Although the bulk of the hydration process takes place in the hours and days immediately after the pour, concrete needs 28 days to fully dry. While the slab will harden and lighten in color before 28 days, don't be fooled into thinking it's done hydrating.
Can I use a gray concrete and still get a white countertop? No. A true white color can only be achieved using a white cement mix. Add white concrete pigment to a gray concrete mix to create a sleek “ash” look that's popular in modern homes.
Fresh concrete is always much darker than when it is fully cured and dry. Even uncolored concrete. Wait at least 7 to 10 days until the new concrete has hardened and dried. If the concrete is on a wet subgrade or there's underground water, it may stay dark for as long as it's wet.
The dark gray discoloration is caused by varying degrees of hydration of the cement in the concrete, caused by the varying moisture contents in the localized areas of the total concrete.
Concrete will continue to lighten until it is fully cured. Allow the concrete to cure at least 30 days before inspecting it for color match or appearance.
Although the bulk of the hydration process takes place in the hours and days immediately after the pour, concrete needs 28 days to fully dry. While the slab will harden and lighten in color before 28 days, don't be fooled into thinking it's done hydrating.
Usually this white or off-white discoloration to concrete and masonry forms when soluble salts and other water dispersible materials come to the surface through capillary voids as a result of temperature changes, moist migration, condensation, rain, dew, and/or too much water in the mix.
Cleansing — For mild discoloration, repeatedly flushing the hardened concrete surface with hot water, then scrubbing with a stiff brush, can reduce or remove discolored blotches. Acid treatment — If the discoloration is more severe, a mild acid solution of 1-3% muriatic acid to water can help remove the discoloration.
Read on to know more! It contains a high amount of iron oxide and manganese oxide, which end up giving the cement that classic grey colour. It contains iron and manganese, but not in oxide forms, which end up giving the cement its white colour.
Why is my concrete turning white? Efflorescence is a white salty residue caused when too much moisture is moving through the concrete. As the concrete dries and its moisture rises upwards through the slab, it brings salts within the concrete to the surface as well.
Whitening is a phenomenon that occurs once the concrete hardens and starts to absorb water. So if you want to prevent your concrete from turning white you need to prevent water absorption. The best way to do this is a good quality sealer.
Young concrete / green concrete is in the curing phase during these four weeks. Hardened concrete is called the building material after 28 days, on / with it the construction can proceed. After several months, the moisture has largely evaporated. After years the final strength is reached.
Use a garden hose or pressure washer, and saturate the concrete surface with lots of water. Then let Mother Nature take effect. Multiple water-soaking cycles may be needed, and there is no guarantee that the color will lighten to the desired shade, if at all.
Answer: The short answer is, yes. Acid stain will work on any concrete, colored or gray. The big difference will be the final color.
Gray cement can be light, dark, brownish, greenish or some other shade, hue and variation of gray.
In the market, grey cement is used very commonly by everyone, whereas white cement is generally used for decorative and beauty purposes. Both white and grey cement is usually ordinary portland cement ( OPC) but white cement is much finer than grey cement but almost equal in strength.
Concrete is an inexpensive, durable building material, but all that gray can be a bit boring. You can paint or stain just about any concrete surface—a walkway, concrete stairs, concrete brick walls, or even a basement or garage floor.
Production of white concrete with a compressive strength between 25 and 50 Mpa is possible by using white cement. It was also found out in study that white concrete had higher compressive strength than normal gray concrete.
The product's major asset, aside form its striking architectural beauty, is its ability to remain white throughout its life. White concrete, obviously, is not a surface treatment that can deteriorate with age.
Steps to recolor faded stamped concrete:
Apply additional coats of stain without waiting for the first coat to dry. Allow the final coat of antiquing stain to dry for at least 8 hours. Once the stain has fully dried, apply a solvent-based acrylic concrete sealer to protect the color from fading in the future.
For subtle color correction, a pigmented sealer may be enough. Sealing or resealing one or both slabs with a pigmented sealer can provide a quick and easy fix while providing protection that is already necessary for decorative concrete.
In fact, many concrete staining products come with a long time guarantee. It's a different situation if concrete staining applies to the concrete. It's recommended to stain the concrete once in four years to enhance the color that fades away, especially if its exterior surface that is exposed to sunlight.
Fade Color
If you have a colored concrete driveway, the UV rays of the sun can fade it. If the sun is not hitting all of your driveway, then you will see patches of color that are more faded than others.
Concrete discoloration is not a rare event
Variability in concrete mixtures. The use of too much or not enough water. The use of calcium chloride. Improper concrete laying techniques.
Production of white concrete with a compressive strength between 25 and 50 Mpa is possible by using white cement. It was also found out in study that white concrete had higher compressive strength than normal gray concrete.