If the finishing personnel were to float the entire slab by hand just before stamping, they would break the crust and the surface would have the same consistency as the concrete underneath. Crusting cracks would be greatly reduced.
This process requires getting out on kneeboards, which takes more time and effort and could delay stamping operations. Unfortunately, if he has already begun stamping it is likely that antiquing release agent has already been applied.
If he is using liquid release, he can stop stamping, re-float the surface, and wait until the slab is truly ready to stamp. To keep the surface from crusting in the first place, chemicals such as evaporation retarders are often used.
Evaporation retarders not to be confused with surface set retarders , are liquids sprayed onto the surface of the slab after each bullfloating. These chemicals form a thin film which keeps moisture from evaporating too quickly. They allow moisture to stay in the concrete and help even out the set. Confilm from BASF is one such product. There are several ways to deal with crusting cracks.
The first is to repair them while stamping. To do this, the stamper carries a 3 inch paint roller with him as one of his detailing tools. The same thing occurs when concrete dries too fast from the top down. Remedies for reducing surface crusting include using admixtures to slow the concrete set time, using surface evaporation retarders, avoiding darker colors, and scheduling the concrete pour for the coolest time of the day.
Using stamping tools with deep grout lines, such as random stone and large slate patterns, can aggravate the cracking problem. One way to repair these small cracks is to use a colored cement paste, or color patch. Some color hardener manufacturers offer these patches in their standard color palette for use in filling and repairing these types of cracks and small popouts. Some contractors will sift the sand out of the color hardener they are using on the project and use this to make a color patching material.
I recommend wetting color patch materials with a blend of concrete bonding polymer and water. Use a wooden tongue depressor or gloved finger to smear the color patch into the cracks. Soften the edges with a damp rag or sponge to blend the patch and color into the slab. Let these repairs cure for 24 hours. Find Crack Repair Products.
Find Stamping Products. Can I tint a clear liquid release agent to add color when stamping concrete? If so, how is it done? You will be hard pressed to find any official written guidelines on tinting a liquid release, but that doesn't mean it can't be done. Most manufacturers of liquid release don't publish any guidelines because the process is more art than science, and each job will present different conditions and color requirements.
Achieving success requires practice, experience, and some experimentation. The most common tinting method is to add a colored release powder to the liquid release and then shake the mixture well to disperse the color. A ratio that has worked well for me is 2 to 4 ounces of dry color for every 64 ounces of liquid release.
Although many applicators have had success with this method, it takes practice to know just the right amount of tinted release to apply to prevent the stamping tools from sticking to the concrete. Apply too much release, and you get a puckered, spongy mess. Apply too little, and you get pulling and tearing of the surface. Some applicators have better success stamping the surface first using a clear liquid release and then applying a tinted liquid release immediately afterwards to highlight the texture of the surface.
This method tends to work better with more porous surfaces, like stampable overlays. How do I identify the cause for this? I live in eastern Pennsylvania, and we've had typical winter weather.
Surface failure of concrete is usually caused by one of two reasons: The concrete was placed or allowed to cure during freezing temperatures or the concrete was finished improperly.
If concrete freezes during the curing process, the chemical process that develops strength is stopped and you end up with soft, crumbling concrete.
There is no fix for this; the concrete needs to be removed and replaced. Get tips on dealing with spalled concrete in patios, driveways and other concrete surfaces. Expert advice on why spalled concrete occurs and how to fix it.
See a demo on the repair process. This weak surface is more susceptible to typical winter freeze-thaw cycles that can cause surface failure like spalling. Deicing salts applied to the driveway or dripping from vehicles parked on the driveway only speed the process of freeze- thaw destruction. Applying a good sealer will help prevent or minimize these issues, but only to a point.
If the integrity of the concrete is suspect, there's not much you can do to stop the surface destruction. Once the top of the concrete is exposed, you have "opened the lid" so to speak, and year after year exposure to the elements will continue to eat into your concrete.
An overlay to cap the concrete or removal and replacement may be the best remedies. Did you get a warranty on your concrete? If so, talk with the installer about your options. We just got a new swimming pool installed, along with a stamped concrete deck.
But the stamping created painful ridges, making the surface so abrasive to walk on that I have to wear shoes just to get to the pool. It even tore off two pads from my dog's feet. I was expecting the texture to be like other concrete walkways, but it's like sandpaper. Now I have 1, square feet of walkway that I can't really walk on in bare feet.
How can this pool deck be smoothed so I can walk on it comfortably? Would grinding, polishing or sealing work with a stamped pattern? Too "ruff" for me!
When a new stamped surface is abrasive on bare feet,it may need to be ground prior to sealing. The pattern used random stone is one of the most aggressive available. The picture does not show enough detail, but depending on surface smoothness prior to stamping, you can get different levels of roughness.
You have a very new slab, so I suspect that a sealer hasn't been applied yet. A period of 28 days should pass before application of a decorative sealer. Applying a couple of light coats of a low-solids acrylic sealer will help alleviate a bit of the roughness, as well as bring out the color. Test this in a small area first. If a sealer doesn't do the trick, a walk-behind sander or buffing machine with a black rough-bristle pad will take off the rough edges and soften the surface.
Again, test this method first in a small area. What caused this stamped overlay on a patio to fail? While this is quite a devastating situation, and will cost both time and money to repair, the cause is quite simple and direct. In most decorative overlay projects, surface preparation should cost more and take longer to perform then the actual overlay installation itself. Creating a profile or degree of roughness of at least 6 on the International Concrete Repair Institute ICRI surface preparation scale is mandatory for successful adhesion.
The surface needs sufficient "bite" for the overlay to bond, otherwise delaminating failure can result. As can be seen in the picture, the surface under this overlay is smooth, with little to no profile. Unfortunately, not much can be done to save this patio overlay.
I am worried about cracking as it will be about 20 x 30 feet. One contractor said something about saw cutting to prevent cracking but two others didn't. I don't even know what "saw cutting" means. I don't care if it's stamped concrete or not as maybe I don't know all the new techniques for getting this look. I want it to look like stone or brick but I don't want stone or brick since we just tore out a small brick patio as we were tired of dealing with weeds growing up between the bricks.
How can I get a gray colored, stamped look but not worry about cracks? Valerie: The geotextile plus the polymeric sand very important helps a lot. I also use round up on everything at the beginning of spring just to be sure paranoia. Concrete probably is still lower maintenance overall than pavers. You do have to reapply polymeric sand every few years. Concrete does, however, crack and it is hard to replace the cracked pieces without replacing everything.
With good expansion joints, and a tolerance for minor cracking this might be a good option for you. In our area, stamped concrete is a lot cheaper than pavers. If I had to do it all over again which is not going to happen anytime soon , I would consider the paver decks. It appears that there would be no weed problem since they are elevated.
No cracking and basically no maintenance. Stamped concrete patio. Ugly stamped concrete patio. Concrete everywhere cracks eventually. Some places faster than others. The sawed areas are designed to help manage where the cracks occur. I am more of a paver person with weed control provided by a geotextile under the pavers and polymeric sand between them.
Sootsprite - I love your patio! Thanks for the photo. I will show it to the companies who are bidding the job. I like the pattern and the texture. Smit that worries me! Does the geotextile stuff completely control weeds? Makes me wonder if we should rethink what we use. Our biggest needs are that it be as maintenance free as possible and last 30 years. That's why we got rid of the deck. Tired of the powerwashing and staining. We live in Kansas City so very hot in the summer and can get very dry.
We water the foundation in the summer so it doesn't crack. But it's also guaranteed to get below zero for several days each winter too. Does anyone use 'rebar' to help control the cracking? I hope I spelled it correctly. The saw cuts are a minimum but my contractor also used a lot if rebar. I've never seen pavers used for a deck --gorgeous! I'm going to show it to my husband.
It is really beautiful but I bet he'll be worried about the weight, the cost and possibly even wood rot in the framing system underneath over the long haul. But I like to know all the options! Thank you!
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