Mortar Mix

When you need a mortar with rapid strength gain, high durability and low shrinkage, use Rapid Set® Mortar Mix. Use for vertical and overhead applications. A high-performance blend of Rapid Set® hydraulic cement and quality sand, Mortar Mix is non-metallic and no chlorides are added. Mortar Mix is durable in wet environments, sets in 15 minutes and ready for traffic in 1 hour.

Mortar Mix is similar in appearance to portland cement-based mortars and may be applied using similar methods. Mix Mortar Mix with water to produce a workable, high-quality mortar that can be used for general concrete repair, stucco and plaster repair, one-coat exterior plaster, mortar beds, underlayments and formed work. Apply Mortar Mix from ½ inch to 6 inches thick. One 55-pound bag yields approximately 0.5 cubic feet.



The Datasheet explains the performance and technical characteristics of Rapid Set® Mortar Mix.  It also shows how to use Mortar Mix (i.e. surface preparation, mixing, placement and curing).

The Spanish Datasheet is also available here.


The Safety Data Sheet (SDS) outlines information and procedures for handling and working with Rapid Set® Mortar Mix.  It includes physical and chemical property information, potential hazards, emergency procedures and CTS’s contact information.


The Specification gives a detailed statement explaining the type of jobs to specify Rapid Set® Mortar Mix for, the scope of work, thicknesses, performance requirements and usage.

Click here for word document

Standard Practices

Q: What is Rapid Set® Mortar Mix?
Rapid Set® Mortar Mix is a blend of high-performance Rapid Set® Cement with washed plaster sand. It provides rapid strength gain, high durability and low shrinkage. Use for horizontal, vertical, and overhead plaster and concrete projects. Simply mix with water and it will reach structural strength in one hour.

Q: Is this a modified portland cement product?
No. The high-performance properties come from the Rapid Set Cement in the mix.

Q: How soon can I color coat?
Apply color after the product is hardened and dry which usually takes 1 to 4 hours.

Q: How soon can Rapid Set be painted/coated/sealed?
Rapid Set reduces the waiting time prior to coating. Under dry conditions, water based coatings such as latex paint can be applied after the products is hardened and dry which usually takes 1 to 4 hours. Solvent based and Impermeable coatings such as oil based paint and epoxy can be applied in 16 hours.  Experience has shown that some coatings can be applied in much less time. Follow the coating manufacturer’s recommendations for surface condition.

Q: Is a bonding agent necessary?
Bonding agents are not required. Proper surface preparation is the main component in achieving a good bond. If bonding agents are desired, they should be used as a supplement to good surface preparation, not as a substitute.

Q: Can I blend other products with Rapid Set Mortar Mix?
Blending with other products may give unpredictable results and is not recommended. The use of Rapid Set approved additives and various colors are acceptable.

Q: How thick can I apply this product?
From ½ inch to 6 inches.

Q: Is Rapid Set Mortar Mix air entrained?
Rapid Set Mortar Mix is air entrained except for the product made in California.

Q: How do I mix it?
Just add water. The use of a mechanical mixer such as a mortar mixer or drill mounted mixer is recommended. To maximize working time, organize work so that all people and equipment are in place before mixing.

Q: How do I place and finish it?
Using traditional methods, place and strike-off to desired level. Rapid Set is fast and does not bleed water so apply your final finish immediately after placing. Organize your tools and people so you can work quickly.  On flat work, fill to full depth and proceed horizontally. Do NOT place in layers.

Q: How do I cure Rapid Set Mortar Mix?
A: Water cure all Rapid Set Mortar Mix installations. The objective of water curing is to maintain a wet surface until the product has achieved sufficient strength. Begin curing as soon as the surface has lost its moist sheen and continue for a minimum of 1 hour.

Q: What are common applications for Rapid Set Mortar Mix?
Rapid Set Mortar Mix is an all-purpose repair product. The most common applications are vertical and overhead applications, and general concrete repair.

Q: How do I increase the working time?
You can increase the working time by lowering the mix temperature or using set retarding additives. Lower the mix temperature by keeping product cool and using chilled mix water. Rapid Set® SET Control® additive will increase working time and is available through our Concrete Pharmacy®.

Q: Can I use color?
Yes. The color of Rapid Set Mortar Mix can be modified by using dry powder pigments designed for use in cement mixes.

Q: How do I prepare the surface?
Roughen the surface and remove all damaged or contaminated concrete. Make sure the repair surface is not contaminated by oil, paint, acids, dirt or other materials that will prevent a good bond. Immediately prior to placement, saturate the repair surface with water then remove any standing water.

Q: How much do I need?
One bag of Rapid Set Mortar Mix yields approximately 0.5 cubic feet. That is one square foot, six inches deep. For plastering, it will cover 8 square feet at ¾-inch thick. If you need an answer more specific to your application, use our Concrete Calculator.

Q: Can I use it in wet applications?
Yes. Rapid Set Mortar Mix is made with Rapid Set® Cement, which is a hydraulic cement. A hydraulic cement hardens under water.

Q: What is the shelf life?
When stored in a dry location, in an undamaged package Rapid Set Mortar Mix has a shelf life of 12 months.

Q: Does temperature affect Rapid Set Mortar Mix?
Cold temperatures will slow the setting time of Rapid Set Mortar Mix and warm temperatures will speed it up. Greater changes in temperature will have a more pronounced affect.

Jobs & Applications

  • Hyatt Andaz Maui Luxury Resort in Wailea, HI, Swinerton Incorporated (leveling of units, vertical restoration, balcony spall repairs, grouting, skim coating of walls)
  • Longhorn Village Retirement Community in Austin, TX, Manhattan Construction & Fees Associates (wall repairs)
  • Interstate 70 Bridge Repair in Denver, CO, American Civil Constructors (structural repairs of bridge’s substructure)
  • BuzzOatsBuilding in Phoenix, AZ (structural repairs of wall)
  • Forever 21 Headquarters in Montebello, CA, RestoCrete (pre-leveled floor)
  • SkechersDistributionCenter in Rancho Belago, CA, Inland Concrete Constructors (general patching to patching of the pick-up points on the panels and weld plates)
  • Qualcomm Stadium in San Diego, CA, Nielsen Dillingham (repairs: slabs, spalls, overlays and precast patchwork)
  • The Pentagon in Washington, DC, Concrete Protection & Restoration, Inc. (exterior wall repair and interior structural repair)
  • Fry’s Foods in Apache Junction, AZ, Questmark (filled in core holes on floor)
  • Bone Fish Grill Restaurants in the U.S., Creative Concrete Surfaces (underlayment)
  • Caltech’s South House Complex in Pasadena, CA, DF Perez (grout in brick through the walkways and entryways and blowouts on the walls)
  • Vigo Food Manufacturing Facility in Tampa, FL (floor rehab overlay 1 inch to 4 inch pour)

Leed Product Evaluation

TechnicalSupportWhether you’re working on a time-sensitive project and need answers, or evaluating and choosing the right cement products, or looking to achieve specific results, we are here to help. Get answers to your questions from our technical support team. Find and download useful information from our website. Ask us to help get your construction team up to speed by requesting a jobsite demonstration or educational seminars.

ConcreteCalculatorLearn how Rapid Set’s strength, speed and sustainability help you get better results and finish your jobs sooner. These Charts will show you how.

ProductEvaluationLEED product evaluations summarize a product’s ability to contribute to a variety of LEED credits. These credits include Solar Reflectivity (SS7), Regional Materials (MR4), Recycled Content (MR5), VOC Content (EQ4) and Innovation in Design (ID1).

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