We know there is a major technical advantage in using Fiber Reinforced Concrete versus wire mesh. The quantifiable evidence shows that the 3-dimensional fiber reinforcement is proactive whereas the single layer of wire mesh, at best, is reactive.
The economic benefits significantly multiply the value of using Fiber Reinforced Concrete.
Here is how to compare the in-place cost of the wire mesh with the in-place cost of both microsynthetic and macrosynthetic fibers. *Note: The following is a generalized economic breakdown of wire-mesh vs. fiber. Actual savings may be greater than, or less than the breakdown below. The project location and job specs may greatly differ in terms of material cost, labor cost, and mix design cost. The main takeaway from this article is that fiber is the more cost-effective choice when wire-mesh, #3, or #4 rebar is needed on a jobsite.
Wire Mesh Cost
Material Cost. This is the actual cost of the wire mesh required by code, which includes the overlap. Here the square footage of the project is multiplied by a factor, like 110% to come up with the actual wire mesh required for the project. This factor would include the overlap and waste of the wire mesh.
Cost to handle the wire mesh on the project (off-load from truck, store, move to point of use). Remember to include the cost of the forklift and operator.
Cost to place the wire mesh (this cost is in direct labor expenses plus the time lost to place the wire mesh). Remember to include the cost of the forklift and the operator. Typically a four man crew is required.
Cost of permanent supports on which to place the wire mesh.
Cost for concrete pump to place the concrete (ready mix trucks are not permitted to drive on the wire mesh)
Wire Mesh a Costly Choice
6×6 W1.4 x W1.4Wire Mesh Material Cost$0.28/sfCost of Handling$0.03/sfCost to Place Wire Mesh$0.10/sfCost of Permanent Supports$0.03/sfCost for Concrete Pump @ $750/day$0.075/sfTotal Cost In-Place for Wire Mesh$0.51/sf*
Factors used in developing the in-place cost for the wire mesh:
The above costs are estimates and based on a 5” thick concrete slab and a per day placement of 10,000 sq ft. Actual costs will vary based on market conditions and location.
Labor force to place the wire mesh would include 4 laborers. If union iron workers are required per the project contract double the cost to place the wire mesh. The cost of one operator and forklift to move the wire mesh from storage to point-of-use was not included.
The cost of the wire mesh is based on 6×6 W1.4xW1.4, as noted.
The cost of 6×6 W2.9 x W2.9 in place would be $0.51/sf.
When costing out a slab-on-ground also include the cost of a concrete pump with the wire mesh in-place cost. When wire mesh is used the ready mix trucks are not permitted on the base. When fibers are used the ready mix trucks can pull up on the base and discharge the concrete at the point of use. In this exercise the up-charge used for the concrete pump and operator is $750/day.
Remember that the placement time for the wire mesh is increased measurably when permanent supports are required by the engineers.
This cost does not include lost time required to place the wire mesh nor does it include the cost associated with the required overlap of the wire mesh specified by code.
Further Considerations
If we are conducting a true accounting of cost when wire mesh is used, we must factor in the time used to place the wire mesh twice. Not only is it a cost, but it also may be considered lost revenue from use of work force and equipment on another task or project. View the number of days to place the wire mesh as lost days in the construction time schedule. One of the biggest benefits of using fiber is the ability to schedule more jobs, and/or to move labor to other projects. Your crew should be paid to place and finish concrete, not to place wire-mesh or rebar on jobsites. Cost of labor is greatly decreased, as well as paying benefits, insurance, and other related costs. ** The cost of #3, or #4 rebar is an increased cost not only in material, but labor, as it is a more time intensive, and the cost to place and secure rebar for a concrete pour is greater as well. Generally, microfiber will be used to replace wire mesh, while macrofiber will be used to replace rebar.
Fiber Cost
Cost of the fibers in the truck is the total cost. There are no additional/extra costs.
For residential slabs-on-ground the Total Cost In-Place for Microsynthetic Fiber using the same basic parameters would be $0.13/sf based on a fiber dosage of either 1 or 1.5 pounds per cubic yard.
Fiber is the Smart Choice
6×6 W1.4 x W1.4Microsynthetic Fiber Cost$0.13/sfCost of Handling$0Cost to Place Wire Mesh$0Cost of Permanent Supports$0Cost for Concrete Pump @ $750/day$0Total Cost In-Place for Microsynthetic Fiber$0.13/sf*
Fiber is the Smart Choice
6×6 W1.4 x W1.4Microsynthetic Fiber Cost$0.38/sfCost of Handling$0Cost to Place Wire Mesh$0Cost of Permanent Supports$0Cost for Concrete Pump @ $750/day$0Total Cost In-Place for Microsynthetic Fiber$0.38/sf*
Factors used in developing the in-place cost for the wire mesh:
The above costs are estimates and based on a 5” thick concrete slab and a per day placement of 10,000 sq ft. Actual costs will vary based on market conditions and location.
For industrial, warehouse and roadway slabs-on-ground the Total Cost In-Place for Macrosynthetic Fiber for a similar application would be $0.38/sf based on a fiber dosage of 4.0 lbs/cy. Fiber dosing for industrial/commercial applications may vary based on specifications. Please contact us to discuss such applications for your project so we can maximize your savings.
Note: Prepared by R.C. Zellers, PE/PLS, ABC Polymer, Director, Engineering Services