IMPORTANT! Before You Begin:
Northfield requires that you order a full size unit to illustrate color and texture for approval. Northfield requires a sample panel be installed at the jobsite prior to installation of any Northfield products. This panel will represent the quality, color and texture of the product and the workmanship to be expected for the project. Either the owner or the project architect must approve the panel. Failure to produce a sample panel may result in loss of warranty. Northfield will provide 4″ units for a 4′ x 4′ sample panel at no cost for the material (not including freight to the site).
Delivery, Storage and Handling:
Mesastone masonry units shall be delivered to the jobsite on covered banded pallets with cardboard between the layers. Keep protective block covers on the blocks until installation. Store pallets in single stacks on level ground and cover with waterproof covering (e.g., tarpaulins) to protect the blocks from inclement weather. Handle blocks carefully to avoid breakage and damage to the finished surface.
Project Site Conditions:
Protection of Work: Cover walls, including open tops, each day after installation to keep open walls protected and dry. After units are installed, they should be protected from damage by other trades performing operations that can stain or otherwise damage the finished surfaces by covering walls with plastic. Corners should be protected from damage after installation by covering them with plywood.
Do not, under any circumstance, install a damaged unit that does not conform to the requirements of ASTM C90. If units have been damaged during transit, contact Northfield immediately.
Laying Masonry Walls:
Draw blocks from more than one pallet at a time during installation. All exterior mortar shall include matching water-repellent additive added to each batch in the appropriate dosage rates for mortar type (M, S or N) per manufacturer’s instructions.
Refer to NCMA TEK Notes, for Hot and Cold weather construction practices.
Lay units using the best concrete masonry practices. Install only quality units; reject all defective units as defined by ASTM C90. Lay blocks with the faces level, plumb and true to the line strung horizontally at the ground face. Units shall have uniform, 3/8″-wide joints both horizontally and vertically on the finished side of the wall. Tool joints neatly after they are finger-hard to make them straight and uniform. Size and place cut pieces appropriately to maintain consistency and bond. Complete masonry construction using procedures and workmanship consistent with the best masonry practices.
Lighting: Provide adequate lighting for masonry work by placing all lighting at 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 and locate for best appearance.
Mortar Bedding and Jointing:
1. Lay units with full mortar coverage on head and bed joints taking care not to block cores to be grouted or filled with masonry insulation.
2. Tool all mortar joints when thumbprint hard into a concave configuration.
3. Care should be taken to remove mortar from the face of masonry units before it sets.
4. Tuckpoint the joints of scored units for proper appearance. All exterior scored units must be tuckpointed to prevent water penetration. NO RAKED JOINTS.
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 at courses above grade and at any water stops over windows, doors and beams. Consult NCMA TEK Notes, for additional flashing information.
The textured faces shall conform to the requirements of ASTM C90 when viewed from a distance of twenty (20) feet at right angles to the wall with normal lighting.
Consult NCMA TEK Notes, for proper installation of concrete masonry units.
* The facing is not intended for use as an impervious surface.
* Acid solutions and HCL acid-based cleaners should not be used as a cleaning agent or in direct contact with the facing.
* Mesastone facings should not be continuously exposed to temperatures above 250ºF.