2,500 PSI Concrete vs. Higher PSI Concrete

The use of the slab will determine the strength of your concrete. However, 2,500 psi is the most often specified for low performing slabs. For example, a Home Depot that has a lot of foot traffic and fork lift traffic and abuse from dropping lumber and other items usually specifies a concrete strength of 4,000-6,000 psi along with other high performance specifications. In most areas the cost of concrete from 2,500 psi to say 3,500 psi is neglible maybe $1-$4 per cu yard. There is a caveat though with specifying the higher psi concrete; the code states that any concrete over 2,500 psi shall have cylinder tests taken and the test results submitted to the building official. We recommend leaving the concrete strength at 2,500 psi on the plans and calculations and going ahead and pouring a 3,000 or 3,500, this avoids the additional cost of the testing. However, if the use of your building needs a higher strength we will specify the appropriate strength. Commom places for higher strength concrete is diesel mechanic shops, rack storages and any high fork lift traffic.

Cost vs. Installed Cost

Many times I find people making valuable purchasing decisions based on cost alone with total disregard to installed cost. For example a 40' x 60' x 16' tall building with a wind post may cost around $14,000.00 but a building with a wind bent for lateral bracing may cost $14,750.00. They figure the prices are close therefore go with the cheaper bid. However the additional concrete on the wind post may cost as much as 5-6 times the savings. ALWAYS ASK YOUR METAL BUILDING COMPANY IF THEY ARE USING WIND POSTS IN YOUR METAL BUILDING.

Welded Wire Reinforcement vs. Rebar

We are often asked what is better Welded Wire Reinforcement (WWR) or Rebar for slab reinforcement. Our answer is two fold. WWR is a great reinforcing material when it is placed properly in the slab. WWR comes in two forms, rolled wire reinforcement and sheet wire reinforcement. The rolled wire reinforcement is very difficult to place in the slab. It is walked on and pulled up from the bottom through the concrete to the center of the slab or there abouts. the truth of the matter is it usually stays on the bottom. It is hard labor to pull the wire up and to keep someone doing it while pouring concrete. On the filp side the sheet wire reinforcement comes in sheets of 8' x 20' and are stiff enough to be placed on concrete dobies or plastic chairs. This keeps the reinforcement at the right depth while placing the concrete. We typically recommend sheet wire reinforcement in larger jobs. Sheeted wire reinforcement can be used on any size job.

Rebar is a great slab reinforcement. It is just labor intensive in placing, and tying the laps and joints. Rebar is then placed on concrete dobies or plastic chairs and is usually spaced at 18"-24" on center each way, so it is easy to step around and easy to place concrete. Rebar is still used in the perimeter footer and the support footings beneath each column. We recommend the rebar on jobs under 15,000 s.f.

Foundation Design

We are often asked why should we use Salsa Steel Corp. Our answer is becuase we will save you money every time. Most engineers over-design metal building foundations 25-200%. Guess who pays for that extra concrete? (YOU DO!) We don't stop at the first answer that works. We optimize every foundation for every building. We never reuse any design. Each building has a unique design. Plus we guarantee that you will have your foundation design with 10 days or less!