Tag Archives: concrete

Acid Etching Concrete Sport Surfaces

Sport and game courts are as popular as ever, especially with the extreme growth of sports like pickleball and continued popularity of basketball, tennis and multi-sport games and courts.

SportMaster has a multitude of durable and vibrant acrylic surfacing systems that are designed for asphalt or concrete courts.   Each substrate has a somewhat different approach to preparation, prior to application of the sport surfaces.  We are going to discuss a common step that is required when coating concrete courts for the first time.  This process is called acid etching or acid washing.

What Is Acid Etching? | Concrete Court Surfacing

Acid etching is the process of pouring a mixture of water and acid on a fully cured concrete slab.  Generally, either muriatic or phosphoric acid is used, but muriatic is a bit easier to find.  In a nutshell, acid etching promotes an ideal environment for chemical bond of coatings to concrete.  If done properly, acid etching only has to be performed once.  If a concrete slab has not been acid etched or coated, even years after it was built, it’s always a good idea to do it.

What is acid etching?

Why do I Need To Acid Etch My Concrete Court Surface?

Concrete goes through a chemical curing process after it is poured. It takes 28 days for a concrete slab to completely cure. There is a good bit of water in the concrete mix and as the concrete is curing, water is continuously wicking and evaporating upward and out of the slab.  As the water is migrating upward, it brings efflorescence, or salts, that reside in the concrete.  After the initial curing phase is complete, there is a crust of efflorescence on the surface of the concrete.

Lesson In PH & Surface Chemistry

PH, or “potential of hydrogen” is the scale of acid vs base.  The PH scale goes from 0 to 14, whereas 0 is very acidic and 14 is very basic (alkaline).  For ideal chemical adhesion, coatings prefer a neutral environment.  This would be 7 on the PH scale.  When concrete cures, the surface crust or salt deposits, are very high in alkaline (a PH around 13.5).  The process of acid etching neutralizes the high alkaline crust and brings the surface PH back to neutral.  The acid washing process also helps to break down and rinse away the powdery efflorescence.  This also prevents flaking or peeling of coatings & migration of powder into the color coatings resulting in a cloudy appearance.

Concrete Sport Surface PH

How To Acid Etch A Court | Pickleball – Basketball – Tennis

In this section, we will outline how to acid etch a concrete court surface.  But first, here are a few pointers:

  • Make sure to acquire and wear adequate safety gear, when working with acid.  Thick rubber gloves, safety glasses, and relevant clothing and boots.  Avoid breathing in the direct fumes of concentrated acid and ensure that you have plenty of air flow when inside.
  • As a general guideline, it should take around 2 to 3 gallons of acid to etch a smaller court, like a 30′ x 60′ pickleball court & around 8 to 9 gallons for a full tennis court (60′ x 120′).
  • Protect any sensitive plants or surrounding materials around the border of the court.  Even though you will be rinsing off acid that is very diluted and has already reacted with the surface, it’s a good idea to minimize contact as much as possible.

Step 1:  Spray water on the court to dampen the surface.  This helps the mixed acid and water to flow and better penetrate the surface.

Step 2:  Properly mix the acid and water, following the dilution measurements on the acid bottle.  There should be directions for “masonry etching” on the bottle instructions.  Remember to fill the empty bucket with water first and then pour the correct amount of acid into the water.  This helps to prevent splashing of acid.

Pouring Acid Into Water

Step 3:  Pour the acid & water mixture onto the concrete, working in small areas or sections at a time.  If you’re able to have a helper, have the 2nd person immediately broom the solution around with a push broom to make sure the acid comes into contact with every square foot of concrete.  Make sure that you don’t pour the acid mixture and expect it to span a long distance.  Instead, pour around a small zone in a tight “s” pattern to ensure direct contact with the surface.  Since the acid mixture reacts instantly with concrete, the potency diminishes as it spreads.

Pouring and Brooming Acid Concrete

You will notice a cloudy appearance in the liquid and minor bubbling reaction, which means the acid is working to neutralize the surface salts.

Acid Neutralizing Concrete

 

Step 4:  As you move on from section to section, you will notice the reaction dissipates in the previously treated area.  At that point, you can rinse those areas off to flush surface contaminants and  move the neutralized acid solution off the court surface.  If possible, it’s best to start on the high end of the court and slowly move all of the water toward the low end of drainage.  If possible, try to keep the entire court damp throughout the process, which keeps the sediment from sticking to the surface.

Step 5:  After you have etched the entire court surface, and rinsed away most of the remaining acid mixture and sediment, it’s always good to do a final rinse of the entire surface.  This ensures a completely clean surface, free to any potential acid or other contaminants.  If you’re indoor and don’t have available drains, a floor cleaner machine can be used for a good final cleaning.

Rinse Surface Clean Water

*Remember to protect and avoid adjacent concrete areas that are not receiving the sport coatings, as the acid can create a different color or appearance to exposed concrete.  This is hidden when coatings are applied over the acid etched play areas.

Acid Directly On Concrete

Common Misconception About Acid Etching

Many people think that acid etching creates a physically textured surface for the coating to adhere.  This is not the case, as the actual purpose was established earlier in this bulletin.  It is still very important for the concrete surface to have a medium-broom finish or similar.  That is very important for physical adhesion of coating systems.  Remember, the two most importance factors for good adhesion of sport coatings is:

  • A good surface texture/profile for physical adhesion
  • Neutral surface PH for excellent chemical adhesion

 

Can Pickleball Be Played On A Tennis Court?

Pickleball has become one of the fastest growing sports in the nation.  The demand for places to play Pickleball leads to the question, “Can Pickleball be played on a tennis court?”  

Yes, Pickleball can be played on a tennis court surface, and we will discuss some great options to keep Tennis and Pickleball players happy.

Blended Pickleball Lines On A Tennis Court

A common trend, that is working well, is to maximize the current “real estate” of existing tennis courts.  That is usually a “win-win” and has been done for years with tennis and basketball court combinations.  By USTA and ITF rules, tennis court lines must be white.  Pickleball court lines can be added in a different color, so that tennis or pickleball can be played on the same court (at different times, of course) and the eye can focus on the applicable set of playing lines.  As with the USTA’s kids tennis program known as 10 & under tennis or Quickstart, it is usually recommended to paint the Pickleball lines in the same color family as the court surface color. To better explain, if the court color is blue, apply the Pickleball lines in a shade of blue that is lighter or darker than the surface color. This makes the lines less distractive to tennis players.

How Much Does It Cost To Add Pickleball Lines To A Tennis Court?

This is a relatively inexpensive process and is usually performed by a qualified tennis court contractor.  It can range anywhere from $250  to $600 per court, depending on a variety of factors:

  • Existing surface condition (how much cleaning and prep is needed in order to get the new line paint to adhere properly)
  • Total number of Pickleball courts to be painted (better price per court, for multiple applications to minimize mobilization)
  • Lower cost to apply the Pickleball lines as the tennis courts are being resurfaced.

To get a free estimate from a qualified Pickleball court contractor on your facility, contact us and we can put you in touch with an experienced installer.

Pickleball Court Construction | Permanent Pickleball Courts

There is also a boom of permanent Pickleball courts being installed in park districts and residential settings.  Since Pickleball courts are smaller (44′ x 20′) than tennis courts (60′ x 120′), more and more avid players are building backyard Pickleball courts.  It is great fun for families, kids, and older players alike.  In fact, many older players that are unable to physically handle tennis are turning to Pickleball for fun and fitness.

Pickleball court construction utilizes the same construction methods as tennis and basketball courts.  Generally they are comprised of an asphalt or concrete substrate, and then surfaced with a non-slip, textured SportMaster brand of acrylic surface.  Here are some additional resources for Pickleball court construction, surfacing, and striping layout:

  • Pickleball Court Surfacing Specifications – Asphalt
  • Pickleball Court Surfacing Specifications – Concrete
  • Pickleball Court Striping Layout & Dimensions – Diagram

 

 

What causes bubbles or blisters on a tennis court surface?

Bubbles and blisters on a tennis court surface, or other coated sport surface, are fairly common.  This is usually a result of improper tennis court construction or malfunction of the drainage system. When sub-surface water becomes excessive and is not properly drained away from the court, it can breathe through the slab in a vapor form and create hydrostatic pressure under the coatings.  This pressure builds more in weaker surface areas and creates a blister or bubble.  When the blister is raised, water vapor stretches the coating film and slowly breathes through to escape.  After most of the water pushes through, blisters usually lay back down and disappear until the next rain or precipitation event.  It’s important to note that excessive watering (sprinklers) around the court edge can also lead to blistering problems.  That being said, it’s very important to minimize accumulation of water beneath the court slab.

bubbles blisters pickleball court surface
Bubbles or Blisters on Court Surface

How Do I Get Rid of Bubbles and Blisters on a Tennis Court Surface?

In order to take care of the bubbles and blisters, long term, you will need to do some investigating.  Start by making sure any and all drains around the tennis court are free of debris or anything that would prevent proper flow of drainage water.  You may want to enlist the help of an architect or excavation professional in order to evaluate the current drainage system and see if it was installed properly, or at all.  If the court substrate is concrete, you must ensure the following:

  • Was a vapor barrier installed beneath the court when poured?
  • Are there perimeter drains that can take the water away from the court when it runs off after a rain? (Important that water is intercepted on all side of the slab, to prevent water beneath the court)
  • Was the concrete allowed to cure for 28 days, prior to coating?
  • Was the concrete surface acid etched to neutralize the alkalinity and balance the PH?
  • Were any curing compounds used on the concrete?
Court Surface Edge Drain
Surface-type drain – good for the low court edge

 

 

 

 

 

The American Sports Builders Association (ASBA) maintains construction guidelines for asphalt and concrete tennis court and sport surfaces.  Ensure that the construction of the court meets their guidelines and find out from the tennis court builder if they followed the ASBA recommendations.  This may help you figure out why the blisters are occurring.  If you are still not sure what to do, feel free to fill out the contact form on this page and we can put you in touch with a SportMaster recommended, tennis court builder.  They can perform a free site visit with you and provide feedback and estimates for repair, resurfacing, or re-construction. You can view our Engineering Specification for Athletic and Recreational Surfacing on our SportMaster site.

Tennis Court Blisters
Tennis Court Blisters

How Long Does Tennis Court Crack Filler Last?

Question: How long does tennis court crack filler last?

Answer: Cracking of asphalt and concrete pavement surfaces is a common problem. Even if the asphalt or concrete is properly built, there are still variables beyond the control of the contractor and crack filler producer.

There are different reasons for pavement cracking, but a majority of the cracks on concrete and asphalt courts are structural. This means that the cracks go completely through the pavement layers, into the base of the tennis court.

Acrylic tennis court crack fillers are designed to fill and seal off the surface of the crack. This is designed to minimize water and moisture flowing into the crack and stone base of the court, and slow down degradation of the court through further cracking. The main problem is that once a structural crack opens, there are two separated slabs of pavement constantly moving back and forth. This expansion and contraction happens daily, depending on temperatures, moisture, and other environmental conditions. That being said, cracks that have been filled may open within days, weeks, months, or years of application. An Acrylic crack patch is an ideal solution for this common problem.

Pourable Tennis Court Crack Filler
Pourable Tennis Court Crack Filler

Even though we offer some elastomeric acrylic crack fillers, the degree of movement in the crack determines how long the product can perform before breaking open or pulling away from one side of the crack. Frequency of moisture, freeze-thaw, and various climate conditions are other factors that play a role in longevity of crack fillers and repair.

Crack filling is a maintenance role. The best way to maintain a tennis court crack is to fill it whenever you see it open. A good rule of thumb is to check the court(s) over in the spring and early fall (when temperatures are not getting below 50°F or 10°C) and perform necessary crack filling to extend the life of the facility. Many sport surfacing contractors also offer maintenance programs, where they make spring and fall visits annually, and advise court owners of needed crack repairs, resurfacing, or other issues.