Many of my clients have asked, “Do I need to seal my natural stone, cement, or brick pavers, etc.” Anyone looking into their options concerning hard surface sealers eventually finds that the universe of sealers is not only vast, but can be expensive, confusing and down right irritating. Especially when you want to make the right decisions to protect your investments. I hope the following will clear some things up for all of you. If all else fails, ask an expert at Surface Solutions.
There are about seven competing technologies available to choose from when considering a sealer. For the most part, think of structural or penetrating sealers as different from topical or vertical surface sealers, each having their own pros and cons, and purpose. Choosing the right sealer will lengthen its longevity, improve maintenance, and cost much less over time.
Silanes, silicates, siliconates, siloxanes, silicones, acrylics, and polymer resins. The first three are considered penetrating sealers (more expensive and usually worth it) and the last four are more “coating based” and should be reserved for vertical applications. In the interest of everyone’s sanity I will focus on the penetrating sealers in this two part blog post.
Silanes – In short are penetrating sealers that soak into the concrete and do a fairly good job of sealing. However, the concrete must be saturated heavily with a high solid silane to achieve long life. Silanes have significant draw backs to consider the main of which is its hydrocarbon base and the possibility of changing the color or darkening the concrete or other porous surface. What this means is, a spill of another hydrocarbon such as oil, transmission fluid, gasoline, diesel fuel, or or similar products can result in a stain that permanently attaches to remaining active chemical chains in the sealer, producing a permanent stain in the concrete that can never be cleaned except through removal of the concrete. This makes silanes less attractive for stain resistance and a bad idea for garages and shops.
Silicates – Another penetrating sealer for concrete and other porous surfaces such as natural stone. Silicates work by creating a chemical reaction with the excess CaOH (Calcium Hydroxide) in the concrete that permanently binds the silicates within the concrete making them far more wearable and water repellent. Silicates are popular because they are permanent and do not require maintenance applications over time. The concrete must be worn away or removed to remove them. Most silicates are a very small molecule, which means they must be built from the “bottom up/inside out” in the concrete. They seal by going very deep and that usually means you will have to use more sealer to build up if you want any topical protection. These are commonly used to deter or stop the deterioration of cement coping damaged by salt water pools or deteriorating natural stone tiles in a wet environment.
Siliconates – This kind of penetrating sealer also significantly reduces porosity in concrete, natural stone, and other cementatous surfaces. Like the silicates they seal by forming a permanent chemical change in the surface, dissolving calcium hydroxide, reacting with it and other alkalis to form a new – nonsoluable chemical structure. They are usually a larger molecule, offering more surface protection. These sealers are great water proofing agents and will usually bead water quite well, and they will continue to resist water for years there after. Because they are larger molecule, they usually can be spread farther saving time and money. If done right, Siliconate concrete and stone sealers make an excellent call when your primary concerns are reducing moisture, freeze thaw or other damage, and staining.
Stay tuned next month for more exciting information on the other four “topical” types of sealers and their oleophobic (oil repellent) properties.
And be sure to check out our ad in the new Santa Barbara Axxess book, which can also be seen under “Home Maintenance, Remodeling & Movers” in the S.B. Axxess directory. As an Axxess member you not only save $$$ on restaurants, films, and theme parks, but you can also save 25% on your first Surface Solutions service until the end of the year.
Until next time, Have a GREAT Thanksgiving.