Sealer Problem

[joe]

Maybe someone here can help me. I have a concrete brick driveway that I have been sealing with an acrylic sealer every year for the last 10 years. The bricks now are grey, how do I bring back the natural color again? I have attached a picture of the problem. PLEASE HELP!

[Paver]

You have too much sealer on your pavers and the acrylic is starting to "lift". Just like a wood floor, eventually the sealer needs to be stripped when too much builds up. Check with the sealer manufacturer to obtain stripping instructions, but here are some general stripping instructions. The whole process is very messy. You will need to get your hands on a large amount of gel-type paint stripper. Try to avoid working in direct sunlight, work on a cloudy day, early a.m. or later p.m. Tape plastic over any adjacent painted surfaces such as door, siding or thresholds or any exposed building materials. Barricade paver area to be stripped. With water, thoroughly saturate adjoining lawn and planting areas. Try to keep pavers as dry as possible. Wearing eye protection, rubber gloves and rubber boots, pour paint stripper onto the pavers while walking around trying to get equal amounts over the treatment area. Work small areas (100 to 400 sq. ft.) at a time. Do not let the stripper come in contact with any asphalt. After making sure all sealed areas have stripper on them, evenly squirt dish soap (like Dawn) over the area. Do NOT let materials dry. Using a stiff bristle (nylon or plastic) street broom, start pushing broom in one direction around the perimeter, walk in circles around the driveway moving closer to the center with each pass. Do NOT use any sweeping action or broom back over the swept area. Let the broom spread the stripper evenly. Do NOT let materials dry. Wait about 5 minutes until curdling or bubbling stripping action begins. Do NOT let materials dry. Using a garden house with a spray nozzle, wet down (mist) the area with water to create a slurry but not too much to cause a lot of water to flow off the area yet. Using a squeegee, broom or flat shovel, capture slurry mixture and contain it. Use a large funnel to put stripped materials back in original cans for disposal. Starting near the house and using a pressure washer (1500 to 3000 PSI), slowly work back and forth over the pavers to rinse the remaining stripper and sealer toward the far end of the driveway for containment. Once completed, dispose of waste materials according to government regulations.

You may need to repeat this process a few times until desired results are achieved. Once you have stripped off as much of the acrylic as possible, you should be safe to seale the pavers again. In the future, if the sealer you use has enough solids in it, you should be able to bring the shine back by spraying a light coat of solvent such as toluene or xylene on the pavers. Again, check with the sealer manufacturer to obtain their specific stripping recommendations.

[Glenn W]

Sounds like acrylic sealers are not worth the trouble. What other sealer options are out there?

[Kings Dry Treat Sealers]

We have a sealer for all natural or manmade stone surfaces that gives a written 15 year warranty against any staining when applied by an accredited applicator. i.e. no more oil stains on paver or concrete driveways, no more efflorescence or mold. Can be used on inside as well as outside.

[Valueguy]

I live in Florida. My driveway is Charcoal and dark Red concrete pavers. They have been sealed 6 times over the past 5 years using H and C solvent based "wet look" (Clear 23) sealer.

It seems the sealer lasts only 4-6 months before the pavers start turing a little grey. When I reseal the color returns. In the winter months the sealer lasts 6 months. In the summer I am lucky to get 3 months. The weather here is brutal with lots of rain and temperatures in the high 90's (I bet you could cook an egg on the concrete).

Should I be concerned about Acrylic build-up? My plan is to start using Toluene instead of sealer every few months until the "shine" no longer returns. I figure that the H and C has enough residual solids that I can get another year without recoating with sealer.

For those that think I have too much sealer should I use Xylene instead of Toluene? I read that Xylene will "cut" the acrylic and weaken it. So, over time all the H and C would wear off anyway.

Finally, should I wear a mask when applying the Toluene? Should I roll it to avoid "breathing in" the chemicals? When applying the H and C I have both back rolled and sprayed the product.

If and when I apply more sealer I am going to switch to PaverGuard over H and C. Comments?

[Paver]

You have too much of an acrylic build on the pavers from resealing so many times so often. An application of Toluene instead of sealer may help clear up some of the “gray”, but only temporarily. Unfortunately, you need to strip all the sealer from the pavers and start fresh.

In regards to your Xylene versus Toluene question, both solvents will work to re-emulsify the acrylic, but stick with Toluene. The problem with Xylene is that it could degrade the UV stability of the acrylic, causing it to yellow over time. The use of either solvent is not going to help the sealer wear away any quicker.

Lastly, I recommend using a sprayer (that is approved for use with solvents), it is much faster than a roller. Yes, you should wear a mask designed for solvent fumes and try to avoid getting it on your skin if possible.

[Valueguy]

I agree that my problem is a build up of acrylic on the pavers; but, it doesn't look too bad. In fact, when wet the paver looks great. It looks mostly dull now when dry but I do see some build up. My plan is to apply Toluene 2-3 times a year for the next 2-3 years. This will allow me to avoid the "messy" removal of excess acrylic. In addition, in my area I doubt any sealer can last for more than 2 years under rain, high temp and high humidity conditions.

I bet the Toluene will last several months with each application as the Sealer certainly did even with the build-up.

I have learned my lesson here but I don't plan on a messy removal when nature and time will do it for me.

[Valueguy]

Today, I applied 15 gallons of Sherwin Williams Toluene product to my pavers. I have 5-6 coats of H and C Solvent based Clear sealer on my pavers; as such, I thought this was my primary problem. Now, I think I was wrong.

I purchased every readily available solvent at Lowes and Sherwin Williams. I tried Xylene, Toluene (went with 15 gallon), Laquer thinner, Pain thiner, Methylketone, etc. but nothing really got rid of the "white stains" on top of my pavers.

But, I had a small sample size from Aldon Chemical called Efflorescence treatment WHICH WORKED LIKE MAGIC. All the other chemicals failed to get rid of the white scale build-up except the Aldon product. Of Course, they wouldn't tell me what was in the product.
http://www.aldonchem.com/


I suspect I have a combination problem on my pavers. First, too much solids on the top of the paver. The toluene helped dilute the solid. I now know that 7-10% solid is more than sufficient and the 20-25% solids in the H and C was too much (plus 5 coats). Second, the solids on the top of the paver were "blocking" or trapping the moisture in the paver. The moisture from below couldn't escape from the top of the paver causing the white buildup.
Somehow the Aldon Chemical "Efflorescence Treatment" was able to penetrate my H and C sealer and hide the white discoloration.

I don't know how long the effect will last. But, I do know that my sealer needs nature and time to really wear down so as to allow the moisture to escape from my pavers. I realize that a good paint stripper would allow me to just fix the problem right away but I have a 5,000 plus square feet driveway. I imagine the waste and cost to do this professionally would be enormous.

Any ideas? Comments on Aldon Chemical? Should I use their sealer next after a few weeks? The water still beads on my paver so I don't think another sealer is needed at this point.

The Sherwin Williams guy told me in about two years all the sealer should wear off. But, I want a "decent" looking driveway and am willing to spend $1500 per year.

Thanks for any input.

[Derek]

I apologize in advance, I have to leave my office in a few minutes.
I will post a proper reply as soon as I can.
I would like to discuss your pavement with you as several things that have occurred at your residence do not make a lot of sense to me...I also have some recommendations for you.

Our company specializes in cleaning and sealing brick pavers, concrete pavement and vertical masonry. No installation, just maintenance. We have cleaned and sealed millions of square feet of pavers in the Midwest.
You are definitely on the right track...but I may be able to help you further...

I will try to take some time tomorrow and respond to this thread.

[Valueguy]

You have too much of an acrylic build on the pavers from resealing so many times so often. An application of Toluene instead of sealer may help clear up some of the “gray”, but only temporarily. Unfortunately, you need to strip all the sealer from the pavers and start fresh.

In regards to your Xylene versus Toluene question, both solvents will work to re-emulsify the acrylic, but stick with Toluene. The problem with Xylene is that it could degrade the UV stability of the acrylic, causing it to yellow over time. The use of either solvent is not going to help the sealer wear away any quicker.

Lastly, I recommend using a sprayer (that is approved for use with solvents), it is much faster than a roller. Yes, you should wear a mask designed for solvent fumes and try to avoid getting it on your skin if possible.

I am FINALLY following your advice and the advice of AldonChemical in STRIPPING my old H and C sealer. The premium stripper from Aldon is working well but it is messy and a lot of work. In addition, I need a TON of stripper to get my whole driveway done. Aldon recommeends Lacquer thinner for clean-up after stripping the old sealer. I can buy Lacquer Thinner or Toluene from any pain store in 5 gallon drums. I plan on going with the lacquer thinner.

If after stripping and clean-up my pavers look good and bead water do I need to reseal them? What will another coat of sealer accomplish if water still beads? I will reseal if you recommend it.

[Derek]

I wouldn't use laquer thinner.
I have had some cause undesirable effects lately. I have used it a TON in the past...as a thinning agent for acrylic sealers...but putting it on straight may cause problems.

The stripper should be applied and allowed to work until it removes ALL acrylic. There may be some latent acrylic residue causing some hazy spots or streaks in areas after the stripping is complete (you should be able to feel the difference between the stripped areas (should feel "raw" like a bare paver) and the areas yet to be stripped). You should reseal the entire pavement after stripping. These latent acrylic areas will disappear when resealed.
I wouldn't waste the time or money on putting solvent on the pavement in between...it is an unnecessary step.

[Valueguy]

You have too much of an acrylic build on the pavers from resealing so many times so often. An application of Toluene instead of sealer may help clear up some of the “gray”, but only temporarily. Unfortunately, you need to strip all the sealer from the pavers and start fresh.

In regards to your Xylene versus Toluene question, both solvents will work to re-emulsify the acrylic, but stick with Toluene. The problem with Xylene is that it could degrade the UV stability of the acrylic, causing it to yellow over time. The use of either solvent is not going to help the sealer wear away any quicker.

Lastly, I recommend using a sprayer (that is approved for use with solvents), it is much faster than a roller. Yes, you should wear a mask designed for solvent fumes and try to avoid getting it on your skin if possible.

I used 17 gallons of paint stripper followed by a good power wash. Then, I used 15 gallons of lacquer thinner. Any ideas how many gallons of sealer I need or the project?

[Paver]

This reply is almost a month late, so you have probably figured out how much sealer you need, but if you are planning to spray on 1 coat, you will probably cover 160 sf per gallon.