Concrete

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: When would you use Sand Mix?

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.

Q: What is a footing?

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 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: 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 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 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: 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.

Q: How soon can I drive on my new concrete?

A: You can drive on your newly installed concrete after approximately 3 to 7 days depending on temperature.