Concrete surface preparation is one of the most critical components in a decorative concrete installation process. It is obvious that decorative coatings will adhere better to a clean surface than one contaminated with oils, glue, dirt, previous sealers etc. However, prepping also opens the pores of the concrete allowing coatings to penetrate deeper into the surface. Proper cleaning and preparation before installation will also prevent inconsistencies and flaws in the surface coatings over time.
There are several methods that can be used to prepare a concrete slab for decorating including sand blasting, diamond grinding, steel shot blasting, etching compounds and more. An effective, albeit expensive alternative to these is carbonic ice blasting. Dry ice blasting is not as widely recognized in the concrete world for its ability to prep surfaces, but can be just as efficient.
How it Works: Dry ice is a pure, solid carbon dioxide that doesn't melt. To make it, carbon dioxide must be converted from a gas to a liquid. Then, as the liquid CO² is exposed to normal air temperatures some of it freezes into a snow. This snow is pressed into small ice pellets or blocks, which are then used in dry ice blasting machines.
Using an air compressor, the ice pellets are blasted onto a surface at high speeds to strip a variety of coatings. As the pellets meet the surface, they go through a process called sublimation, transforming immediately from a solid to a gas and expanding up to 800 times their size. The expansion of the gas allows the particles to penetrate deep into the surface, while the incredibly cold temperature freezes and weakens grime's grip on the surface. With such deep infiltration, decorative products are able to adhere better to the concrete surface, increasing the durability of the coatings.
Advantages: Because the pellets immediately sublimate upon contact with the surface, the process is non-abrasive and there is minimal clean up. There is no dust or chemical residue to dispose of, unlike when using sand blasting or chemical strippers. The process is non-toxic, making it user friendly and safe for the environment and the high pressure can reach places brushes and chemicals sometimes can't. Dry ice blasting is a time saving option; blasting will leave the surface completely dry so there is no wait time between prepping and applying a decorative coating. At -109° Fahrenheit the dry ice is also able to kill mold and bacteria, making it a disinfectant and an excellent cleaning solution, even on walls stained with products like graffiti.
Depending on the dry ice blasting machine used, the unit may be entirely self-contained. Some machines do require a compressed air source. Most blasting machines are available to rent or purchase, with the option of paying a professional to come and do the work for you. One of the limitations of this technique, in lieu of pressure washing, sand blasting, or other preparation procedures is the expense. Cost for dry ice blasting your concrete can cost anywhere from $1.50 to $2.50 per square foot. Depending on the location of the job site and the availability of a machine and dry ice in the area, renting can be around $1,500 a week. Dry ice pellets used in the machine, again depending on the location, can cost about $.30-$.40 per pound. Buying a machine can cost anywhere from $12,000 to $40,000. However, if you're saving time and money and achieving better longevity in your concrete coatings, the initial expense might be worth it in the long run to you and your customers.
The Different Types of Cladding Used In Construction Home Renovation Services Why Should You Use A Residential Architect? Garage With Apartment: What Are Its Benefits Whom Will You Consult on Home Extensions and Renovations?
It seems like this method of cleaning has so many more uses than is given credit for! I'm thinking about getting dry ice blasting for my driveway. Hopefully all the stains can get cleaned too!
ReplyDeletehttp://www.301environmentalinc.com/dry-ice-blasting/