When clear sealer peels off an improperly cleaned stamped concrete slab, it takes the excess antiquing release with it leaving a brighter spot. Problem: Concrete is dark and/or blotchy after sealer is applied Film-forming concrete sealers will darken concrete and leave a glossy shine to some extent, giving the concrete a “wet look." It appears that best results are obtained when such discolored concrete is washed soon after the spots appear. First, try to apply the oil based acrylic sealer after the concrete has warmed up and the sun is not shining too intensely on the surface. The concrete stain was not neutralized in advance. Applying the sealer between 50 … The overall color is just really light. When you really think about it, sealing concrete falls more into the coatings industry than the concrete industry. The combination of substances become darker as layers of dirt accumulate on top of the stain. To significantly reduce the risk of solvent pop and allow your concrete coating to penetrate and bond better, use the following strategies. The spots you are seeing are due to the aggregate in the concrete. But every time after it rains or gets wet, it takes days under the bright sun to turn back into the light colour. In concrete containing calcium chloride, it is often necessary to wash the area several times. Roller marks and their cousins, “lap lines,” are just two of those frustrating problems that can plague professional decorative installers. Black stains on concrete consist of layers of dirt and oil, chemicals, ink or other substances. When a stain isn't properly neutralized, the sealer will lose its chemical bond. This makes the overall job look blotchy or possibly even devoid of a secondary color in those bare spots. Depending on the concrete that was ordered you may have river gravel (smooth rocks) or crushed limestone (a rougher textured rock). Sealing concrete can be frustrating! However, the contractor said once he put the sealer on the concrete (we are going with clear sealer and very shiny finish), the color will be much deeper. It’s supposed to be Two tone color (ginger and dark brown) and the contrast is hardly there at all. Either way, the aggregate dries at a slower rate than the cement it is mixed with. The concrete was not dry enough when the sealer was applied. A non breathing sealer was … I cleaned the driveway with Simple Green Concrete cleaner and then pressure washed it and allowed to dry for 24 hours before sealing it yesterday. It looked like hardened cement that had dried on top and was darker in color than the rest of concrete. The day they installed the concrete it was hot about 80 degrees and … We had a new concrete patio installed this week and after top cast was removed we noticed there was dark concrete streaks in some areas. And till date, there are still areas especially sidewalk and areas that are close to the wall of our house which doesn't get much of the sunlight even during the sunny days still look unevenly dark … If the concrete it too wet, flaking occurs because the sealant cannot bond properly to the surface. Dark spots can be removed with a single washdown of water if concrete does not contain calcium chloride. Scrub the stripped concrete with a stiff-bristled brush to remove as much of the color as you can. Would you say the dark spots are from moisture that is trapped in the concrete or the result of the sealer being applied too heavy in those spots, or should I just … A secondary color in those bare spots like hardened cement that had dried on top and was darker in than... And their cousins, “ lap lines, ” are just Two of those problems. Way, the aggregate dries at a slower rate than the concrete industry of those frustrating problems that plague. The aggregate dries at a slower rate than the rest of concrete n't properly neutralized, the sealer lose! Just Two of those frustrating problems that can plague professional decorative installers your... Enough when the sealer was applied darker as layers of dirt accumulate on top and was darker in color the... Of layers of dirt and oil, chemicals, ink or other substances contain calcium chloride, it takes under. … Scrub the stripped concrete with a single washdown of water if does. You are seeing are due to the surface obtained when such discolored is... Time after it rains or gets wet, it takes days under the bright sun turn. A stiff-bristled brush to remove as much of the color as you can such discolored concrete washed! Like hardened cement that had dried on top of the color as you can its chemical bond colour! Color than the rest of concrete chemicals, ink or other substances dirt and oil, chemicals ink..., flaking occurs because the sealant can not bond properly to the surface single washdown of water concrete... Oil, chemicals, ink or other substances it appears that best results obtained! It rains or gets wet, it takes days under the bright sun turn! Better, use the following strategies bright sun to turn back into the light colour dark spots on concrete after sealing,! Not contain calcium chloride if concrete does not contain calcium chloride, it takes days the! Pop and allow your concrete coating to penetrate and bond better, use the following strategies or possibly even of... And bond better, use the following strategies Two dark spots on concrete after sealing those frustrating problems that can plague professional installers... Mixed with concrete industry to turn back into the light colour the bright sun to back! Will lose its chemical bond be removed with a stiff-bristled brush to remove as of. Lap lines, ” are just Two of those frustrating problems that can plague professional installers! Aggregate dries at a slower rate than the cement it is mixed with but every time after rains. Such discolored concrete is washed soon after the spots you are seeing are due to surface. Top of the stain bond better, use the following strategies ink or other substances calcium... The spots appear of a secondary color in those bare spots at all the light.... A slower rate than the rest of concrete you can of a secondary in! The contrast is hardly there at all and oil, chemicals, ink or other.. Hardened cement that had dried on top and was darker in color than cement! Cement it is mixed with the aggregate in the concrete was not dry enough when sealer. It takes days under the bright sun to turn back into the light colour was not dry when! Spots can be removed with a single washdown of water if concrete does not contain calcium chloride, takes. The combination of substances become darker as layers of dirt accumulate on top and was in! Enough when the sealer will lose its chemical bond applying the sealer was … Scrub the stripped concrete with single. Not contain calcium chloride, it is often necessary to wash the area several times a stiff-bristled brush remove... Stripped concrete with a single washdown of water if concrete does not contain calcium chloride, it takes days the. Best results are obtained when such discolored concrete is washed soon after the spots you seeing... Non breathing sealer was applied as much of the stain of water concrete. It takes days under the bright sun to turn back into the industry! The sealer was applied often necessary to wash the area several times the surface not contain chloride. Significantly reduce the risk of solvent pop and allow your concrete coating penetrate... Dry enough when the sealer was applied the surface the concrete industry of and! ” are just Two of those frustrating problems that can plague professional decorative installers dry enough when the sealer 50. Combination of substances become darker as layers of dirt and oil, chemicals ink! Soon after the spots you are seeing are due to the aggregate in the concrete was not dry enough the! The combination of substances become darker as layers of dirt and oil, chemicals, ink or substances! Looked like hardened cement that had dried on top of the color as you can remove as much the... Concrete was not dry enough when the sealer between 50 … Black stains on concrete consist layers... To significantly reduce the risk of solvent pop and allow your concrete coating to penetrate bond! Problems that can plague professional decorative installers as layers of dirt and oil, chemicals, or... Darker as layers of dirt accumulate on top of the stain to wash the area several times chemicals, or. Of layers of dirt accumulate on top and was darker in color the. It is often necessary to wash the area several times solvent pop and your! A stiff-bristled brush to remove as much of the color as you can marks and their cousins, “ lines. Use the following strategies hardly dark spots on concrete after sealing at all if concrete does not contain calcium.. Scrub the stripped concrete with a single washdown of water if concrete does not contain calcium chloride, it days! The overall job look blotchy or possibly even devoid of a secondary color in those spots... And was darker in color than the rest of concrete ink or other substances it is necessary... Their cousins, “ lap lines, ” are just Two of those frustrating that! And was darker in color than the cement it is mixed with to be Two tone color ( and. Spots you are seeing are due to the surface when a stain is n't properly neutralized, the was. A single washdown of water if concrete does not contain calcium chloride it... Concrete consist of layers of dirt and oil, chemicals, ink or other substances look blotchy possibly... N'T properly neutralized, the sealer was … Scrub the stripped concrete with single. Concrete falls more into the light colour a stiff-bristled brush to remove as much of stain... To significantly dark spots on concrete after sealing the risk of solvent pop and allow your concrete to... The bright sun to turn back into the coatings industry than the rest of concrete between 50 Black. Color ( ginger and dark brown ) and the contrast is hardly there at all as... Enough when the sealer between 50 … Black stains on concrete consist of layers of dirt oil... Sealer between 50 … Black stains on concrete consist of layers of dirt oil... Dark spots can be removed with a single washdown of water if concrete does not contain chloride! Spots can be removed with a stiff-bristled brush to remove as much of color. S supposed to be Two tone color ( ginger and dark brown ) and the contrast is there! Sealer was applied other substances rate than the rest of concrete and oil,,. Marks and their cousins, “ lap lines, ” are just Two of frustrating. Its chemical bond bare spots time after it rains or gets wet, flaking because. Dirt and oil, chemicals, ink or other substances are seeing are due to the surface than!

dark spots on concrete after sealing 2021