GUIDE SPECIFICATION
Division 7
THERMAL AND MOISTURE PROTECTION
Section 07240
PRESWITT N.C. (Noncombustible) EXTERIOR INSULATION
AND FINISH SYSTEM (Mineral Wool)
 
PART 1. GENERAL
1.1 DESCRIPTION

.1 Work included: The work described in this section includes the supply and installation of the Exterior Insulation and Finish System, as indicated on the drawings and as specified. .

2 Related Work Under Other Sections: STEEL STUDS AND FURRING: Section EXTERIOR GYPSUM SHEATHING BOARD: Section SEALANTS: Section (See Note 3)

1.2 QUALIFICATIONS
.1 The Exterior Insulation and Finish System shall be installed by a Contractor approved and certified by the system manufacturer. Certification must be in force at the time the project is bid and contracted for.
1.3 SUBMITTALS

.1 Submit to the Architect, for approval, duplicate samples of finish coating of color and texture selected by the Architect. Samples shall be made by applicator utilizing tools, materials, and techniques proposed for installation.

.2 Obtain Architect's approval of samples before ordering materials and proceeding with work.

1.4 PRODUCT DELIVERY, STORAGE AND HANDLING

.1 Store packaged materials in original containers with manufacturer's seals and labels intact, with each production lot identified by batch number. All lots with same batch number shall be stored together.

.2 Prevent damage to materials during handling and storage. Keep materials under cover and free from dampness.

.3 Store products in a cool, dry place out of direct sunlight, protected from the elements and from damage.

.4 System materials shall be stored at a temperature of not less than 5°C (40°F).

1.5 JOB CONDITIONS

.1 Ambient temperature must be no less than 5°C (40°F) during installation and until the adhesive and coatings are dry (minimum 24 hours).

.2 Construct proper free standing scaffolds 460 mm (18") from the wall surface to allow continuous uninterrupted application.

1.6 PROTECTION

.1 Protect adjacent areas from damage resulting from the installation of the system. All finish work shall be protected at the end of the day or completion of a section.

.2 Sections of the work must be protected from adverse weather conditions during the application and until the coatings are dry.

PART 2. PRODUCTS
2.1 MATERIALS

.1 Exterior Insulation and Finish System: The system shall be as manufactured and supplied by Preswitt Manufacturing Ltd., and comprised of insulation board, adhesive compound, reinforced basecoat and acrylic finish.

.2 Insulation Boards: Shall be Preswitt Mineral Wool Board with a nominal density of 8 lbs/cu.ft. Thickness shall be as indicated on the drawings.

.3 Adhesive Compound: Shall be Preswitt Adhesive Compound.

.4 Reinforcing Fabric: Shall be a balanced, openweave glass fibre fabric, treated for compatibility with the system materials. Fabric shall be supplied by Preswitt Manufacturing Ltd.

.5 Heavy Duty Reinforcing Fabric: Shall be balanced, openweave glass fibre fabric treated for compatibility with the system materials and used in high impact areas only. Fabric shall be supplied by Preswitt Manufacturing Ltd.

.6 Basecoat: Shall be Preswitt N.C. Basecoat in 25 kilo bags.

.7 Portland Cement: Type 10 Normal Portland Cement conforming to CSA A5-1977 or Type 1,1-11, or 11 meeting ASTM C150.

.8 Mechanical fasteners if required, shall be as recommended be Preswitt Manufacturing Ltd.

.9 Primer: Shall be Preswitt Acrylic Superbond reduced 50/50 with water before application.

2.2 MIXING AND PREPARATION

.1 Adhesive Compound: Drill-mix with Portland Cement in a ratio of 1:1 by weight.

.2 Basecoat: Add 6 Litres of water by weight to each 25 kilo bag of N.C. Basecoat and mix to a trowelable consistency.

PART 3. EXECUTION
3.1 INSPECTION

.1 Before commencing ensure that environmental and site conditions are suitable for the installation of the system.

.2 All areas, to receive the system shall be sound, flat, even and free from irregularities.

.3 The substrate shall be a type approved by Preswitt Manufacturing Ltd.

.4 Where exterior gypsum sheathing is the specified substrate, ensure that it meets the required standard, is clean, dry, properly fastened and shows no sign of deterioration or defects.

.5 Wall surfaces shall be free of ice and frost.

.6 Ensure that all surfaces are free from loose particles, foreign materials, form oil and traces of any other releasing agents. Any discrepancies shall be reported to the Architect or General Contractor, and rectified before the work proceeds. Commencement of work indicates acceptance of conditions.

3.2 INSTALLATION

.1 Using a 3/8" notched trowel apply the Adhesive Compound to the back of the insulation in a horizontal manner.

.2 Press and secure the Insulation Board onto the wall surface. Ensure solid contact. Boards shall be placed from a level baseline with vertical joints staggered and all joints butted tightly. Boards shall be flushed and the insulation wall surface left flat and even. Mechanical fasteners, if required, will be spaced as directed by the engineer.

.3 Evenly apply the specified Basecoat, 2 mm (1/12") thick, to the exposed surface of the insulation board .

.4 Embed the Standard Reinforcing Fabric in the wet Basecoat, lapping the joints a minimum of 60 mm (2.1/2"); trowel smooth leaving no mesh visible. For high impact areas Heavy Duty Reinforcing Fabric shall be embedded in a Basecoat layer in a similar manner; the fabric shall be butt-jointed, with no laps, and allowed to dry for at least 24 hours. This shall be done prior to installing the Standard Fabric reinforced Basecoat. Both reinforced Basecoats are necessary for high impact areas. The surface to receive the finish material shall be flat and even in all directions with no high points especially at mesh laps.

.5 Apply Finish Coating with a steel trowel and obtain texture by use of a plastic trowel. Coverage shall be in accordance with the manufacturer's instructions.

.6 Installation of the Exterior Insulation and Finish System shall be done in strict accordance with the contract documents, and the manufacturer's written instructions. The finished work shall match approved samples, be uniform in colour, texture and be free from defects detrimental to appearance and performance.

SPECIFICATION NOTES

1. This guide specification is basic and must be adapted to suit the requirements of individual projects. Consult the manufacturer for specific recommendations.

2. This guide specification is prepared in accordance with Construction Specifications three part section format and should be included under Division 7 - Thermal and Moisture Protection as Section 07240, in accordance with CSC/CSI Master Format for specifications.

3. Insert list of related work specified in other Divisions, such as steel studs, exterior gypsum sheathing, sealants, flashings, etc. Sealant compounds should be compatible with Preswitt Wall System components. Insert also the appropriate section number.