(1) Check all concrete work proposals for rebar, wire, pumps, dumpsters, PSI levels (3000 to 4000 PSI is normal), gravel, etc. All of these items increase the cost of a concrete project. One company’s proposal can look much more attractive than another, but it may be lacking essential components. Don’t get stuck with these items as extras at the end of the project.
(2) Although many homeowners think concrete and cement are the same thing, they are not. In fact, cement is actually just a component of concrete. Concrete is made up of three basic components: portland cement, aggregate (rock, sand, or gravel), and water. Cement, most often in a powder form, acts as a binding agent when mixed with aggregates and water. The combination, or the mix of concrete, is poured and then hardens into the durable material that we are all familiar with.
(3) Concrete choices have increased to encompass many more options like decorative concrete, or colored cement, or painted concrete. There can be many different effects achieved today with new decorative applications. However, the more traditional gray concrete is still the most commonly installed option.
(4) Make sure the contractor explains the importance of the subgrade on your particular property application and how the subgrade should be compacted and have an even thickness.
(5) Reinforcement of the concrete can be achieved with either steel bars or wire mesh placed in a grid pattern. Reinforcement will not prevent cracks, but simply holds them together.
(6) Have the concrete contractor explain in detail the importance of ‘wearability’ with a ‘denser’ concrete at 3000 to 4000 psi. Many contractors may only use a more typical 2500 psi mix. A 4000-psi, .50 water-to-cement ratio is best for driveway construction, for example. Concrete is permeable and wicks moisture from beneath the slab. With the moisture come salts from the soil which can leave efflorescence on the surface. The .50 w/c mix provides a geometric reduction in this wicking action.
(7) For driveways, joints should be at least ¼ the concrete thickness, so a 1” deep joint should be used in a 4” thick driveway. Joints should also be spaced 2- 3 times in the feet thickness of the concrete. So, a 4” thick driveway should have joints in the 10-15’ range each way from center. If joints are spaced too far apart, cracks can often occur where the joints should have been.
(8) Make sure your contractor is fully insured, can provide many references and do not make your buying decision on price alone.
(9) Drainage for Driveways – the concrete should slope ¼” per running foot away from your home.
