Questions and Answers

1. What kind of concrete grinder do you use? 

For our garage and smaller commercial projects we use a Lavina 21X planetary grinder which incorporates nine diamond embedded tools to provide a level surface with good profiling and material removal. An attached dust collector safely removes most all of the concrete dust for a clean, safe work environment while preparing the concrete surface to accept the resinous coatings.  Smaller grinders can leave noticeable waviness in the concrete surface which can be distracting to the final product. When needed, we have local access to much larger grinders or shot blasters to appropriately prepare the concrete.

2. Do you typically use a wet grinding process?

For our typical residential garage, patio, or interior project, we do NOT use a wet grinding process. Introducing water into the coating process can create long term problems with the coating adhesion. Since concrete is more like a hard sponge than an impervious solid material, any water incorporated into the process can penetrate into the concrete and potentially create osmotic pressure causing future blistering or delamination of the coatings during its service life.

3. Do you typically use an acid etch in conjunction with the grinding process?

Acid etching is NOT a recommended practice. Most all resinous coatings do not benefit from an acid pH situation. In addition, it is impossible to get an “even” etch across the entire surface. If an acid etch is used, the installer needs to thoroughly neutralize with liquid ammonia, or baking soda. Putting more liquid into the concrete is also not good and using sodium bicarbonate does not provide a thorough way to neutralize the acid. In most cases, more acid is left in the concrete than is used/removed, leaving a poor environment for the coating application. For these reasons, we do NOT use an acid etch in our typical process.

4. Will a clear polyurethane or polyurea coating over epoxy help to reduce/eliminate the UV degradation of epoxy?

No, a clear overcoat of polyurethane, polyurea, or polyaspartic will not improve the UV degradation of epoxy. It may slow the process some, but it will not stop the ambering/yellowing of the epoxy. The only way to stop the ambering process of epoxy is to “bury” the epoxy with a pigmented middle/top coat of UV stable polyurethane, polyurea, polyaspartic,  or other decorative material (flakes/quartz). A clear coat of polyurethane, polyurea, or polyaspartic can be added as a final, UV stable clear coat to produce the final shine/gloss/scratch resistance desired by the customer.

 

5.  Do you take credit cards? Or other payment?

Yes, we are set up with SQUARE, so can take most major credit cards. As long as the project is over $1,000 we will waive the additional credit card charges. Otherwise, we will accept cash and check. 

 

6.  Is a polyurea or polyaspartic type assembly that much better than an epoxy assembly?

Polyurea or polyaspartics certainly have some advantages. Cure rates are much faster, they are UV stable, have low to little VOC’s, a very clear finish, are more flexible than epoxy, and bond well to properly prepared concrete. The materials are more expensive and labor to install is typically more expensive due to the faster cure rates – but that typically means a faster return to service. They don’t do quite as well against battery acid, as do epoxy or polyurethane.  Polyaspartics can be applied slightly heavier than a polyurethane, but not as heavy as an epoxy (both polyurthane and polyaspartics can trap CO2 and create bubbles in the finished coating). So as a top coat, they have numerous advantages over epoxy.

As a base or binding coat to concrete, some of the advantages are lost. Yes, if you need a fast turnaround project, they can be beneficial (there are fast cure epoxies which can do the same for less). We must consider some facts about concrete first. Concrete has great compressive strength, but much less tensile strength. In fact, its tensile strength is only about 10% of its compressive strength. This is why concrete cracks! So a 4000 psi concrete would only have about 400 psi of tensile strength! Thus the use of a polyaspartic with very high psi bond strength is lost on the fact that the concrete will fail way before the bond between the concrete and polyaspartic.  Epoxy (quality commercial/industrial) have only slightly lower bond strengths but which still tend to exceed the tensile strengths of concrete (per ASTM D-4541). Also, we must note that the top surface area of a concrete slab is weakest area of the concrete. 

 

7.  Can you provide information on the product manufacturer?

Yes, we can provide all a data sheets for each of the resinous products we will apply to the concrete surfaces. We are committed to using products which are best in class and provide documented technical specifications. We currently use Arizona Polymer Flooring, E2U, and MiraCote products for most of our projects.

 

8.  Do you use low VOC coatings?

Yes, most of our coatings are low VOC products. Depending on the application, we will work to engineer systems which have the best long term service life for their intended usage. Some applications will be better served by solvent based products which may not be classified as low VOC products, but we will always make sure the customer is aware of any high VOC products being used in the assemblies. Weather can also effect the use of certain products.

 

9.  Can you provide a written quote with the details of the installation?

YES! We always provide a written quote which will detail the exact chemistry to be installed on your project. We recommend you always get written quotes from any contractors as there is a wide range of products on the market and not all of them are of the highest standards. We will also provide any data sheets available for the products and a link to the manufacturers website for your complete research.

 

10. How do you test for moisture in the concrete? 

It is crucial to measure moisture below the surface of the concrete slab. Some tests are surface-based and do not give reliable data points. For example, the anhydrous calcium chloride test measures only the moisture vapor emission rate coming from the slab’s surface. It tells you nothing about the moisture condition deeper inside the slab. Likewise, surface contact meters are ineffective in providing reliable information about the relative moisture gradient throughout the concrete. Any testing should comply with ASTM F2170. 

 

11. What is the most important part of the coating process?

Proper prep of the concrete is critically important. In fact, this one step can make the difference between a successful, long term application, and an application which fails prematurely. Proper prep involves more than just cleaning the concrete surface. Power washing wont work! Best practice usually involves a full grinding of the concrete, or shot blasting the surface. Either process will create a suitable profile while improving the surface porosity in preparation of the concrete. Look for a CSP of 4-6 at least. This will feel like medium grit sandpaper to the hand.

 

12. Do you carry General Liability Insurance?

Yes. We believe that is is important to protect our customer’s property by carrying General Liability Insurance. Homeowners insurance may not cover damages caused by contractors.

 

13. Do you offer any warranties on your work?

Yes! We do offer a written warranty on our work. The warranty is dependent on the chemistry/package applied and will be detailed in our written quote provided with each project. We also provide a warranty document at the completion of the project.

 

14. Will the epoxy have any issues binding to areas which have oil saturated into the concrete?

If there is oil saturated into the concrete, a standard epoxy (BPA) will not properly bind to these areas. The oil saturated concrete needs to be properly treated with a primer (typically BPF) to provide proper coating adhesion for long term durability. Since oil can over time deeply saturate concrete, it is not easy to remove the oil by grinding or use a “degreaser” for proper adhesion. We will use an oil stop primer on areas which have oil saturation.

 

Where Art Meets Chemistry