- Are rebar and wire required to achieve structural loads?
We have constructed single-story structures without rebar and wire. However, such determinations should be made by an engineer or architect based on desired results.
- Are there any certifications for Grancrete™ from any testing laboratories?
Yes. We have third party ASTM data, as well as certification originally completed by Argonne Labs.
- Are there any release agents that work with Grancrete™?
Yes, WD40 or any light oils work well
- Are there temperature limitations that affect the application of Grancrete™?
The temperature range for use is approximately 8° - 110°F. To use Grancrete™ in extremely hot areas, we advise construction of the buildings with the foam panels during the day and spraying the Grancrete™ in the early morning, late in the evening, or at night under lights.
- Can accelerants and retardants be used to control workability time?
Accelerants can be added, but we have not found any retardants that are truly effective, but we are still trying to find a retardant.
- Can Grancrete be applied to construct vertical walls?
- Can Grancrete be used on an ICF exterior wall below grade, such as a basement exterior wall?
Grancrete is currently being used as a below grade exterior wall coating to offer water protection and durability.
- Can Grancrete be used on flat roofs?
Grancrete is in the process of working roof types of applications and will post the results from this process in the future here on Grancrete.net
- Can Grancrete be used on thin-shelled buildings such as ED Domes, or Monolithic Domes?
Grancrete (plus aggregates) have been shown to be an effective coating on a monolithic dome.
- Can Grancrete™ be colored?
Yes, utilizing certain dyes and colored mineral products
- Can Grancrete™ be used as a fireproofing application?
Yes. It is fire-resistant and will maintain its structural integrity up to 2,700°F for 4 hours. It has withstood 2,100°F for 3 continuous days in formal testing.
- Can Grancrete™ be used to waterproof walls?
Yes. We would recommend a minimum thickness of 3/8 inch for this application.
- Can the Grancrete set time be delayed or accelerated, if so, how long?
The normal set time of Grancrete is 15 minutes, both ambient air temperature and water temperature have an effect on the set time. Under hotter conditions, the reaction time can be as short as 5 minutes and under cold conditions the set time can be as great as 45 minutes. Grancrete is in the process of developing approaches to measuring this more precisely.
- Do ultraviolet rays affect Grancrete™?
Grancrete has discovered it blocks a number of types of radiation because it was developed to encounter nuclear waste but the testing for UV impact is still ongoing and results will be available here in the future
- Does Grancrete leach out?
The data from Argonne Labs reflects that the material does not leach. Grancrete is currently seeking a independent, third party to certify this information.
- Has Grancrete undergone structural testing?
The structural test that has been completed is reflected in the attached data link grancrete.net/products/index.cfm We are actively testing specific structural applications and combinations with other materials.
- How can you install the electrical & sanitation elements in the appropriate areas after Grancrete has been applied?
Typically these installations are roughed in prior to the Grancrete application, if installed after Grancrete, these conduits can be installed by using a diamond-cut saw or diamond-tip drill.
- How does Grancrete adhere(stick) to metals & plastics, not just EPS?
Grancrete creates a "covalent bond" to any porous material,including concrete,stone,brick,wood and Grancrete itself.
- How does Grancrete™ adhere to rebar?
Grancrete actually bonds to the steel, not just encapsulating it as portland cement does
- How durable is Grancrete™ against traffic and constant vehicle movement?
Grancrete™ is very durable because of its high tolerances to heat, different pH levels, and the effects of the elements. In addition, once Grancrete™ cures, it will not expand or contract in response to temperature changes.
- How is Grancrete™ applied and how labor-intensive is it?
Grancrete can be sprayed, troweled, or poured onto any porous surface. It takes a crew of 2 to operate the mixing and spraying process for large jobs.
- How is the Grancrete™ shipped?
Grancrete™ is shipped on pallets, with 40 50-pound bags per pallet, or in plastic pails of 50 pounds each.
- How much training time is required before one can use Grancrete™?
Attending a 2-day course is strongly recommended but not required.
- How much weight can Grancrete support?
It depends on use and application.
- If Grancrete™ is used over existing conditions, what is the prep work needed before application?
The only prep work would be providing a clean surface upon which to apply Grancrete™. This may require equipment for power-washing of old surfaces, to remove grease and oil.
- If used on flat slabs, are control joints required?
No, control joints are not required because Grancrete™ does not expand or contract.
- Is Grancrete™ a concrete replacement or just a topping product?
Grancrete is a topping coat, a protective coating, and depending on the application it can be used as a replacement for concrete (high early strength)
- Is Grancrete™ a liquid, gel, or loose grout?
Grancrete™ is a fine powder material with fibers in the mix. All that is required to use it is water . Aggreates may be added
- Is Grancrete™ a self-leveling product?
Yes, Grancrete™ is self-leveling with the addition of fine sand
- What are the physical properties of Grancrete™?
Grancrete™ is a blend of in-organic compounds that are non-toxic, non-hazardous, and environmentally friendly.
- What are the types of equipment used to mix & apply Grancrete?
Grancrete has experience with four (4) different pieces of equiptment: 1)Plastic drum sprayer, 2)Hopper based sprayer(small), 3)Gunite machine and 4)Continuous mixer/sprayer combination.
- What is the length of workability before Grancrete™ is cured?
Approximately 15-40 minutes after water has been added, depending on the ambient temperature.
- What is the minimum depth for compressive strength?
We recommend that an architect or construction engineer make this determination, depending on the job being done and the desired weight load expected.
- What is the proper method of disposal for Grancrete™, if the need should arise in the future?
We are in the process of getting a green label for Grancrete™. Once that is obtained, the material could be pulverized by crushing equipment and mixed with soil.
- What is the R factor?
Grancrete does not provide high numbers in respect to being an insulator. Grancrete serves as a sealant to keep water and humidity out all while protecting the underlying insulation from physical damage.
- What is used to cleanup and remove any overspray or extra material?
If the Grancrete™ has hardened, a chisel can be used. If it is still wet, a rag can be used to remove excess material.
- What is weight of Grancrete; relative to concrete?
Grancrete is about 20% lighter than standard concrete. The weight and density of Grancrete is 2.1gm/cm
- What substances can alter or affect Grancrete™?
Products that have a pH of 2 or lower or a pH of 12 or higher can affect the product.
- What testing has Grancrete undergone,completed or in the process of completing?
Please see this link for the testing already completed (if link doesn't work on your computer,copy&paste into your browser bar) grancrete.net/products/index.cfm.
Grancrete is engaged in research,development & testing with numerious private labs and we are pleased to be partnered with North Carolina State University's Constructed Facilities Laboratory, a public US university and worldwide leader in this industry for testing and research.
- What type of equipment is required to use Grancrete™?
No special equipment is required if Grancrete™ is poured or troweled.
- What, if any, are the health hazards associated with Grancrete™?
There are none known. This is a "green" product and is nontoxic to humans and the environment. However, we do recommend that a dust mask be worn during the opening of bags and mixing of Grancrete™.
- When applying Grancrete, how do you cover openings, like windows & doors?
Use plastic taped to the surfaces.
- Where can the equiptment to mix & apply Grancrete be found?
1)plastic mixers-available through-out, they are small & mobile, 2)Hopper-based sprayer-requires a mixer & is suitable for smaller jobs, 3)Gunite machine-large applications like shockcrete, 4)Various models of mixers/sprayers- we recommend using Machine Technologies
- Where is Grancrete produced?
Grancrete is being produced at a plant in the Southeastern part of the US
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