(Floors - TotalConstructionHelp)

Floors

Before you can put down a carpet, or install tile or any material on a Floor, you will need a Floor, such as, concrete or wood.

If you are building a small cabin in the woods, or a house, or an office, you will need a Floor. The following is an example of how to calculate how much concrete you will need for a Floor, next you will be shown how to calculate tile, or carpeting, for the Floor.

For Example 1, assume that you have a small cabin that you want to build. The cabin is to be 12 feet wide by 17 feet long, with a typical Concrete Floor on the ground that is 4 inches thick. At times it may be thicker.

Our examples will show how to determine the concrete needed for a 4 inch and a 6 inch concrete slab.

This is a 12 foot by 17 foot Floor Slab that is 4 inches thick, with a 10 inch by 16 inch wide Monolithic Footing.

See Example 1, for method of calculations

Example 1:

Step to calculate the concrete needed

Multiply the 12 feet by 17 feet
1. the Result is 204 square feet
If the Floor is to be 4 inches thick, we will convert the 4 inches into feet.
1. to convert 4 inches into feet, we will divide 4 inches by 12 inches (which is 1 foot).
2. therefore, 4 divided by 12 = .33333 feet
We now have the floor area which is 204 square feet and the depth of the slab which is .33333 feet
1. now we will multiply 204 square feet by .33333 to get the volume of concrete.
2. therefore, 204 multiplied by .33333 = 67.99932 cubic feet
Concrete is delivered from a Batch Plant in a Concrete Delivery Truck, and concrete is sold by the cubic yard.
1. a cubic yard is a box that is 3 feet wide by 3 feet high by 3 feet deep.
2. therefore, 3 feet by 3 feet by 3 feet = 27 cubic feet, which is 1 cubic yard.
Since our project is 67.99932 cubic feet, all we need to do is divide 67.99932 by 27 to obtain how many cubic yards of concrete we will need.
1. the cubic yards we need are, 67.99932 divided by 27 = 2.5184933 cubic yards of concrete.
2. usually, you can add a little extra concrete since the floor will have some irregularities. On a small project, such as this one, you can add about 10%,, which would mean that you will need about 2.77 cubic yards of concrete.
3. before ordering concrete, verify if the delivery can be in less than a full cubic yard. Most times the company will deliver in yard quantities, which means that if you need 2.77 yards of concrete, they will deliver 3 yards. You will then need to decide what to do with the extra .23 yards of concrete. You may be able to use this extra concrete to make a stoop, or some steps, otherwise, it may just be thrown away.

Suppose you also have a perimeter footing that is 10 inches deep by 16 inches wide that is part of the slab. This is called a monolithic footing.

To calculate the footing, take the perimeter length of the slab, which is 12 feet plus 12 feet plus 17 feet plus 17 feet = 58 lineal feet. The footing depth is 10 inches of depth minus the slab thickness of 4 inches = 6 inches.

Therefore, the concrete for the footing is;
6 inches divided by 12 inches = .5 feet
Multiply .5 times 58 = 29 cubic feet that is divided by 27 cubic feet = 1.074 cubic yards of concrete for the footing.

For the slab and footing, the total amount of concrete is 2.5184933 cubic yards for slab plus 1.074 cubic yards of concrete for the footing, for a total of 3.5924933 cubic yards of concrete, plus 10% extra = 3.952 total cubic yards of concrete.

For Example 2, assume that you have a cabin that you want to build. The cabin is to be 15 feet 8 inches wide by 22 feet 6 inches long, with a Concrete Floor on the ground that is 6 inches thick.

Example 2:

Step to calculate the concrete needed

Multiply the 15 feet 8 inches by 22 feet 6 inches
1. first convert the 15 feet 8 inches into feet, by dividing the 8 inches by 12 inches = .67 feet, and adding 15 feet and .67 feet = 15.67 feet
2. also convert the 22 feet 6 inches into feet, by dividing the 6 inches by 12 inches = .6 feet, and adding 22 feet and .5 feet = 22.5 feet
3. now multiply 15.67 x 22.5 = 352.575 square feet
If the Floor is to be 6 inches thick, we will convert the 6 inches into feet.
1. to convert 6 inches into feet, we will divide 6 inches by 12 inches (which is 1 foot).
2. therefore, 6 divided by 12 = .5 feet
We now have the floor area which is 352.575 square feet and the depth of the slab which is .5 feet
1. now we will multiply 352.575 square feet by .5 to get the volume of concrete.
2. therefore, 352.575 multiplied by .5 = 176.2875 cubic feet
Concrete is delivered from a Batch Plant in a Concrete Delivery Truck, and concrete is sold by the cubic yard.
1. a cubic yard is a box that is 3 feet wide by 3 feet high by 3 feet deep.
2. therefore, 3 feet by 3 feet by 3 feet = 27 cubic feet, which is 1 cubic yard.
Since our project is 176.2875 cubic feet, all we need to do is divide 176.2875 by 27 to obtain how many cubic yards of concrete we will need.
1. the cubic yards we need are, 176.2875 divided by 27 = 6.5291667 cubic yards of concrete.
2. usually, you can add a little extra concrete since the floor will have some irregularities. On a small project, such as this one, you can add about 10%,, which would mean that you will need about 7.182 cubic yards of concrete.
3. before ordering concrete, verify if the delivery can be in less than a full cubic yard. Most times the company will deliver in yard quantities, which means that if you need 7.182 yards of concrete, they will deliver 8 yards. You will then need to decide what to do with the extra concrete. You may be able to use this extra concrete to make a stoop, or some steps, otherwise, it may just be thrown away. Or you may be sure that the slab thickness is as close as possible to the 6 inch thickness.

If a footing is required, then apply the same procedure as above.

You have other options beside purchasing concrete that is ready to pour.

You can buy premix in a bag from you local construction material outlet. The premix comes in bags that already contain the sand, cement and gravel, in proper proportions, and if the correct amount of water is added, it will produce the desired concrete strength. With the premix, all you need to do is mix water into the mix, as specified on the bag. A bag usually contains 40, 60 or 80 pound per bag. A 40 pound bag yeilds about .30 cubic feet of concrete. A 60 pound bag yeilds about .45 cubic feet of concrete. A 80 pound bag yeilds about .60 cubic feet of concrete.

Another option would be to buy a load sand, bags of cement and a load of gravel and mix them together with water. To do this you will need to know the quantity of sand, cement, gravel and water to mix. It requires that proper quantities of each be mixed to get the proper strength in the concrete. Try this simple time-tested mixture formula as a guide; 1:2:3 parts by dry volume. That is: one part Portland cement, two parts sand and three parts coarse aggregate.

Use a shovel to scoop these elements into a large wheelbarrow or a concrete mixing trough. It's wise to start with a moderate amount of dry mix as it gets exponentially harder to mix as water is added.

Use the minimum amount of water possible while still keeping the mixture workable. The less water used, the stronger the dried, finished product will be.

Find the approximate proper wet consistency by again thinking of a well-mixed cake mix for thickness. Be sure that it is evenly and completely mixed.

Try to use the same amount of water for additional batches to be mixed, and work fast to keep dry lines from forming. This is where the concrete is already drying and the transition to the new, wetter mix will be clearly visible and create a weak point.

Remember that water is the key ingredient. Too much water results in weak concrete. Too little water results in a concrete that is unworkable.

After concrete is placed, the concrete increases in strength very quickly for a period of 3-7 days.

Concrete which is moisture cured for 7 days is about 50% stronger than uncured concrete.

Water curing can be done after the slab pour by building dams with soil around the house and flooding the slab.

The enclosed area is continually flooded with water. Ideally, the slab could be water cured for 7 days.

Some builders on a tight schedule water cure for 3 days as this achieves approximately 80% of the benefit of water curing for 7 days.

Consider planning your project to pour at the end of the week, build berms, then flood over the weekend.
You get the benefit of water curing without losing too much time in the schedule.

Some Floor coverings

Carpet
Bamboo Flooring
Carpet Tiles
Cork Flooring
Hardwood Flooring
Laminate Flooring
Rubber Flooring
Area Rugs
Tile & Stone
Vinyl Flooring
Other

Not all Floor covering are computed in the same way.

Carpet is usually calculated in square yards, while most other Flooring is calculated in square feet.

Assume a room of 14 feet 3 inches by 15 feet 9 inches

For square feet, convert 3 inches to feet and 9 inches to feet
1. divide 3 inches by 12 inches = .25 feet
2. add 14 plus .25 = 14.25 feet
3. divide 9 inches by 12 inches = .75 feet
4. add 15 plus .75 = 15.75 feet
5. Multiply 14.25 by 15.75 = 224.4375 square feet
For square yards (carpet) convert square feet to square yards
1. one square yard = 3 feet by 3 feet = 9 square feet
2. divide 224.4375 square feet by 9 feet = 24.9375 square yards

Add 5-10% extra material for cutting waste. When purchasing Floor covering material, it is usually sold in boxes that cover a fixed area. Some boxes will cover 20 square feet per box, while others cover 18.62 or some other area.
To determine how many boxes you will need, simply divide the area by the area that can be covered per box. In this example we will consider that a box will cover 20 square feet.
As an example, if the area is 224.4375 plus 10% waste = 246.88 square feet, then divide 246.88 by 20 square feet per box coverge = 12.344 boxes needed. You will need to purchase 13 boxes, since you need more than 12.
Some Floor covering require underlayment. Verify with the Supplier.