Pour Preparation

What is fiber reinforcement?

Fiber reinforcement is an economical and easy to use alternative to wire mesh reinforcement. It is extremely effective as it gets dispersed throughout the concrete load during transit to the jobsite. Unlike wire mesh that gets pushed to the bottom of the slab during the pour from workers walking on top of it, fiber will stay suspended within the slab. The fiber decreases the chances of plastic shrinkage cracking (a type of cracking common in concrete that isn't cured properly or has been subjected to harsh environmental conditions the same day it is poured) and essentially, helps to keep small, microscopic cracks from becoming large cracks. It is commonly used in conjunction with wire mesh as well. Fiber reinforcement is not usually an alternative for rebar.

Fiber comes in two different types. The first, commonly called "Regular fiber", is a fibrillated polypropylene (plastic) fiber and is easily seen in the concrete as well as during the finishing process. Usually, after poured, it will stick up out of the top of the slab. The other style, commonly referred to as "Stealth", lives up to its name as it is extremely difficult to see in the concrete. It is usually made up of fiberglass fibers (large enough so inhalation is not a concern), cellulose based or a monofilament polypropylene (plastic). This fiber is ideal for decorative or architectural concrete. It will not affect the color of concrete and does not affect the finish like "Regular fiber" does. I would not recommend anyone pour residential or commercial concrete without the use of fiber reinforcement

Why can't the concrete be sandier or wetter so it's easier to pour?

If too much sand or water is added to make the mix easier to use, the overall quality of the mix will be sacrificed. Wet, sandy concrete is easy to screed, but is weaker and more susceptible to cracking and surface blemishes such as efflorescence (unsightly white salt deposit). If too much water is used, the concrete will also be more porous as well as weaker. The more sand you put in the mix, the more water you need to make it workable, so it becomes almost a self feeding problem.

How do I prepare for my pour?

  • If hiring a contractor, make sure they are licensed and their license status is in good standing by visiting the Contractors State License Board and select "Check a license or HIS registration" on the left hand toolbar. Ask the contractor for recommendations of previous clients and make sure that you go see jobs they've recently completed. Check with our dispatcher or sales staff if they've heard of the contractor or know anything about them.
  • Find, clearly mark and notify all involved parties of jobsite hazards such as septic tanks, low hanging wires or tree limbs or other obstacles. Make sure all tree limbs are trimmed back and there is adequate access to and from the site. Please remember, as soon as our truck leaves the paved road, the property owner will be responsible for all damage that occurs to the truck or property (this includes tow bills if truck gets stuck).
  • You need to have an adequate area for clean-up. If not available, inform or dispatcher at the time of placing order for the necessity of a reclaim bucket on the truck. All fines for dumping in gutter or if runoff runs into the street will be paid by the owner. Please note that these can be extremely expensive depending upon your location.
  • Ensure your forms are sound and your grade is even. If your grade is off, even by ¼", it can result in a large difference in product required over the total square footage of the pour.
  • Make sure the contractor has accounted for proper drainage of water off the finished slab. There should be between 1/8" to ¼" inch of fall per foot to get proper drainage.
  • Ensure sure your grade is well compacted and damp, but no standing water present (such as puddles).

How do I determine how much concrete I will need?

You can use our Concrete Calculator or call us with your dimensions to get a rough estimate. Keep in mind that we cannot guarantee the proper volume or estimate required for your job, as we are not there to measure it ourselves. A small variance in measurement can make a large impact on overall requirement. For rough estimates, you can calculate 1 cubic yard of concrete will cover approximately 80 square feet when using a 2" x 4" form.

What are control joints and how many do I need?

One of the only guarantees with concrete is that it will crack. Control joints must normally be used to allow the concrete to crack at predetermined intervals. Although, if not placed close enough together or if not put deep enough into the slab, the concrete will seek its own location to crack. Please keep in mind that even though control joints are placed properly and at the correct intervals, this will not ensure that the concrete will not ever crack outside of the joints as there are many other factors that play into concrete cracking. This is the primary method of trying to minimize an undesirable outcome.

Determining where control joints go is almost an art form, but there is a method behind it. To determine the limits you're trying to work with, you should multiply the depth of the slab (in feet) by a minimum of 24 and a maximum width of 36. The maximum distance between joints should be 15 feet. The length shouldn't be any more than 1.5 times the width.

Example 1 - You have a sidewalk that is 40' long x 3' wide and 4" thick
  • Convert your depth into feet (divide 4" by 12" = .333)
  • Multiply this by 24 to 36 (.333 x 24 = 8' or .333 x 36 = 12')
  • The rule is no more than 1 ½ times your width (1.5 x 3' = 4.5'), so your spacing should be every 4.5' you should have a joint.
Example 2 - You have a patio that is 8' wide by 25' long and 4" thick
  • Convert your depth into feet (divide 4" by 12" = .333)
  • Multiply this by 24 to 36 (.333 x 24 = 8' or .333 x 36 = 12')
  • Your width will fit nicely between the 8' – 12' rule for the 4" thick concrete. This being the case, 1.5 times the width is 12 feet.
  • This is right at the maximum, so it may be advisable to joint it down the middle of the slab, but you should be ok at 12' as well.

If you have any other questions or concerns regarding concrete, our business, please do not hesitate to call our office at (209) 524-3177 or email us through our Contact Us page.