Set Delayed Mortar Installation/Application
Mortar type should correlate with the particular masonry unit to be used. The specifier should evaluate the interaction of the mortar type and masonry unit specified. That is, masonry units having a high initial rate of absorption will have greater compatibility with mortar that has a high-water retentivity. The material properties of mortar that influence the structural performance of masonry are compressive strength, bond strength and elasticity. Because the compressive strength of masonry mortar is generally less important than bond strength, workability and water retentivity, the latter properties should be given principal consideration in mortar selection. Select mortar based on the design requirements and with consideration of code and specification provisions affected by the mortar.
A sample of the proposed product will be provided by the manufacturer for architectural approval and testing, if required. Preparation of a panel with all materials and systems employed in the final project is imperative. Retain the mock-up or field sample through the completion of the project.
Allow mortar to cure a minimum of 7 days but no more than 28 days before cleaning. Consult manufacturer of the masonry units and cleaning chemicals for further instructions to ensure proper washing procedures.
Clean masonry only with a national proprietary cleaning agent (following the manufacturer’s instructions) or potable water. SPEC MIX products must be kept dry, covered and protected from weather and other damage
Sizes and Equipment
SPEC MIX Set Delayed Mortar is available in 80 lb (36.2 kg) packages for easy hand loading or in 3,000 lb (1,360.7 kg) reusable bulk bags to be used with the various SPEC MIX silo systems. When using the silo system, once the bulk bags of mortar are delivered to the project site, the portable silo is loaded with a jobsite forklift and the product is dispensed into a mechanical batch mixer.
Set Delayed Mortar Mixing Instructions
WEAR IMPERVIOUS GLOVES, such as nitrile.
1. Mixing is best accomplished by using a mechanical mixer to ensure optimal workability and performance.
2. Use clean, potable water; add the amount of water consistent with optimum workability which provides adequate water to satisfy the initial rate of absorption of the masonry units.
3. Mixing times are four to five minutes when using a mechanical batch mixer and should be held consistent from batch to batch.
4. Maintain the same mixing procedures to maintain consistency throughout the project.
5. Tool mortar joints when the surface is thumbprint hard. Keep tooling times consistent.
6. Hand mix mortar only with written approval by the specifier who should outline procedures.
7. Use mortar within 2.5 hours after initial mixing.
8. Retemper mortar only when mixing water is lost due to evaporation.
9. Whenever possible, do not retemper colored SPEC MIX masonry mortars by adding additional water; retempering may affect color consistency.