Part 1- General

SUBMITTAL
Submit color sample(s) of each color specified from manufacturer's series. Submit product literature, certification, test reports, full size sample(s) of each color specified or selected.

QUALITY ASSURANCE
All high density prefinished concrete masonry units shall be PRAIRIE stone masonry units manufactured by Northfield Block Company. All units shall conform to ASTM C90-96 and shall have either a ROCK FACE or GROUND FACE finish as shown on the drawings.
Field Constructed Mock-ups: Construct a sample panel, no less than 4' x 4', of units of each color and size to be used in the project. The cleaning agent and method should also be determined at the time sample panel is constructed.

DELIVERY, STORAGE, AND HANDLING
PRAIRIE stone units shall be delivered to the jobsite on banded wood pallets. Each exposed face shall be protected by a plastic protective layer. Each edge of a cube shall be protected by a premolded edge protector. Each cube shall be covered with a clear plastic wrap. Pallets shall be stored in single-stacks on level ground and covered with a waterproof covering (e.g., tarpaulins) to protect the units from inclement weather. Units must be handled carefully to avoid breakage and damage to the finished surfaces.

PROJECT/SITE CONDITIONS AND HANDLING
Cover walls each day after installation to keep open walls protected and dry.

Part 2- Products

PRODUCT NAME
PRAIRIE stone Masonry Units.

MANUFACTURER
Northfield Block Company
One Hunt Court
Mundelein, Illinois, 60060
847-816-9000
847-816-9072 (FAX)
www.northfieldblock.com

Part 3- Execution

LAYING MASONRY WALLS
Lay units using the best concrete masonry practices. Install only quality units; reject all defective units. Align units level, plumb, and true with uniform, carefully-tooled 3/8" wide joints on the finished side of the wall. Draw blocks from two or more pallets at a time during installation. Use a water repellent mortar additive, following the manufacturer's instructions, for all exterior walls

INSTALLATION
Lighting: Provide adequate lighting for masonry work by placing all lighting a reasonable distance from the wall for even illumination. Do not use trough lighting.
Cutting: Make all unit cuts, including those for bonding, holes, boxes, etc., with motor-driven masonry saws, using either an abrasive or diamond blade. Cut neatly for best appearance.

INSPECTION
The facing shall be free from chips, cracks, crazes or any other imperfection that would detract from the overall appearance of the finished wall when viewed from a distance of five (5) feet at right angles to the wall with normal lighting.

FLASHING OF MASONRY WORK
Install flashing at locations shown in the plans and in strict accordance with the details and the best masonry flashing practices.

WEEP HOLES AND VENTS
Install weep holes and vents at proper intervals (32" O.C. and 2" long, above bed joints, typical) at courses above grade, above flashing, and at any water stops over windows, doors, and beams.

CLEANING
Keep walls clean daily during installation using brushes, rags, and burlap squares. Do not allow excess mortar lumps or smears to harden on the finished surfaces. Remove green mortar with burlap or a dry cloth. Harsh cleaning methods after walls have been erected may mar the surface of the units.

FINAL CLEANDOWN
No ACID or ACID base solutions shall be used in the cleaning of PRAIRIE stone units. A detergent masonry cleaner shall be used following the manufacturer's instructions and the surface shall be thoroughly rinsed with clean water.

MAINTENANCE
PRAIRIE stone units, properly installed and cleaned, need virtually no maintenance other than routine cleaning with standard commercial grade cleaning agents. Graffiti, paint or dye stains may need special cleaning methods and products. Contact manufacturer for specific cleaning recommendations.

INTEGRAL WATER-REPELLENT ADMIXTURE
Description: An integral liquid polymeric admixture mixed with concrete during production of all PRAIRIE stone units which becomes an integral part of the cement matrix being locked into the concrete masonry unit to provide resistance to water penetration to achieve a Class E Rating as stated in E514-74. For a complete water repellent wall it is recommended that this admixture is added to the mortar. Product: DRY-BLOCK block Admixture by W.R. GRACE & CO. - CONN.

INSTALLATION RECOMMENDATIONS
. Cavity wall construction is recommended for exterior walls, with proper flashing, venting, and weep holes.
. A complimentary or matching mortar color is recommended when using PRAIRIE stone units.
. Continuous horizontal joint reinforcement is recommended in the exterior wythe every 16" or every course with 12" and 16" high units.
. Control joints are recommended approximately every twenty (20) feet. Application of Dow Corning sealant #695 is recommended at vertical joints.

LIMITATIONS
. The facing is not intended for use as an impervious surface.
. Acid solutions should not be used as a cleaning agent or in direct contact with the facing.
. The facing should not be continuously exposed to temperatures above 250 F.