment 1 with 2

1 Baitwood 1997 No

1 Hole counts 1997 No

2 Stake 1997 No

2 Baitwood 1997 Yes p ≤ 0.0001 Treatment 1 with 2, 3, 4

2 Hole counts 1997 Yes p ≤ 0.0001 Treatment 1 with 2, 3, 4

3 Stake 1997 No

3 Baitwood 1997 Yes p ≤ 0.0340 Treatment 1 with 2, 3

3 Hole counts 1997 Yes p ≤ 0.0007 Treatment 1 with 2, 3, 4a Yes means significant differences exist, no means they do not.b Treatments: 1 = untreated EPS/untreated CS; 2 = untreated EPS/treated CS; 3 = treated EPS/treated CS; 4

= treated EPS/untreated CS.

Figure 1.—Schematic showing construction and installation details of test unit usedto field test rigid foam insulation with untreated aboveground and below-groundbaitwood pieces to attract termites. Each insulation piece was bonded to concrete orinsulationwithacontinuous layerof untreatedorborate-treatedconstructionsealant.

interior of the insulation was chosen as amethod to quantify differences in termitedamage by treatment and to provide dataamenable to statistical analyses.

Digital image analysesSelection of sampled units. — After

the 1997 fall inspection, the five mostheavily damaged units/treatment wereselected, based on hole counts and bait-wood ratings from the 1995-1996 inspec-tions (20 units/plot, total 60 units).

EPS sampling procedures. — Sam-ples of EPS were cut with a hot-wire cut-ter. First, a cut was made through eachEPS piece to the concrete about 3 inches(75 mm) below the top surface of the testunit. EPS was cut at approximately 1/2-inch (12 mm) from the concrete becauseCS and soil-filled termite tunnels in un-treated EPS prevented cutting any closerto the concrete. Twelve surfaces were la-beled per unit: cross section of EPS 3inches (75 mm) below top surface, topinside surface, and bottom inside forEPS removed from the north side of theunit and the same sequence of samplesfor the east, south, and west surfaces.The total number of EPS surfaces sub-jected to analyses was: 12 samples/unit× 5 units/treatment = 60 EPS surfaces/treatment × 4 treatments = 240/plot × 3plots = 720 images after 3 years of fieldexposure.

Image archiving. — Hardware andsoftware used for archiving images in-cluded: Kodak DC-120 Digital Science®

camera equipped with PictureworksPhotoEnhancer® (PPE) image process-ing software, Media Cybernetic’s Im-age-Pro Plus® (IPP) image analysis andImage Database (IDB) software, and astaging platform and background illu-minated by incandescent bulbs in reflec-tor-type sockets. Each image was crop-ped to remove the EPS/background inter-face that was predetermined to interferewith analysis and archived in TIF formatvia the Twain-compliant features of theIPP and PPE software. All images werephotographed at the same focal distance.

Image analysis. — Each image wasanalyzed using the Hue-Saturation-In-tensity color model and pseudo-colorfeatures of the IPP software. First, an in-tensity channel was extracted from theimage and subjected to best-fit contrastenhancement. The enhanced image wasthen analyzed for its intensity contentand allocated to 1 of 2 predeterminedranges: 0 to 110 which indicated ter-mite-damaged EPS or 111 to 255 whichindicated undamaged (sound) EPS. TheIPP software calculated the area withineach range and the percentage of the to-tal image area that was either termite-damaged or sound. Before analysis, eachcropped image was examined visually toassess whether damage was from ter-mites or an apparent damage artifact re-sulting from CS and/or identification la-bels, which could not be automaticallydistinguished from termite damage.

Image analysis data. — The signifi-cance of treatment was determined byanalysis of variance (ANOVA) tests per-formed separately by plot on percent ter-mite damage data after arc sine transfor-mation. The presence of significant dif-ferences was determined by Fishers Mul-tiple Comparison tests.

Results and discussion

Field testsResults of ANOVA tests with corre-

sponding p-values show, by plot, whensignificantly different treatment effectsoccurred for stake or baitwood ratingsand hole counts (Table 1). The results ofmeans comparison tests show what treat-ments differed significantly from others.Mean stake ratings did not differ signifi-cantly by treatment for any plot. Thisimplies that all treatments were sub-jected to relatively uniform termite ac-tivity during field exposure.

Results for all plots suggested thattermite attack to wood above untreatedEPS increased with time while attacksto wood above other treatments remain-ed stable. Analyses of inspection datashowed that wood above units with un-treated EPS and untreated CS had sig-nificantly more damage than woodabove units with borate-treated EPS andborate-treated CS. In general, treatedEPS and treated CS offered the bestprotection.

Termites had also damaged boron-treated EPS and baitwood above it. At-tack of baitwood above treated units ap-parently was declining with time whileattack of baitwood above the untreatedcontrol was either increasing or was thegreatest attack. Inspection data, however,did not reveal how much treated EPSwas damaged nor how damage to EPSdiffered among treatments.

Image analyses offered a way of quan-tifying differences for statistical analy-ses to determine the effect of the treat-ments.

Image analysisCharacteristics. — For 720 analyzed

images, 375 had visible termite damage,345 did not. Estimates of damage in-cluding apparent damage from CSand/or identification labels for the 375samples ranged from 11.6 to 24.3 per-cent, by plot (Fig. 2). For the 345 imageswithout visible termite damage, the mean(± standard deviation) estimated damagewas 4.8 ± 1.8 percent. This error factor

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Figure 2. — Mean percent sound and damaged expanded polystyrene in sampleswith and without visible termite damage from each of three plots when images wereanalyzed following 3 years of field exposure.

associated with image analyses was es-sentially the same for each plot (Fig. 2).

Results. — In all three plots, results ofANOVA tests indicated that treatmentwas a highly significant factor (p ≤0.001) affecting the percentage of ter-mite damage in EPS. Results of MultipleComparison Tests (Fishers) indicatedthat the EPS for treatment 1 (untreatedEPS and untreated CS) had significantlygreater (p ≤ 0.05) termite damage thanEPS for the remaining treatments.

Analysis was conducted to comparethe damage to the top part of sampleswith that in the lower or bottom part ofthe sample. Damage to the top regionwould indicate significant tunnelingthroughout the EPS. Mean percentagesof damage for all plots were alwayshigher for bottom samples than top sam-ples for all treatments (Fig. 3). This wastrue across all plots and in each plot. Foruntreated EPS and untreated CS, dam-age was 30.2 percent for top samplesand 27.4 percent for bottom samples.However, damage was 0.9 percent fortop samples and 4.4 percent for bottomsamples from units with treated EPS andtreated CS, indicating that termites wereonly making exploratory attacks at thebottom of treated EPS pieces adjacent tothe large underground baitwood. When

only EPS or CS was treated, damage totop samples was from 8.0 to 10.0 per-cent and damage to bottom samples wasfrom 1.8 to 5.9 percent (Fig. 3).

When cross-section samples were in-cluded and the error factor adjustmentwas made, the mean percentage of EPSdamaged by termites was 3.2 percent forborate-treated EPS and borate-treatedCS but 23.9 percent for samples withuntreated EPS and CS. Means of termitedamage for the remaining two treatmentswere 3.9 and 5.4 percent. Exposing insu-lation on all sides of a unit 4 inches (100mm) below the groundline and just 2inches (50 mm) above 179.5 in.3 (2942cm3) of untreated wood obviously wasvery severe exposure to subterranean ter-mite attack (Fig. 1). Nevertheless, dam-age to borate-treated EPS with borate-treated CS remained a relatively minor3.2 percent. A damage level of under 5percent is considered acceptable by theInternational Code Council evaluationguideline for foam plastic insulation(ICC 2003).

Conclusions

Annual inspection dataStake ratings did not differ signifi-

cantly by treatment for any plot or year,which implies that all treatments were

subjected to uniform termite activity.Wood above test units with untreatedEPS and untreated CS showed signifi-cantly greater damage than wood aboveunits with one of the three other treat-ments. Damage to the top surfaces ofEPS with untreated EPS and untreatedCS showed significantly greater dam-age than EPS surfaces on units with oneof the other treatments. Results suggestthat termite damage to EPS and/or un-treated wood above it can be reduced byDOT treatment of EPS insulation andCS.

Image analysis dataThe EPS on test units with untreated

EPS and untreated CS had significantly(p 0.01) greater damage from termitesthan the EPS on units with the otherthree test treatments containing combi-nations of borate-treated EPS and/or CS.EPS protected by the treatment combi-nation of borate-treated EPS and bo-rate-treated CS sustained less termitedamage than EPS protected only bytreated EPS or treated CS. Image analy-ses offer a reasonably accurate proce-dure for quantifying termite damage inEPS. Termites caused 3.2 percent dam-age when EPS was protected by borate-treated EPS and borate-treated CS com-pared to 23.9 percent for EPS not pro-tected by any treatment.

Borate-treated wood is known to be aslow-acting toxicant, allowing termitesto cause minor damage to wood beforethey either are killed or stop their at-tacks. Unlike wood, EPS apparently pro-vides no food value, but potential shel-ter for termites. However, boron must beingested as termites tunnel through orbuild tubes over EPS or damage wouldnot be deterred. Unlike previous small-scale laboratory testing, field testingconfirmed that borate treatment of EPSoffers good protection against termitedamage.

Literature citedAmerican Wood Preservers’ Association

(AWPA). 2000. Standard method of testingwood preservatives by field tests with stakes.Standard E7-93. In: 2000 Book of Standards.AWPA, Granbury, TX. 12pp.

Council of American Building Officials(CABO). 1992. Model energy code. CABO,Leesburg, VA. 87 pp.

Kramer, R.D. 1993. Foam insulation and ter-mites. Service Letter ESPC 055075, No. 1284.National Pest Control Assoc., Inc., DunnLoring, VA. 3 pp.

International Code Council (ICC). 2003. Evalu-ation guideline for termite-resistant foamplastics, EG239. ICC, Whittier, CA. 3 pp.

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Figure 3.—Mean percentages of termite-damaged insulation per treatment for bot-tom and top samples of units in all plots after 3 years of field exposure (n = 60).Means shown are after subtraction of an error factor associated with image analy-ses of 2.7 for bottom and 3.4 for top samples: n for error factors = 28 and 145,respectively.

Savoy, T.L. 1993. Building material with pro-tection from insects, molds, and fungi. U.S.Patent No. 5,194,323. U.S. Patent and Trade-mark Office, Washington, DC. 12 pp.

Smith, B.C. and P.A. Zungoli. 1995a. Termitesin rigid board insulation: Part 1. Pest ControlTechnol. 23(10):68,69,72-74.

__________ and __________. 1995b. Termitesin rigid board insulation: Part 2. Pest ControlTechnol. 23(11):56,65-66.

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