Bill Gorton Report

There is more than 2% difference between moisture content at the top of boards, and the subfloor. As noted above, by measuring the trowel marks the inspector was able to determine that the installer failed to use a ¼ x ¼ trowel as required by the adhesive manufacturer. The installer used an improper trowel, according to the manufacturer's instructions, as well as applied an insufficient amount of adhesive. Failure to use the proper trowel, and failure to apply the adhesive according to manufacturer guidelines will lead to moisture issues in wood flooring. From the manufacturer’s guidelines: Use DriTac 7300 adhesive with a properly notched trowel. All square footage rates are estimated. Rates will vary based on substrate condition and the angle the trowel is held to the subfloor. Failure to properly flatten the subfloor may result in hollow spots. DriTac warranties do not cover problems caused by improper use of installation products. 5/16” Solid Parquet, 1/4” TR-5 80 sq. feet/gal. Engineered Plank, 1/8” x 1/8” x 1/8” Square Approved Cork/Rubber/Foam Underlayment, Recycled Notch Rubber Flooring Over Porous Substrates See: DriTac 7300 Technical Data Sheet attached as Exhibit B. Inspector notes that the spider-webbed type of foaming pattern observed under boards (see Photo Nos. 33-34) is usually only seen when there is an issue with flatness. The foaming pattern has clearly overtaken most of the trowel pattern marks. This is because of the up and down motion while the glue was curing because the floor is out of flat. Additionally, this sort of bubbling is sometimes indicative of high moisture content. Sanding and Finish Issues This inspector was advised that homeowner, commissioning party, and the installer agreed that installer would complete the installation in the downstairs kitchen. Based upon this inspector’s observations, the floor installed in this kitchen fails to meet NWFA guidelines. Bill Gorton – Photo Narrative regarding 5510 Fulton Ave, Los Angeles, CA 91401 Page 51 of 56

Buffer marks are visible from a standing height under normal lighting. Inspector observed start and stop marks. Drum marks. Some amount of edger marks as well. See Photo Nos. 36-43. This wouldn’t be considered an acceptable job. This would be unacceptable across the entire room. Additionally, the inspector notes that, downstairs, the flooring product is a solid hardwood flooring product. In the basement, the installer has apparently unilaterally elected to install micro-beveled, engineered flooring rather than the square-edge product that was specified and agreed to. This produces undesirable and unsightly lines that are incompatible with the desired aesthetic produced by the downstairs flooring. See Photo Nos. 44-45. After some investigation, this Inspector was informed that neither homeowner nor contractor requested disparate wood flooring be installed at this site. Both homeowner and contractor expected that solid hardwood would be used throughout the entirety of the installation. CONCLUSION The preceding data, the on-site inspection, and the interviews with the involved parties support the following conclusion: Please call if you have any questions or require any further information, regarding this report. Sincerely, ___________________________________________ _________________________ Jeffrey B. Meltzer Date NWFA Certified Flooring Inspector, CR License # CP1980205 Phone: 310-839-9663 Email: [email protected] President Flooring Detective Bill Gorton – Photo Narrative regarding 5510 Fulton Ave, Los Angeles, CA 91401 Page 52 of 56

LIST OF EXHIBITS Exhibit “A” - NWFA Section II Subfloor Guidelines and Specifications Exhibit “B” - DriTac 7300 Technical Data Sheet Exhibit “C” - National Wood Flooring Association Installation Guidelines Wood Flooring – Chapter 3: “Solid Parquet Floor”

EXHIBIT “A” NWFA Section II Subfloor Guidelines and Specifications

Section II Subfloor Guidelines & Specifications Chapter 4 Wood Subfloor Guidelines Page Chapter 5 Concrete Subfloor Guidelines 23 Chapter 6 Installing a Subfloor Over Concrete 26 27 24 National Wood Flooring Association ©2007 l Revised 02.2016

Chapter 4 Wood Subfloor Guidelines Note: Always follow the wood flooring manufacturer’s recommendation for a proper subfloor. Part I Wood Subfloor Specifications A. Subfloor panels should conform to U.S. Voluntary Product Standard PS1-07, Construction and Industrial Plywood and/or US Voluntary PS 2-04 and/or Canadian performance standard CAN/CSA 0325.0-92 Construction Sheathing. Other CSA standards also apply. B. Solid-board subflooring should be ¾” x 5½” (1” x 6” nominal), Group 1 dense softwoods, No. 2 Common, kiln- dried to less than 15 percent moisture content. C. Both CD Exposure 1 plywood and OSB Exposure 1 subfloor panels are appropriate subflooring materials, but the proper thickness of the material will be determined by the factors noted below in Part IV, Panel Products Subflooring, E, Acceptable Panel Subfloors. Part II Subfloor Moisture Note: The National Association of Home Builders’ Green Home Building Guidelines contain the following directive under Section 5.3.8: “NAHB Model Green Home Building Guidelines, Section 5.3.8: Check moisture content of wood flooring before enclosing on both sides. Ensure moisture content of subfloor/substrate meets the appropriate industry standard for the flooring material to be installed.” A. For solid strip flooring (less than 3” wide), there should be no more than 4 percent moisture content difference between properly acclimated wood flooring and subflooring materials. B. For wide-width solid flooring (3” or wider), there should be no more than 2 percent difference in moisture content between properly acclimated wood flooring and subflooring materials. Part III Subfloor Flatness and Integrity A. Wood subfloors must be flat, clean, dry, structurally sound, free of squeaks and free of protruding fasteners. 1. For installations using mechanical fasteners of 1½” and longer, the subfloor should be flat to within ¼” in 10 feet or 3/16” in 6 feet radius. 2. For glue-down installations and installations using mechanical fasteners of less than 1½”, the subfloor should be flat to within 3/16” in 10 feet or 1/8” in 6 feet radius. B. If peaks or valleys in the subfloor exceed the tolerances specified above, sand down the high spots and fill the low spots with a leveling compound or other material approved for use under wood flooring. However, it is the builder’s or general contractor’s responsibility to provide the wood-flooring contractor with a subfloor that is within the tolerances listed above. When possible, check the back of the subfloor panel for American Plywood Association (APA) rating. 25 National Wood Flooring Association ©2007 l Revised 02.2016

C. Inspect the subfloor carefully. If there is movement or squeaks in the subfloor, refasten the subfloor to the joists in problem areas. D. Protruding fasteners are easily remedied by driving those fasteners deeper into the subfloor. Part IV Panel Products Subflooring A. For panel products subflooring, check for loose panels and renail or screw down loose panels securely. B. Ensure that there is proper expansion space (1/8”) between the panels. If the subfloor panels are not tongue- and-grooved and if there is not sufficient expansion space, use a circular saw to create the specified space. Do not saw through joints on T&G subfloors. C. Also check for delaminated or damaged areas and repair those areas as needed. D. Make sure the subfloor is free of debris before beginning installation. E. Acceptable Panel Subfloors: Truss/joist spacing will determine the minimum acceptable thickness of the panel subflooring. 1. On truss/joist spacing of 16” (406mm) o/c or less, the industry standard for single-panel subflooring is minimum 5/8” (19/32”, 15.1mm) CD Exposure 1 Plywood subfloor panels (CD Exposure 1) or 23/32 OSB Exposure 1 subfloor panels, 4’ x 8' sheets. 2. On truss/joist spacing of more than 16”, up to 19.2\" (488mm) o/c, the standard is minimum ¾” (23/32”, 18.3mm) T&G CD Exposure 1 Plywood subfloor panels, (Exposure 1), 4’ x 8' sheets, glued and mechanically fastened, or minimum ¾” (23/32\", 18.3mm) OSB Exposure 1 subfloor panels, 4’ x 8’ sheets, glued and mechanically fastened. When possible, check the back of the subfloor panel for American Plywood Association (APA) rating. 3. Truss/joist systems spaced over more than 19.2” (488mm) o/c up to a maximum of 24” (610mm) require minimum 7/8” T&G CD Exposure 1 Plywood subfloor panels, (Exposure 1), 4’ x 8' sheets, glued and mechanically fastened, or minimum 7/8” OSB Exposure 1 subfloor panels, 4’ x 8’ sheets, glued and mechanically fastened – or two layers of subflooring. Or brace between truss/joists in accordance with the truss/joist manufacturer’s recommendations and with local building codes. Some truss/joist systems cannot be cross-braced and still maintain stability. a. For double-layer subfloors, the first layer should consist of nominal ¾” (23/32”, 18.3mm) CD Exposure 1 Plywood subfloor panels (CDX), 4’ x 8' sheets or nominal ¾” (23/32”, 18.3mm) OSB Exposure 1 subfloor panels, 4’ x 8’ sheets. The second layer should consist of nominal ½” (15/32”, 11.9mm) CD Exposure 1 plywood subfloor panels, (Exposure 1) 4’ x 8’ sheets. The ½” plywood should be offset by ½ panels in each direction to the existing subflooring. The panels may also be laid on a diagonal or perpendicular, with 1/8” spacing between sheets. Nail on a 12” minimum grid pattern, using ring- shanked nails or staples. F. Fastening and Spacing Specifications 1. Follow the panel manufacturer’s recommendations for spacing and fastening. 2. Typical panel spacing and fastening requirements for truss/joist systems call for approximately 1/8” (3.2mm) expansion space around the perimeter of each panel, with panels fastened every 12” (305 mm) along intermediate supports. 3. Edge swell should also be flattened. This can usually be accomplished by using an edger sander. Part V Solid Board Subflooring A. Solid board subflooring should be: ¾” x 5½” (1” x 6”), Group 1 dense softwoods (SYP, Doug Fir, Larch, etc.), No. 2 Common, kiln-dried to less than 15% MC. Refer to Chapter 2, Acclimation and Conditioning of Wood Flooring, for proper subfloor moisture content at time of installation. B. Solid board subflooring should consist of boards no wider than 6 inches, installed on a 45-degree angle, with all board ends full bearing on the joists and fastened with minimum 8d rosin-coated or ring-shanked nails, or equivalent. C. Some types of wood flooring should not be installed directly over solid board subflooring. 1. Thin-classification solid strip flooring must have a 3/8”or better plywood underlayment installed over solid board subflooring. 26 National Wood Flooring Association ©2007 l Revised 02.2016

2. Parquet flooring cannot be installed directly to solid board subfloors. A parquet installation over solid board subflooring requires 3/8” or better underlayment panels, nailed on 6” minimum grid pattern using ring-shanked nails or staples. D. Some engineered flooring cannot be installed directly to solid board subfloors. (See wood flooring manufacturer’s recommendations.) 27 National Wood Flooring Association ©2007 l Revised 02.2016

Chapter 5 Concrete Subfloor Guidelines Note: Always follow the wood flooring and adhesive manufacturer’s recommendation for a proper subfloor. Part I Concrete Subfloor Specifications A. Subfloor must be flat. 1. Make sure the concrete slab is flat to the wood flooring manufacturer’s specification. Typically, manufacturers will specify a flatness tolerance of 1/8”in a 6-foot radius and or 3/16” in a 10-foot radius. 2. If the slab is out of specification, consider grinding, floating or both. Many high spots can be removed by grinding, depressions can be filled with approved patching compounds, and slabs also can be flattened using a self-leveling concrete product. 3. When sanding or grinding concrete, care must be taken to minimize the amount of silica dust produced. OSHA recommends using dust-collection devices, or applying water to the concrete before sanding. Approved respirators may also be used to minimize the amount of silica dust inhaled. B. Subfloor must be dry. 1. See Chapter 3, Moisture Guideline Testing and Vapor Retarders. 2. Concrete moisture meters and other tests can be useful in identifying moisture problem areas. However, NWFA guidelines specify using relative-humidity testing (ASTM F2170), calcium chloride testing (ASTM F1869) or calcium carbide (CM) testing (ASTM D4944 and MilSpec CRD-C154-77) to identify the moisture content of the slab. See Chapter 3, Moisture Guideline and Vapor Retarders. 3. If a slab tests too high in vapor emission to glue a floor down, consider using a vapor retarder type product, installing a vapor retarder and a plywood subfloor or using an alternative installation method. 4. Concrete slabs with a calcium chloride reading of more than 3 require use of a vapor retarder with a perm rating of 1 or less. It is strongly recommended to use an impermeable vapor retarder with a perm rating of .13 or less, such as 6 mil polyethylene film. C. Slab must be: 1. Minimum 3000 psi. 2. Free from non-compatible sealers, waxes, oil, paint, drywall compound, etc. a. Check for the presence of sealers by applying drops of water to the slab. If the water beads up, there may be sealers or oils. D. Do not attempt to glue a wood floor over a chalky or soft concrete slab. E. Burnished or slick slabs may require screening or sanding with a 30-grit abrasive. F. Specifications for lightweight concrete: 1. Make sure the concrete is well bonded to the subfloor. Check for hollow spots, cracks and loose areas. 2. As with on-grade concrete subfloors, make sure the concrete is clean, flat to specification and dry. 3. Over lightweight concrete (less than 3000 psi), if the flooring adhesive used has a higher shear strength than the concrete, use the floated subfloor installation method. (See Chapter 6, Installing a Subfloor Over Concrete.) If the psi of the concrete is unknown, use the floated subfloor installation method or contact the adhesive manufacturer. 4. Rule of thumb: Draw a nail across the top; if it leaves an indentation, it is probably lightweight concrete. 28 National Wood Flooring Association ©2007 l Revised 02.2016

Chapter 6 Installing a Subfloor Over Concrete Note: Always follow the manufacturer’s recommendation for a proper subfloor. Part I Direct Gluing a Subfloor Over Concrete A. Always follow the adhesive manufacturer’s recommendation for proper application, proper adhesive and correct trowel notch and spread rate. B. If necessary, add vapor retarder recommended by the adhesive manufacturer before applying adhesive. Part II Floated Subfloor A. In on-grade and below-grade applications, always add vapor retarder before applying underlayment. B. In above-grade applications, follow the flooring manufacturer’s recommendations. C. A vapor retarder is recommended anytime solid ¾” wood flooring is installed over concrete. A vapor retarder is required for installation over concrete with a calcium chloride reading greater than 3 pounds, a relative humidity reading of greater than 75%, or a calcium carbide (CM) reading of greater than 2.5%. D. Floated Subfloor System 1. Materials a. 2 layers minimum 3/8” (10mm) minimum CD Exposure 1 Plywood subfloor panels (CDX) 4’ x 8' sheets. 2. Installation method a. Place the first plywood layer with edges parallel to wall, without fastening. Leave ¾” space between wall and plywood. b. Plywood panels should be placed with 1/8” gaps between sheets. c. Lay the second layer perpendicular or at 45 degree angle to the first. d. Plywood panels should be placed with 1/8” gaps between sheets and a ¾” minimum expansion space at all vertical obstructions and wall lines. e. Staple/screw and glue (with urethane or construction adhesive) the second layer to first layer on 12” interior grid pattern (6” on the perimeter). Be careful not to penetrate the vapor retarder. E. Alternate Subfloor System 1. Materials a. Use minimum ¾” (23/32”, 18.3mm) CD Exposure 1 Plywood sheathing, 4’ x 8’ sheets. 2. Installation method a. Cut sheets to 16” x 8’ or smaller panels, scored on back 3/8” deep a minimum of every 12” across width. b. 16” planks oriented perpendicular or diagonally to direction of flooring. c. Panels staggered every 2’, and spaced 1/8” between ends, with ¾” minimum expansion space at all vertical obstructions. Part III Glue-Down Subfloor A. Always follow the adhesive manufacturer’s recommendation for proper subfloor, spread rate and trowel notch. B. If necessary, add vapor retarder before applying underlayment. A vapor retarder is recommended anytime solid ¾” wood flooring is installed over concrete. C. Glue-Down Subfloor System: 1. Materials a. Use minimum ¾” (23/32, 18.3mm) CD Exposure 1 Plywood subfloor panels, (Exposure 1), 4’ x 8’ sheets. 2. Installation method a. Cut the plywood panels to 2’ x 8’ or 4’ x 4’ sections. 29 National Wood Flooring Association ©2007 l Revised 02.2016

b. Score the back of the panels ½ the thickness on a 12” x 12” grid. c. Apply an adhesive approved for the installation of plywood, per the plywood manufacturer’s recommendations. d. Lay sections in a staggered joint pattern in the adhesive, with 1/8” spacing between sheets, and ¾” minimum expansion space at walls and all vertical obstructions. Part IV Nail-Down Subfloor A. Always follow the manufacturer’s recommendation for proper subfloor. B. In on-grade and below-grade applications, always add vapor retarder before applying underlayment. In above- grade applications, follow the flooring manufacturer’s recommendations. C. A vapor retarder is recommended anytime solid ¾” wood flooring is installed over concrete. D. Nail-Down Subfloor System Over Concrete 1. Materials a. Minimum: Use minimum ¾” (23/32, 18.3mm) CD Exposure 1 Plywood subfloor panels (CDX), 4’ x 8’ sheets. 2. Installation method Note: Fasteners may be powder-driven pins, pneumatic driven nails, screws, deformed pins, or other fasteners suitable for concrete application. Check with fastener manufacturer for specification such as length, drill size, and/or shot load where applicable. a. Stagger panel joints allowing approximately 1/8” expansion space around all panels to prevent edge peaking due to compression caused by panel swell. b. Allow ¾” minimum expansion space at all vertical obstructions. c. Panels should be mechanically fastened. For powder load or pneumatic pressure information, contact your local supplier. d. Nailing requirements, minimum 32 shots per 4’ x 8’ panel. e. Areas with higher humidity may require additional fasteners. Part V Screed System A. Solid ¾”, 25/32” and 33/32” tongue-and-groove strip flooring may be installed directly to screeds. B. Engineered wood flooring less than ¾” (23/32”) thick, thin-classification strip flooring (including ½”) and solid plank flooring (3” or wider) cannot be installed directly to screeds. C. For engineered flooring less than ¾” thick, thin-classification strip, and for solid plank (3” and wider), the screed system must be overlaid with proper subflooring. The screed system must be overlaid with nominal ¾” (23/32”, 18.3mm) Exposure 1, or nominal 5/8” (19/32”, 15.1mm), Exposure 1, CDX plywood subfloor panels or nominal ¾” (23/32”, 18.3mm) OSB underlayment properly spaced and oriented perpendicular to screed direction. All joints must be staggered. D. Installation method. See Appendix I, Installation Over Screeds. 30 National Wood Flooring Association ©2007 l Revised 02.2016

EXHIBIT “B” DriTac 7300 Technical Data Sheet

7300 SUREBOND Urethane Wood Flooring Adhesive OWNED & OPERATED IN USA TECHNICAL DATA SHEET DriTac 7300 is a contractor grade, urethane wood flooring adhesive that is very easy to spread and dispense from the pail, allowing for increased productivity. It contains no water and provides a permanent bond. ATTRIBUTES • MVER up to 5 lbs./80% RH • Remains Elastomeric • Easy to Spread • Easy to Clean When Wet • Freeze-Thaw Stable • Helps Contribute to LEED Credits • Non-Slumping • Low Odor FLOORING TYPES • M ulti-Ply Engineered Plank • Solid Wood Planks • Parquet • Acrylic Impregnated Wood • Bamboo • R ecycled Rubber Flooring • Plywood • Exotic Woods AVAILABLE CONTAINER SIZE • 4-Gallon Pail • 2-Gallon Pail • 20 oz. Sausage

TECHNICAL DATA SHEET INSTRUCTIONS Read all information before installation. Please contact DriTac Flooring Products at (973) 614-9000 with questions. GENERAL CHARACTERISTICS DriTac 7300 has been formulated for the interior installation of multi-ply engineered plank, solid plank, bamboo, exotic wood, acrylic impregnated wood, parquet, plywood, recycled rubber flooring and cork and rubber underlayments over approved substrates. DriTac 7300 is moisture resistant, however, to prevent damage to the flooring from subfloor moisture, carefully follow the wood manufacturer’s instructions. The time it takes for the adhesive to cure is related to temperature, humidity, porosity of the subfloor, ventilation and air movement. APPROVED SUBFLOORS • Plywood • Terrazzo and ceramic tile • Underlayment grade O.S.B. • Vinyl tile flooring coated with vinyl primer • Concrete; above, on or below grade in the absence of excessive moisture and alkalinity • Non-cushioned fully adhered sheet vinyl coated with vinyl primer • Lightweight concrete/gypcrete (coated with latex primer), per ASTM F2419 Note: If DriTac’s list of approved subfloors is different from the flooring manufacturer, DriTac requires that you must follow the flooring manufacturer’s recommendation. SUBFLOOR REQUIREMENTS • Clean - It is required that all concrete, sheet vinyl, vinyl tile, terrazzo and ceramic tile subfloors be scoured with #3-1/2 open coat sandpaper to remove dirt or any surface contamination such as paint, grease, oil, sealers, waxes and curing compounds. DriTac 7300 adhesive should not be used over these substances. Sweep or vacuum the subfloor before installation. • Preparation - All floors should be flat to within 3/16” in 10 ft. or 1/8” in 6 ft. • Smooth and Flat - Remove any high spots with a terrazzo grinder or Carborundum stone and fill any low spots with a good quality cementitious-based latex patch mix. CONCRETE SUBFLOORS Concrete should be at least 60 days old. Inspect the concrete before installing flooring over it. First inspect for any wetness at the base of the drywall or for visible signs of moisture on the concrete. Second, test for moisture. Use a Calcium Chloride Method Test or Relative Humidity Test for reliable concrete testing. The results should not exceed 5 lbs., per 1,000 square feet over 24 hours, per the ASTM F1869 Calcium Chloride Method Test, or 80% Relative Humidity (RH), per the ASTM F2170 Relative Humidity Method Test. The maximum reading on concrete for wood installations should not exceed the wood flooring manufacturer’s recommendations. Many wood flooring products can be installed over lightweight concrete (less then 3000 PSI) or gypcrete, providing the surface is properly prepared. Follow the concrete manufacturer’s recommendation for the application of a surface hardener/sealer. Radiant heated subfloors should be turned off 24 hours prior to and during installation to prevent premature curing of the adhesive. SHEET VINYL, VINYL TILE, TERRAZZO & CERAMIC TILE SUBFLOORS All tiles or sheet goods must be firmly bonded to the subfloor. Make certain the sheet vinyl is a full spread system, perimeter installations are unacceptable. If materials are poorly bonded to the subfloor remove them down to the original subfloor and sand or scrape off all traces of old adhesive. Do not glue over heavy cushioned (1/4”) sheet goods or rubber tile. New sheet vinyl or vinyl tile must be coated with a primer. Old vinyl must be sanded first, then cleaned with TSP or equivalent cleaner to remove all wax and other coatings. CAUTION: Sanding or removing tile flooring containing asbestos is a health hazard. If there is any doubt concerning the contents, professional advice should be sought. Asbestos has been labeled a carcinogen. PLYWOOD, ORIENTED STRAND BOARD (OSB), OR WOOD SUBFLOORS CAUTION: Subfloors with high moisture content may shrink at a later date causing cracks to appear in the wood floor. Before installing over any one of these subfloors, test for moisture using a reliable moisture meter such as the Tramex Wood Moisture Meter or equivalent. The moisture content should not exceed 12%. If it is over 12%, either wait until the subfloor is drier or stabilize the subfloor with an additional layer of ¼” plywood. All joints in subflooring materials should have 1/8” expansion space around all panels. If expansion space is not present, cut around and through the panel joints with a circular saw. When installing a plywood sheet subfloor over concrete, use a ¼” x ¼” x ¼” square notched trowel to apply adhesive. Score 3/8” deep every 8 to 10 inches on 4’ x 4’ sheets of ¾” exterior. Set 4’ x 4’ sheets into wet adhesive. Apply weight as necessary and allow to cure overnight. WOOD INSTALLATIONS DriTac 7300 flows from the pail very easily. For best results, tip the pail carefully to dispense adhesive. Provide adequate ventilation and air movement. Ideally, installation should not begin until all wet work (painting, dry wall materials, etc.) is complete and the

TECHNICAL DATA SHEET heating/air conditioning system is in operation. Jobsite temperature should be between 55 and 90 degrees Fahrenheit. Trowel only the amount of adhesive that can be covered in 30 minutes. Install wood flooring into wet adhesive only. Secure the first row with edge blocking or top nail with finishing or sprig nails. Tighten side and end joints and reduce scooting by securing the flooring together with a manufacturer-approved method (painters tape, side blocking, strapping, etc.). Occasionally check for transfer to back of wood flooring. If adhesive transfer is less than 90% to the back of the plank scrape up the adhesive and apply fresh DriTac 7300. Apply weight to any bowed flooring and all floor mounted trim moldings. Remove all defective or unsightly boards immediately. The adhesive is very tenacious and flooring is difficult to remove after the adhesive has cured. Roll the floor with a 100 lb. roller every two to three hours during and immediately after installation. RECYCLED RUBBER FLOORING INSTALLATIONS This product is approved for installing all recycled rubber flooring products that are recommended for installation with a moisture cure urethane adhesive. Check with the flooring manufacturer for installation recommendations. APPROVED CORK & RUBBER UNDERLAYMENT INSTALLATIONS • Cut underlayment to length and lay loosely over the area to be installed. Both ends of the roll must curl down towards the subfloor. If the ends curl up, turn the underlayment over. • Pull the loose laid material back at least half the length of the roll. Using the recommended trowel, apply DriTac 7300 to the subfloor. Place underlayment into adhesive utilizing wet-lay method. Upon placing underlayment into the adhesive, roll both ways with a 100 lb roller. Repeat the installation for the other half of the subfloor, insuring all joints are butted together tightly. • Allow adhesive to set prior to proceeding to flooring installation. It is highly recommended to allow at least 18 hours prior to installation of the flooring. TR-1 TR-6 TR-11 GLUE/NAIL ASSIST INSTALLATIONS This adhesive can be used for glueTRa-1nd nail assisTtR-i6nstallationsT,R-w11hen recommended in writing by the wood flooring manufacturer. DriTac 7300 adhesive sausages areTR-a2vailable forTRg-l7ue assist inTsRt-1a2llations. TROWELS AND CTOR-2VERAGE TR-7 TR-12 Floor Type DriTacTTRRT--r31owel TTRR--86Coverage TR-13 TR-11 Multi-ply Engineered Plank TR3-/216- ”3x/1-16a/”4lsx”ox1kT/5TTn4R/RRo”1---6wo634n”nF1ala/s2t-”VCNeonttcehrs TR6-80 sq. feet/gal. TR-13 TR-11 3/8” up to 1/2” TR-1 TR-14 TR-9 TR-12 Multi-Ply Engineered Plank TR-2 TR-7 3/8” up to 1/2” (when TR-4 TR5-90 sq. feet/gal. TR-14 additional adhesive is required) TR-6 TR-12 TR-13 and 5/16” to 3/8” Solid StTrRip-2 3/16” x 5TT/R3R-2-75” V Notch TR-3 TR-10 TR-8 5/16” Solid Parquet, 1/4” TTRR--65 TRT-R1-110 Engineered Plank, ApprovTeRd-1 TTRR--85 TR-1830 sq. feet/gal. 1/8” x 1/8” x 1/T8R”-4Square Notch Cork/Rubber/Foam TR-3 TR-6 TR-9 TR-11 Underlayment, Recycled Rubber TR-14 Flooring Over Porous SubsTtRr-a1tes TR-1 TTTRRR--4-26 TTTRRR--1-971 TR-12 3/4” Solid Wood Plank/ 1/4” x 1/4” x 1TT/R4R-”-45Square Notch TR-14 Shorts, 4’ x 4’ Plywood TR-7 30 sq. feet/gal. TR-8 TR-2 TTRR--1120 TR-10 TR-12 GreateTrR-t2han 1/2” TR-3 TTRR--78 TR-13 TTRR-5-7 1/4” x 1/4” x 1T/R8-”9Square Notch Engineered Plank, TR-13 3/4” Parquet and Solid TR-3 TR-1335 sq. feet/gal. Plank greater than 3/8” TR-14 up to T9R/1-36” TR-4 TR-8 Bamboo up to 5/8” to TR-4 TR-9 TR-14 3/16” x 3/16” x T3TTRR/R1---19614”0Square Notch 35 sq. feet/gal. 9/16” TinR-t4hickness TTRR--59 Recycled Rubber FlooringTR-5 TR-10 100 sq. feet/gal. over Non-Porous Substrates TR-15 TR-5 TR-10 3/32” x 3/32” x 3/32” Square Notch Trowels diagrams are not to scale. Use DriTac 7300 adhesive with a properly notched trowel. All square footage rates are estimated. Rates will vary based on substrate condition and the angle the trowel is held to the subfloor. Failure to properly flatten the subfloor may result in hollow spots. DriTac warranties do not cover problems caused by improper use of installation products. Follow flooring manufacturer’s written installations instructions.

TECHNICAL DATA SHEET LIMITATIONS Adhesive will not prevent moisture-related damage to wood flooring installations. DriTac 7300 adhesive is affected by humidity more than temperature. High humidity will cause the adhesive to cure faster and low humidity will slow the curing process. Do not use on wet, contaminated or friable substrates. Due to dimensional stability, only engineered plank wood flooring can be installed below-grade, when proper moisture testing has been conducted and the results do not exceed limitations. After 8 to 12 hours, light traffic is allowed. Do not use as a leveling material. Cutback residue must be removed or encapsulated prior to applying adhesive. REUSE OF PARTIAL CONTAINERS Cover adhesive in the pail with a plastic trash bag or two layers of plastic film. Put lid on tightly. Turn over pail. This will seal contents from outside air. To open container, take off lid, cut plastic and remove thin layer of cured adhesive on surface. SHELF LIFE 12 months when stored at 75° F and 50% relative humidity. CLEAN UP • Remove excess urethane adhesive as soon as possible before it dries on the flooring surface. Clean up as you go. Cured urethane adhesive is very difficult to remove. • Never attempt to remove DriTac 7300 adhesive from tools or flooring with water as this will cause the adhesive to cure more rapidly. • Remove residue before it dries with DriTac Urethane Adhesive Remover or other flooring manufacturer-approved cleaning method. • Clean DriTac 7300 adhesive from floor and tools while still wet with DriTac Urethane Adhesive Remover or other flooring manufacturer-approved cleaning method. PRECAUTIONS • Contains Methylene Diphenyl Diisocyanate. May cause skin and/or eye irritation. May cause dermatitis and allergic responses. Potential skin and/or respiratory sensitizer. Inhalation of vapors may cause irritation and intoxication with headaches, dizziness, and nausea. See Safety Data Sheets for further information. Ingestion may cause irritation. • KEEP OUT OF REACH OF CHILDREN. Avoid contact with skin, eyes and clothing. Wash thoroughly after handling. Avoid breathing vapors. Use only with adequate ventilation. Use impervious gloves, eye protection and if TLV is exceeded or if used in a poorly ventilated area, use NIOSH/MSMA approved respiratory protection in accordance with applicable federal, state and local regulations. DO NOT take internally. Empty container may contain hazardous residues. FIRST AID In case of eye contact, flush thoroughly with water for at least 15 minutes. SEEK  IMMEDIATE MEDICAL  ATTENTION. In case of skin contact, wash affected areas with soap and water. If irritation persists, SEEK MEDICAL ATTENTION. Remove and wash all contaminated clothing. If inhalation causes physical discomfort, remove to fresh air. If discomfort persists, SEEK MEDICAL ATTENTION. INSTALLER RESPONSIBILITY These directions are general guidelines for flooring installations. It is the responsibility of the installer to determine proper drying time of the adhesive, trowel size to be used and acceptability of subfloor conditions. Installations must also be in accordance with flooring manufacturers recommendations. Only flooring that is approved for glue down installations by the flooring manufacturer can be used with DriTac 7300. Floors installed with DriTac 7300 are not warranted against damage caused by wet mopping, flooding, plumbing leaks or other extraordinary circumstances. For any installation not herein recommended, contact DriTac Flooring Products before proceeding. WARRANTY This product is warranted to be free of manufacturing defects. If a manufacturing defect is found within one year from the date of purchase, such defective product shall be replaced. No warranty either expressed or implied is made regarding the performance of this product since conditions under which these goods are transported, stored, used or applied are beyond our control. This warranty is made in lieu of all other warranties either expressed or implied and the seller shall not be responsible for consequential, incidental, special or other damages no matter what the cause. GHS label elements: Hazard pictograms: Signal word: Warning. Hazard statements: Causes skin irritation. Causes serious eye irritation. May cause an allergic skin reaction. May cause respiratory irritation. Precautionary statements: Wear protective gloves: butyl rubber, Ethyl vinyl alcohol laminate (EVAL), nitrile rubber, neoprene rubber. Wear eye and face protection. Wear protective clothing. Avoid breathing vapor. Avoid release to the environment. Wash hands thoroughly after handling. Collect spillage.

EXHIBIT “C” National Wood Flooring Association Installation Guidelines Wood Flooring – Chapter 3: “Solid Parquet Floor”

SECTION II PRODUCT SPECIFIC INFORMATION CHAPTER 3 SOLID PARQUET FLOORING 3/4” & Thinner Unfinished/Factory Finished/Impregnated I. Minimum Acceptable Jobsite Conditions and Checklist See Section I II. Acclimation Guidelines NOTE: Always follow the manufacturers recommendations for acclimation. Upon delivery check wood flooring moisture content (Section V, Appendix AB, AD and AE) to establish a baseline for required acclimation (Section 1, Chapter 1). Acclimation depends on geographic location, interior climate control and time of year. See Definition of Acclimation under Section VI. Refer to Section V, Appendix AD and AE. III. Flooring Grade Levels (Section V Appendix AF) Above Grade: Solid parquet wood floors can be installed successfully above grade level. On Grade: Solid parquet wood floors can be installed successfully on grade level. Below Grade: SOLID WOOD FLOORS ARE NOT RECOMMENDED FOR BELOW GRADE INSTALLATIONS. NOTE: The entire flooring level is considered to be BELOW grade where soil is present along any perimeter wall and is more than 3” above the installed wood flooring level. IV. Subfloor Guidelines – Wood Joist Systems – panel products or solid boards NOTE: Always follow the manufacturers recommendation for proper subfloor. NOTE: Subfloor/Underlayment panels should conform to the USVoluntary Product Standard PS 2-92 or PS 1-95 and/or Canadian performance standard CAN/CSA 0325.0-92 Construction Sheathing. Check underside of boards for codes. 1 Revised June 2002

Chapter 3, Solid Parquet FLoor NOTE: Solid board subflooring should be: 3/4” x 5 1/2”, Group 1 dense softwoods, (SYP, Doug Fir, Larch, etc), No. 2 Common, Kiln dried less than 15% MC. Check subfloor for performance stamp and/or specification agency. Subfloor must be flat,clean,dry, structurally sound,free of squeaks and free of pro- truding fasteners. Test subflooring for moisture according to Moisture Testing Procedures in Section V, Appendix AB. Moisture content should be within 4% of average area environ- mental conditions. Section V, Appendix AD and AE. For installations using mechanical fasteners of 1-1/2” and above, the subfloor sould be flat to within 1/4” in 10’ or 3/16” in 6’. For gluedown installations and installations using mechanical fasteners of less than 1-1/2”, the subfloor should be flat to within 3/16” in 10’ or 1/8” in 6’. For paneled subflooring/underlayment – nailing schedule must be adequate,typ- ical-every 6” along panel ends and every 12” along intermediate supports; all panel edges should exhibit spacing; edge swell should be flattened as necessary. For board subflooring – Boards should be no wider than 6”; installed at 45 degree angle with all board ends full bearing on joists and nailed with 2, 8d nails; 1/4”- 1/2” space should be present between board edges. PREFERRED SUBFLOORING: 3/4” (23/32”, 18.3mm) CDX Plywood subfloor/underlayment (Exposure 1), 4’ X 8’ sheets; OR 3/4” (23/32”, 18.3mm) OSB subfloor/underlayment, with joist spacing 19.2”(475mm) on center or less. MINIMUM: 5/8” (19/32”, 15.1mm) CDX Plywood subfloor/underlayment (Exposure 1) 4’ X 8’sheets, maximum 16” (400mm) on center joist construction Follow panel manufacturer recommendations for spacing and fastening. Typical panel spacing and fastening for joist systems, 1/8”(3.2mm) around perimeter and fastened every 6” (150mm) on bearing edges and every 12” (300 mm) along intermediate supports. For 3/4” (18.3mm) CDX Plywood and 23/32” (18.3mm) OSB, with joist systems spaced over maximum 19.2” (475mm) o/c requires an additional layer of ply- wood. Minimum requirement; 1/2” (15/32”, 11.9mm) CDX plywood subfloor/underlayment,(Exposure 1) 4’X8’sheets. The 1/2”plywood should be off- set by 1/2 panel in each direction to the existing subflooring. The panels may also be laid on a diagonal or perpendicular, with 1/8” spacing between sheets. Nail on a 6” minimum grid pattern-using ring shanked nails. Or brace between joists with 2X6 or wider boards every 24”. Revised June 2002 2

Chapter 3, Solid Parquet FLoor NOTE: Parquet cannot be installed directly to solid board subfloors Board subfloors must have additional underlayment. Preferred requirement; 1/2” (15/32”, 11.9mm) CDX plywood subfloor/underlayment, (Exposure 1) 4’x8’ sheets. Minimum thickness 3/8” underlayment panels. Panels nailed on 6” minimum grid pattern using ring-shanked nails or staples. NOTE: With minimum specified materials , at maximum span and spacing (i.e. greater than 19.2”) flooring will exhibit minimum performance. Minimum per- formance may result in the following conditions: movement, gaps, noises , and with site finished flooring finish delamination. V. Subfloor Guidelines – Concrete Slab NOTE: Always follow the manufacturers recommendation for proper subfloor. Concrete must be flat, dry, structurally sound and clean. Test concrete for moisture according to Moisture Testing Procedures in Section V, Appendix AA. Excess moisture should not be present. Tolerance should be flat to within 3/16” in 10’ or 1/8” in 6’. Substrate should be flattened to tolerance Lightweight concrete (less than 3000 psi) where adhesive used has a higher psi rating than concrete, use with a Subfloor-Floated. RULE OF THUMB: Draw a nail across the top and if it leaves an indentation, it is probably lightweight concrete. Before moisture testing begins, the slab must be cured for a MINIMUM of 30 days. Direct Glue Application NOTE: Always follow the manufacturers recommendation for proper application, proper adhesive and correct spread rate. If necessary, add moisture retarder before applying adhesive. (Section V, Appendix AG) Typical – 3/4”thick parquet requires a vapor retarder over the concrete slab,and spread rate for adhesives 30 – 50 sq. ft. per gallon. Typical – 1/2”and thinner parquet does not require a vapor retarder, and spread rate for adhesive is 40 – 60 sq. ft. per gallon. 3 Revised June 2002

Chapter 3, Solid Parquet FLoor Subfloor – Floated NOTE: Always follow the manufacturers recommendation for proper subfloo.r If necessary, add moisture retarder before applying underlayment. (Section V, Appendix AG) PREFERRED: Subfloor system: 2 layers 1/2” (15/32”, 11.9mm) CDX plywood sub- floor/underlayment, (Exposure 1) 4x8 sheets. MINIMUM Subfloor system: 2 layers 3/8” (10mm) CDX Plywood subfloor/underlayment (Exposure 1) 4’ X 8’sheets. Place first plywood layer with edges parallel to wall, without fastening. Plywood should be placed with 1/8” gaps between sheets Lay second layer perpendicular or at 45 degree angle to first Plywood should be placed with 1/8” gaps between sheets 3/4” minimum expansion space at all vertical obstructions and wall lines Staple, screw, or nail second layer to first layer on 12” grid pattern. Glue Down Subfloor NOTE: Always follow the manufacturers recommendation for proper subfloor. If necessary, add moisture barrier before applying underlayment. (Section V, Appendix AA) PREFERRED: Subfloor: 3/4” (23/32”, 18.3mm) CDX Plywood subfloor/underlayment (Exposure 1),4’x8’sheets. MINIMUM Subfloor: 5/8”(19/32),15.1mm) CDX Plywood subfloor/underlayment, (Exposure 1), 4’x8’ sheets. For single layer system; Apply adhesive per manufacturers recommenda- tions (typical spread rate – 30-35 sq.ft.per gallon with a 1/4”x 1/4”notched trowel), cut plywood to 2’X8’ or 4’X4’ sections; score on the back 1/2 the thickness on a 12”x12” grid; lay sections in a staggered joint pattern in the adhesive; 1/8”spacing between sheets; 3/4”minimum expansion space at all vertical obstructions. Nail Down Subfloor NOTE: Always follow the manufacturers recommendation for proper subfloo.r If necessary, add moisture barrier before applying underlayment. PREFERRED Subfloor system: 3/4” (23/32”, 18.3mm) CDX Plywood subfloor/under- layment,(Exposure 1), 4’X8’sheets. MINIMUM Subfloor: 5/8” (19/32,15.1mm) CDX Plywood subfloor/underlayment (Exposure 1), 4’x8’ sheets Revised June 2002 4

Chapter 3, Solid Parquet FLoor 1/8” spacing between sheets with staggered joints Fasten every 12” and 6” from edge along the border for a minimum of 32 shots per 4’x8” sheet. For load (shot) information, contact your local supplier Areas with higher humidity may require additional nails (shots). 3/4” minimum expansion space at all vertical obstructions NOTE: Fasteners may be powder driven pins, pneumatic driven nails, hand nails, screws, deformed pins, or other fasteners suitable for concrete application. Check with fastener distributor for specification such as length, drill size, and/or shot load where applicable. VI. INSTALLATION NOTE: The styles and types of block and parquet flooring as well as the recom- mended procedures for application vary somewhat among the different manu- facturers. Detailed installation instructions are usually provided with the flooring or are available from the manufacturer or distributor. Test wood subflooring for moisture according to Moisture Testing Procedures in Section V, Appendix AB. Moisture content should be within 4% of average area environmental conditions. Section V, Appendix AD and AE. Test concrete for moisture according to Moisture Testing Procedures in Section V, Appendix AA. Moisture indicators should be within the adhesive and flooring manufacturers specifications. A minimum expansion space equal to the thickness of the installed product must be left around the perimeter and all vertical obstructions. Some 3/4” slat parquet can be nailed down, as long as the pattern continues to have an exposed side tongue in which to nail Lay both blocks and the individual pieces of parquet in adhesive. Use the wood manufacturer’s approved adhesive. Follow the spread rate,trowel size and installation procedure as recommended by the adhesive manufacturer. If recommended by manufacturer, roll floor with proper roller. The most common layout of parquet is with edges of parquet units and the lines they form square with the walls of the room. (see figure 1-1) 5 Revised June 2002

Chapter 3, Solid Parquet FLoor Start by snapping a chalk line through the center of the room (line Y (see figure 1-1). The next line (X)must be exactly 90 degrees to line Y to form a perfect square corner. To ensure this angle, do the following: 1. From the center point (A) of line Y, measure figure 1-1 4 feet along line Y and mark that point (B). 2. From the same center point, measure 3 feet in the general direction of where line X will be and scribe an arc. 3. Return to the original 4-foot mark on line Y and measure 5 feet, scribing an arc that crosses (point C) the 3-foot arc you made in the previous step. 4. Verify all measurements before proceed - ing. 5. If correct, snap a chalk line through the conjunction of the two arcs and the center point of line Y. This will be line X, at an exact 90-degree angle to line Y. An alternate layout is a diagonal pattern,with lines at a 45-degree angle to the walls. For diagonal layout you will start with a diagonal working line in the center of the room.(see fig - ure 1-2) To establish a 45-degree working line: 1. From the center point, measure 4 feet down in each direction on lines X and Y. figure 1-2 2. From each of these points, measure 4 feet and scribe an arc. The conjunction of these arcs creates points D and E. 3. Snap a chalk line between points D and E, and the center point. This line represents a 45-degree angle. Most special patterns can be laid out with the above two working lines. Herringbone will require two lines, one at 90 degrees and the other at a 45-degree angle. These lines must be adjusted to properly center the points of the pattern. Herringbone direction should be installed in accordance with consumer preference. If the pattern is to be installed in the direction of the length of the room, the herringbone working line should be laid out parallel to line Y. (see figure 1-3 and figure 1-4). Line B in this instance must run parallel to line Y and represent the center of he herringbone material. To determine the center of the herringbone material and establish line B: Revised June 2002 6

Chapter 3, Solid Parquet FLoor X axis LINE A Y axis LINE C LINE C LINE B figure 1-3 figure 1-4 1. Begin by laying out a few alternating slats. (see figure 1-4) 2. Snap line A and line B through the corners of the alternating slats. 3. Measure the distance from line A to line B. LINE B The working line should be one-half that dis - tance and run parallel to line Y. Herringbone installation: To begin installation on line B (see figure 1-5),cut a square piece of plywood the size of the herringbone pattern figure 1-5 you are installing. For example, if the herring - bone is 3 inches by 12 inches, cut a 12-by-12 inch piece of plywood. Nail this piece of plywood at your starting point on line B, with one corner of the square pointing in the direction of your layout. VI. EXISTING FLOORING GUIDELINES NOTE: Always follow the manufacturers recommendations for installation over existing flooring. Glue down parquet applications that require the use of PVA adhesives is not rec- ommend over existing sheet vinyl or vinyl and cork tile flooring unless an under- layment is put down first. Underlayment should be in accordance with preced- ing NWFA guidelines. Other types of adhesives may require the use of a primer or vinyl blocker when installing over sheet vinyl or vinyl and cork tile flooring. 7 Revised June 2002

Chapter 3, Solid Parquet FLoor Nail down applications may be successful over existing sheet vinyl or vinyl tile if fastener penetration is not significantly diminished and the subfloor meets mini- mum requirements. NOTE: Particleboard is not generally an acceptable underlayment. Some man- ufacturers approve particleboard as an acceptable underlayment. In such cases follow manufacturers recommendation. Sand off old finish and high spots on existing wood floor and prep to clean, dry, sound, flat subfloor. Repair, re-nail or replace loose flooring products. Wood Flooring can be installed over existing ceramic tile, terrazzo, or marble with prop- er underlayment or adhesives only on manufacturers recommendation. Revised June 2002 8