Your concrete driveway, sidewalks, and garage floor are all expensive components of your paved lifestyle. While we tend to think of concrete as virtually indestructible, Mother Nature smirks at our ignorance. She can destroy anything we build, and concrete is no exception. Just give her a few winters to ply her trade on your unsealed concrete, and you’ll see. Her freeze/thaw cycles will slowly crack the concrete, then more rapidly eat at it once the first cracks have formed. Be prepared to thwart her demise of your concrete before winter arrives with concrete sealing.
Water, Ice and Porous Surfaces
Concrete appears pretty solid, but in reality, it contains an entire system of pores and capillaries into which water seeps. In warm temperatures, this is no big deal. The water soon evaporates or, if it’s very porous, soaks on through. However, when the first snowfall melts on concrete and then freezes, it expands. Since concrete has no tensile strength (it isn’t pliable or bendable like, say, rubber), the ice pushes out in all directions, breaking up the paste (the binding surrounding the rock/gravel aggregate). Eventually, small, invisible cracks become large canyons for ice to form, further destroying the integrity of the concrete. Salt and de-icing sprays, whether applied on the slab or tracked onto it from vehicles, also eat away at your concrete paste. Spalling occurs when the top layer of paste breaks up exposing the aggregate below.
How Concrete Sealing Preserves the Slab
A good, professionally-applied concrete sealer coats the surface of the slab with a water-resistant/repelling substance. Applied as a liquid, it soaks into the uppermost pores as would water then hardens to form a barrier. Mother Nature is foiled at last. Types of sealers include:
Seal Before Winter Strikes
Like exterior house paint, concrete sealers need a minimum temperature during and after application in order to set and function properly. Most sealers require a minimum of 50 degrees Fahrenheit. The concrete itself must be at least the minimum temperature, as well. If a sealant is applied in colder ambient temperatures, it may take on a white hazy appearance and delaminate. It’s a good idea to schedule with your contractor as soon as possible before their schedule fills up.
Make Sure You Hire a Pro
Depending on the sealer that you determine is right for your application, sealing your concrete yourself could be a good DIY project if you have time. But make sure that you have all the right tools and are willing to be very thorough with the clean-up while also having a place to store everything for future use. While many sealants can be applied with paint rollers, the spray-on method provides a deeper penetration and longer-lasting seal.