SPECIFICATIONS – Printable : PDF
Version – Word
Submit color samples for selection from manufacturer’s group A, B, C, D or E. Submit product literature, certifications, test reports and full size sample(s) of each color specified.
Concrete blocks for grinding shall conform to ASTM C90. After the initial grinding process to expose the variegated colors of the natural aggregates, the pores and interstices of Verastone Plus filled and polished units are filled with a cementitious grout and polished smooth in a multi-stage polishing process. Both the ground face and filled and polished surfaces shall have a factory-applied heat-treated acrylic or water-based sealer finish.
All units contain a manufacturer-approved integral water-repellent CMU admixture at the time of manufacture.
Units shall conform to ASTM C1262 with respect to freezing and thawing. Verastone Plus filled and polished units shall conform to the requirements of ASTM C744 with respect to Adhesion, Abrasion, Color Change and Resistance to Crazing. Unlike polished block, filled and polished units offer graffiti and stain resistance.
All Trenwyth products conform to ASTM E2432-05 as it pertains to the environmental, economic and social sustainability relative to buildings. Both Verastone and Verastone Plus contain pre-consumer recycled content. Contact your Trenwyth representative for details.
Trenwyth products offer high thermal mass properties, regional materials and low life-cycle costs. Units shall have a tighter, smoother face. Mold and moisture resistant, units are easy to clean (never paint or refinish). Factory-applied water-based sealer emits low VOCís. Available in a wide color selection, custom colors and unique shapes and sizes, these units are ideal for interior and exterior applications. The structural integrity of the unit results in a one-step, single trade installation process. Verastone Plus units are graffiti resistant. Units are distributed nationally.
Fire Resistance: Fire rated for up to 4 hours. Define hourly ratings required by NCMA TEK Notes, available at www.trenwyth.com.
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.
A full size unit is required to illustrate color and texture for approval. Manufacturer requires a sample panel be installed at the jobsite prior to installation of any Trenwyth product. This panel will represent both the quality of the product and the workmanship to be expected for the project. The panel must be approved by either the owner or architect for the project. Manufacturer will provide 4" units for a 4' by 4' sample panel at no cost for the material (excluding freight to site).
Delivery, Storage and Handling
Units shall be delivered to the jobsite on covered banded pallets with cardboard between layers. 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 surfaces.
Protection of Work: Cover walls 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.
Part 2 – Products
Verastone® recycled ground face masonry units
Verastone® Plus recycled filled and polished masonry units
Anchor Concrete Products (800) 233-1924
One Connelly Road • Emigsville, PA 17318
Northfield Block Company (800) 358-3003
3400 E. Bungalow Road, Morris, IL 60450
Colored matching or contrasting mortar is available from manufacturer. Consult NCMA TEK Notes, available at www.trenwyth.com, for mortar type and specifications. For all exterior mortar, use matching manufacturer-approved water repellent mortar admixture following manufacturer's instructions. Consult manufacturer for recommendations.
Sizes and Shapes
Surfaces are manufactured to provide finished dimensions of 7-5/8" x 15-5/8" ± 1/8". Bed depth dimensions for single face units are 3-9/16", 5-9/16", 7-9/16", 11-9/16" ± 1/8". Two face units are 3-1/2", 5-1/2", 7-1/2", 11-1/2", ± 1/8". Nominal 2", 4", 6", 8", 10" and 12" standard block thickness are available as well as all standard block shapes. High-strength units for special structural requirements, over-sized units, and metric shapes and sizes are also available.
Carefully following manufacturer’s instructions, use Burnished Custom Masonry Cleaner by PROSOCO (dilute 1 part to 3 parts clean water). Available from manufacturer. Do not powerwash.
CAUTION! Never use Muriatic Acid solution or any cleaner with an acid base on units.
Part 3 – Execution
Laying Masonry Walls
Draw blocks from more than one pallet at a time during installation. All exterior mortar shall include manufacturer-approved 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, available at www.trenwyth.com, 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 or filled and polished 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
- 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.
- Tool all mortar joints when thumbprint hard into a concave configuration.
- Care should be taken to remove mortar from the face of masonry units before it sets.
- Tuckpoint the joints of scored units for proper appearance. All exterior scored units must be tuckpointed to prevent water penetration. NO
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, available at www.trenwyth.com, for proper flashing and drawings.
The 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.
Keep walls clean daily during installation using brushes, rags and the burlap squares supplied on the pallets. Do not allow excess mortar lumps or smears to harden on
the finished surfaces. Harsh cleaning methods after walls have been erected will mar the surface of the blocks.
Clean the completed walls with PROSOCO Burnished Custom Masonry Cleaner (dilute 1 part to 3 parts clean water), strictly following the manufacturer's instructions – including thorough rinsing. Do not use acid or abrasives
on the finished surfaces. Failure to strictly follow manufacturer’s instructions can result in permanent damage to the finished faces. Do not apply Burnished Custom Masonry Cleaner with pressure spray above
50 psi. Do not powerwash.
Field Coat Application
For completely finished walls, a finish coat of TRENDCOAT® Acrylic (minimum 20% solids content) or TRENDCOAT® WB (water-base) is recommended. Apply
to walls after cleandown and when the walls are dry. Apply the acrylic evenly to cover the entire surface without forming drips or runs. For maximum coverage and best appearance, apply TRENDCOAT Acrylic or TRENDCOAT WB with airless spray equipment. Consult manufacturer for further information. This clear, high-solids acrylic, provides moisture resistance and helps to cover any
scuffs or scratches that may occur during handling and/or installation. TRENDCOAT also offers excellent graffiti resistance for Verastone Plus filled and polished units.
Properly installed and cleaned, units need virtually no maintenance other than routine cleaning (i.e. Pinesol or Fantastik). Graffiti, paint or dye stains may need special cleaning methods and products such as Trenwyth
Graffiti Wizard® environmentally friendly cleaner. Contact manufacturer for specific cleaning recommendations.
Consult NCMA TEK Notes, available at www.trenwyth.com, for proper installation of concrete masonry units.