A: Sealers with a higher solids content should not be used more than every other year. Lower solids content sealers can be resealed once a year.
Q: What is concrete and what are the basic ingredients?A:
Concrete is a mixture of portland cement, aggregate and water. The water and the cement combine to form a paste which binds the aggregates (gravel and sand) together to form a very hard, solid mass when set. Some concrete may also contain chemicals called admixtures. These admixtures are used to improve certain performance characteristics of the concrete. They may include bonding agents, water reducers, air entraining agents, accelerators or pigments.
A: Masonry mortar is composed of one or more cementitious materials, fine mason sand and sufficient water to produce a workable mixture. The cementitious material may be a portland cement/lime mixture or masonry cement. A typical mortar consists of 1 part cementitious material to 2 ¼ - 3 ½ parts sand by volume.
Q: When do you use mortar?A:
Mortar for unit masonry is intended to be used with brick, block and stone construction. The prime function of the mortar is to bond the individual masonry units into a consolidated mass. ASTM C270 is the Standard Specification for Mortar for Unit Masonry, which covers mortars for use in the construction of non-reinforced and reinforced unit masonry structures.
The three most commonly used types of mortars are designed as Type M, Type S, and Type N. Type M has a compressive strength of 2500 psi; Type S 1800 psi and Type N 750 psi . Type M is used only in special applications requiring high strength mortar. Type S is the most versatile and cost effective and can be used both above and below grade. Type N is limited to above grade construction.
A:
Portland cement is the most common cement used in concrete. The patent dates back to 1824 in England and is so named because the color of the cement resembled a stone found on the Isle of Portland. Portland cement is made by combining a mixture of ingredients, usually limestone, clay and shale, at very high temperatures. When mixed with water, portland cement forms a paste, which cures into a hardened mass. This chemical reaction is known as hydration.
Portland cement is a hydraulic cement. Any cement, which sets and hardens when mixed with water and is capable of doing so under water, is hydraulic cement.
Portland cement is usually gray in color but can be made in white or buff by adjusting the basic ingredients.
The two most commonly used types of portland cement are:
Type I - For general concrete work.
Type II - For moderate sulfate resistance.
The most commonly used form of Portland cement is designated Type I/II because it meets the requirements of both I and II.
A: One coat of the Sakrete Driveway Sealer is needed and recommended. Two coats may not allow proper drying.
Q: What can I use to repair areas that require a feather edge?A: The Sakrete Top'n Bond can be applied from ½” to a featheredge.
Q: What is the typical minimum thickness for concrete?A: Concrete is typically applied at a thickness of two inches or more. These applications would include drives, walkways, slabs and footers just to mention a few. With this type of application, both a fine and coarse aggregate are required. Sakrete High Strength Concrete Mix is ideal for these types of applications.
Q: Why is it important to include coarse aggregate in concrete?A: In thicknesses above 2 inches, the inclusion of a coarse aggregate (1/4 inch to 9/16 inch) is critical. All portland cement products shrink to a certain extent. Without the addition of coarse aggregate the shrinkage in these applications would likely be unacceptably high.
Q: What is hydraulic cement?A: Any cement, which sets and hardens when mixed with water and is capable of doing so under water, is hydraulic cement. This includes portland cement.
Q: What can I use to repair a small hole I have in my swimming pool?A: The Sakrete Leak Stopper can be used under water to repair a leak in a masonry swimming pool.
Q: How soon can I drive on my newly sealed asphalt driveway?A: You can drive on your newly sealed asphalt driveway after approximately 24 hours depending on temperature and humidity.
Q: What can I use to repair mortar joints?A: Deteriorated mortar should be chiseled out and replace with either Type N or S mortar. Sakrete Concrete & Mortar Repair can be used for small non structural repairs.
Q: Can Sakrete Glass Block Mortar Mix be used to lay brick?A: Yes. Sakrete Glass Block Mortar Mix is a Type S Mortar and can be used to lay brick.
Q: What are the advantages of using a filled driveway sealer?A: Sakrete Premium Filled Sealer provides added traction to the blacktop area while protecting the surface from gasoline and oil.
Q: What is ASTM?A:
ASTM stands for American Society for Testing and Materials. It is an international, non-profit organization founded in 1898. ASTM provides a forum for producers, users and consumers to write standards for materials, products, systems and services.
ASTM has developed standard specifications, which define the requirements that materials such as concrete and mortar are to meet. For example, ASTM C 387 specifies the strength requirement for concrete mixes.
A:
In applications where the physical limitations of the job dictate that the concrete be 1/2 inch to 2 inches in thickness, use Sand Mix. These applications would include an overlay on an existing concrete slab, a bedding mix for flagstone or brick patios, or walkways.
These applications preclude the use of coarse aggregate and instead contain portland cement and only a fine aggregate such as sand. In this case Sakrete Sand Mix is the material of choice.
A: A footing is a concrete base for a wall or other structure that provides stability and directly affects the performance and durability of that structure.
Q: What does it mean when “5000 psi” is printed on a bag of concrete?A: It means that, when mixed, placed and cured properly, the concrete can withstand 5,000 pounds of load per square inch.
Q: What is the largest area Sakrete Blacktop Patch should be used in?A: The Sakrete Blacktop Patch can be used to repair pot holes up to 3’ x 3’.
Q: How do I remove stains from my concrete surface?A: Sakrete Asphalt Cleaner removes or lightens grease and oil stains from Blacktop and Concrete surfaces.
Q: What is mortarless block construction?A: This type of construction allows the dry stacking of block without the use of mortar in the joints. Sakrete Surface Bonding Cement, with its interlocking fibers, can be used as a coating in place of mortar. Both sides of the wall must be coated. Check local regulations before using mortarless block construction.
Q: What is efflorescence and how can you correct it?A:
Portland cement, masonry cement and lime, as well as products containing these ingredients, such as concrete block, contain naturally occurring water-soluble salts. As moisture moves through the masonry, it dissolves and carries the salts to the surface of the masonry.
Once on the surface of the masonry, the water evaporates leaving a whitish deposit of salt on the surface. This natural formation of whitish surface staining is called “efflorescence.” When efflorescence is light, it can be removed with water and a brush. Severe cases will require the use of an acid.
A: Sakrete Sand Mix mixed with the Sakrete Bonder Fortifier would work well for these repair thicknesses.
Q: Does “cement” and “concrete” mean the same thing?A: No. Although often used interchangeably, cement is one of three basic ingredients in concrete. The other two are sand and stone.
Q: How soon can I seal over All Weather Blacktop?A: Sakrete All Weather Blacktop can be sealed after 60-90 days of warm weather.
Q: What is a good rule of thumb in determining the depth of a hole for setting a post?A: The depth for most heavy posts should be at least two feet. Another “rule of thumb” is that the hole’s depth should be 1/5 of the length of the posts and below the frost line. (Check local building codes to determine frost line depths.) To determine the diameter of the hole, measure the diameter or width of the post. The hole diameter should be at least 6 inches more than the post diameter or width.
Q: Is there a concrete mix that can be used for foundation or footings that does not require that it be mixed with water first?A: No. Due to the need for even compressive load distribution of a structure it would be recommended that the Sakrete Concrete Mix be mixed thoroughly prior to your application.
Q: Can I use Sakrete Blacktop Patch to extend my driveway?A: No. Sakrete All Weather Blacktop Patch can be used for pothole repairs or in contained areas. Extending a driveway is not a recommended application for this product.
Q: How do I repair cracks of less than ½” wide?A: Sakrete Concrete & Mortar Repair can repair cracks in concrete up to 1/4” wide. Sakrete Concrete Crack Filler can be used for cracks up to ½” wide.
Q: What is stucco?A: Stucco is the term used to refer to an exterior plaster usually composed of a standard plaster sand, portland cement, and hydrated lime or masonry cement and sand. The same mixtures are also conveniently available as Sakrete Type S Mortar Mixes. Application traditionally consists of one, two or three coats - scratch coat (first), brown coat (second) and finish coat (third or final) or brown and finish in a two-coat application
Q: How did the brand name "Sakrete" originate?A: In 1936, Art Avril, an engineer from Cincinnati OH, developed a process for drying and blending the ingredients necessary to make concrete and placing them in a “sack.” He named it Sakrete.
Q: Can I use mortar mix or sand mix to repair or build a fireplace or BBQ pit?A: No. Repairs or construction requiring high heat tolerances need a special refractory mortar.
Q: What is a slurry coat, and how is it used in concrete repair?A: It is a small amount of a cement mix that is mixed with water to the consistency of paint and brushed carefully into the pores and surface of the repair area just prior to placing the repair material. The slurry coat improves the bond of the repair to the original concrete surface.
Q: How can I set my post without mixing the concrete with water first?A: Sakrete Fast Setting Concrete Mix can be used for this application by digging the hole to desired size. Place approximately 2 inches of gravel at the bottom of the hole then fill the hole 1/3 with water, place the pole and pour or shovel the Fast Setting Concrete Mix into the hole adding more water and dry mix until hole is full.
Q: Why should I use bagged concrete and mortar mixes?A:
Bagged products are now the preferred method for most homeowners and many contractors. Most homeowner jobs require small quantities of material, making the use of bagged concrete the most practical choice. Many contractors prefer bagged material for variety of reasons.
Bagged products are ideal for those locations where ready mixed plants are too far away, or where physical access to the job site precludes the use of concrete mixers. The use of bagged mixes allows the contractor to place the concrete on his schedule, reducing his dependence on someone else. Factory blended bagged products offer a more consistent product than those mixed on the job site one shovel at a time.
A: Over-watered concrete may lead to lower strength, reduced durability, shrinkage cracking, and a variety of surface problems. It is critical that the proper amount of water be added to concrete and other cement mixes.
Q: Why is it important not to spend a long time troweling the surface of newly placed concrete?A: Excessive troweling after the placement and screeding of the concrete will bring excess fines and water to the surface, weakening the surface. Hairline cracks and dusting can result. Over-troweling the surface during finishing can produce the same problems.
Q: What is difference between anchoring and grouting?A: The term “anchoring” implies affixing an article onto or into another substrate. This is different from “grouting” which implies only the filling of a void or cavity between similar or dissimilar materials.
Q: What is the best product to use for a shower pan?A: Sakrete Sand Mix is recommended for this application due to higher strengths and greater thickness requirements. Although more workable, mortar may not have enough strength.
Q: Is it important to use clean water when mixing concrete and other cement mixes?A: Yes. Impurities, salt, organic material and other substances may have a negative impact on concrete. Generally, if you would not drink it, do not use it in concrete.
Q: Can Sakrete Sand Mix be feather edged?A: No. Sakrete Sand Mix can be used for applications of ½” to 2” in thickness. Sakrete Top n Bond is recommended for applications less than ½” thick.
Q: What material should I use for setting/grouting flagstone?A: Sakrete Sand Mix is a great product for installing and grouting flagstone due to the thickness requirements and the wearability of the Sand Mix.
Q: How many bags of concrete are required for one cubic yard?A:
Example:
60 x 60 lb. bags of Sakrete High Strength Concrete Mix will make a cubic yard
45 x 80 lb. bags of Sakrete High Strength Concrete Mix will make a cubic yard.
A: Retempering concrete mix or mortar mix is the addition of extra water to the mix after the initial mixing. It promotes shrinkage and reduces strengths.
Q: What does the term “curing” mean?A:
Curing is the action taken to maintain moisture and temperature conditions in freshly placed cement mixes allowing the cement to thoroughly hydrate. This can be done by misting the concrete, placing wet covers such as burlap on the concrete or by coating with Sakrete Cure n Seal.
Curing is necessary to for the concrete to achieve all of the desired properties. Additionally, the rapid loss of water from the surface of the concrete will cause the slab to cure at an uneven rate. This can happen during periods of high temperature or wind. If the top portion of the slab dries before the lower portion, the concrete will cure at different rates, causing the slab to develop cracks.
A: You can drive on your newly installed concrete after approximately 3 to 7 days depending on temperature.
Q: Is concrete waterproof?A: No. Portland based concrete mixes are not waterproof.
Q: How can I bond new concrete or repair material to my old concrete?A: Sakrete Bonder Fortifier will help to bond the new concrete or repair mortar to the old concrete.
Q: Can cement based products be placed in very hot or cold weather?A:
Cement based mixes can be successfully placed, finished and cured in both hot and cold weather, but it requires an understanding of the effect of weather on the material. For example, freshly mixed and newly hardened concrete can lose moisture in both hot and cold temperatures. In hot weather, cover the concrete with a wet, clean curing cloth and plastic.
Keep it continuously wet for a minimum of 3 days. In cold weather you should protect the newly placed concrete against early freezing for a minimum of 24 hours. Only a professional contractor should attempt to place concrete when the temperature is below 40 degrees.
A: The surface must be moisture free in order for most paints to stick. Typically paint manufacturers will allow a latex based paint after 7 days of curing. All oil-solvent based stains and epoxy materials will need to wait 28 days. Tape a piece of plastic about 8”x 8” to the concrete. If moisture droplets appear it is likely too wet to paint. Always check for paint manufacturers recommendations.
Q: How can I resurface my entire driveway or sidewalk?A: Sakrete Top’n Bond or Sakrete Flo-Coat. Smaller areas or those with a steep incline can be done with trowel applied Top ‘n Bond. Larger flat surface can be done with the more fluid squeegee applied Flo-Coat.
Q: When can I seal my new concrete?A: Sakrete Cure N Seal can be a curing agent and sealer applied 4-6 hours after placement of new concrete or after water or sheen disappears from concrete surface. All other sealing applications must wait 28 days.
Q: Can I add color to Sakrete concrete product?A: Sakrete Cement Colors can be added to almost all Sakrete products including mortars, concrete and repair products.
Q: Can Sakrete products be used over paint?A: Most portland cement based materials will not stick to painted surfaces.
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