SEALING DECORATIVE CONCRETE—THE GOOD, THE BAD, AND THE UNDECIDED
Picture this: your Great-aunt Emma running naked through heavy traffic in downtown Manhattan. Let's face it, some things are better off covered and won't last long if they aren't.
The same goes for outdoor decorative concrete projects. Left unsealed, the colors will fade, water marks may be an issue, and stains can penetrate leaving ugly oil spots where the service guy left his old jalopy parked on the driveway. It's pure and simple, the job just won't last without a good sealer.
But in a tight economy where every penny counts, is sealing outdoor decorative concrete jobs worth it to your customer? Let's take a look at some of the issues.
It's true, sealing an outdoor decorative concrete job will add to the cost of the project. A good, reliable brand of concrete sealer isn't cheap. Add to that the cost of prepping the surface and applying the sealer and you've raised the price quite a bit. Your job is to help your customer understand they've made a substantial investment in their decorative concrete and it needs to be protected.
Sealing an outdoor decorative concrete project is the best way, and as far as we know the only way, to minimize color changes from the sun's UV rays. An unsealed, decorative stained concrete surface will show faded colors in a matter of a few months. You could advise your customer that's what happens with an unsealed project and let them make the decision about sealing, but rest assured that an “I told you so,” from you when the fading happens will not comfort them. Earned or not, you will get the blame for a poor job, and negative comments will hurt your business. Often showing them a touchable example (not just a picture) of the added depth of color that occurs when decorative concrete is sealed is enough to convince them that sealing is the way to go.
We all know that time is money, so there's a real temptation when you're bidding a job to cut as much labor expense as possible. Simply eliminating a sealer, cleaning the concrete, and calling the job done is a tempting way to cut costs, and it allows you to move right on to the next job. It also means the customer can use their space sooner for the big barbeque they have planned. Just expect an angry call from the customer when their new unsealed patio now has purple circles from spilled wine, or stinky, brown stains compliments of the neighbor's St. Bernard.
The upside of sealing an outdoor decorative concrete surface is the ease of maintenance. Dirt and dust are easily hosed off the surface, and spills wipe right up, leaving the surface unaffected. Customers like that idea. The downside of sealing an outdoor decorative concrete surface also involves maintenance. Concrete must be resealed periodically. Customers don't like that idea. As for you, the contractor, resealing simply means more business.
Concrete has enemies. Mother Nature pounds the surface with rain or snow, then sends in freezing temps. An unsealed decorative concrete surface allows water to penetrate the pores of the concrete, and the vicious freeze-thaw cycle does its damage. And who knew the movers would drag a heavy crate across the unsealed surface, leaving huge scratch and scrape marks? A good sealer stops water penetration before damage happens and protects the decorative concrete job from abrasion--just what your customer wants to happen.
There's no denying that sealed concrete can be slippery when wet or greasy. A responsible contractor should always use a slip-resistant additive when sealing outdoor pedestrian surfaces that may be exposed to wet, oily or greasy conditions. OSHA and the American Disabilities standards for slip-resistance are available on our website. In the case of sealed concrete surfaces, safety is an easy and inexpensive fix, so skipping the additive shouldn't even be an option. While unsealed projects aren't as slippery, they also don't get the positive benefits of sealing we've talked about earlier in this article.
So, to sum it all up, there are arguments for and against sealing outdoor decorative concrete. We recommend sealing. But in the end, it's your job as a contractor to work with your client to figure out what's best for both of you. Whatever you do, do it in good conscience.