Concrete calculator is a simple but helpful concrete estimator. Simply enter the
feet and inches of the length, width, and depth of the slab or footing. The
Concrete calculator will calculate the square feet, cubic feet, and cubic yards of
the project. Enter the amount of waste and the cost per yard of concrete and the
total cubic yards of concrete and the total cost will be shown in the text box. You
will also be able to add or subtract the totals of the concrete amounts and the
material costs as the you calculate the job
With Concrete calculator after you put in all the dimensions, concrete cost and %
of waste (optional), just press the Add Input button. This will total everything and
give you the total cubic yards in the Total Cubic Yard box. If you have other
footings or slabs to add, just press the Clear Boxes button. This will clear all of the
dimension buttons. Enter the new dimensions and press the Add Input button. This
will add the new amount to the existing total. If you make a mistake press the Clear
Boxes button and enter the dimensions of the section you want to subtract. After
entering the dimensions press the Subtract Input button and it will adjust the
quantity and cost. When you want to start another job press the New Job button on
Concrete calculator and all the boxes will clear.
Concrete is one of the main building products used in the construction of a house. Depending on where the concrete is used in the construction
process, it can become a very critical factor in the overall structural strength of the house. Just because the concrete comes premixed in the
concrete truck does not mean that the concrete is always good.
A hole 3 feet by 3 feet and 3 feet deep would require one yard of concrete to fill the hole. Another value that is used when pouring sidewalks and
driveways is that a yard of concrete will cover eighty one square feet of area (driveway or sidewalk) when the concrete is four inches thick.
The next issue discussed might be the strength of the concrete. Years ago, the only strength concrete used in house foundations was 2000 psi
(pounds per square inch) concrete. It's not unusual today to see builders pouring 3000 psi and 4000 psi concrete, depending on the size and
complexity of the project. Some of the larger homes are designed by an architect and might require a structural engineer. The structural engineer
might require mix designs from the concrete company for his approval.
The sales person might ask next what kind of "slump" is required. This is sometimes where the concrete subcontractor and the builder might try to
reach a compromise. The lower the slump the greater the strength but the harder the concrete is to work. The higher the slump the lesser strength
but the easier the concrete is to work. When a structural engineer is involved, he might specify that the concrete is to be 3000 psi with a three to
five inch slump. If this is specified, it is very important to stay within these limits do not allow anyone to add water to the mix on site without
permission from the individual doing the testing. If the concrete is being pumped, there are additives that can be added to the mix in order to allow a
higher slump but not jeopardize the strength of the concrete. These additives can also be used in dry and windy climates to allow a wetter mix and
hopefully prevent surface cracking due to the fast dehydration of the concrete. If the concrete is tested, the slump might be checked every fifty
yards and the cylinders might be taken at the same interval. Concrete cylinders are taken and tested to verify the compressive strength of the
cured concrete. The cylinders are compressed and broke at specified intervals. A cylinder broke after 28 days should break at the designed
strength or greater.
Also, usually the temperature of the concrete will be checked at this time. The temperature of the concrete might become more of a factor in the
summer rather than the winter. A rule of thumb might be that if the concrete temperature is above 95 degrees it is not acceptable to pour in the
foundation or footings. Sometimes a good starting point to monitor the temperature of the concrete in a truck is to check the ticket and see when
the truck was loaded at the plant. In warmer climates, the longer the concrete is in the truck the hotter the mix. In cooler climates the temperature
might not be out of range but the time in the truck might become a factor. Usually a rule of thumb might be that, if it has been forty five minutes to an
hour since the truck was loaded, the load may have started setting up and might not be acceptable to use.
As you can see there are a few more things to consider in foundation concrete other than just pouring the concrete out of the truck. As in most any
other construction process, a little pre-planning and basic knowledge might prevent a major mistake that could cost a lost of time and money.
Category Construction Glossary