Guest Author - Iris ten Holder
Although braided rugs were traditionally made from rags or remnants, we can also use new fabric to make the strips. In that case it is useful to know how to calculate the number of yards needed for a rug.
The fact that there are several fabric widths makes it seem somewhat complicated.
I sat down, made some calculations and came to the following formula which - as is the case with all formulas - makes only sense to us if we know what the letters stand for.
If XF=A*Q then F=A*Q/X
Using the letters instead of actual numbers makes this formula flexible, so we just plug in the numbers to get the result.
A = sq.ft. of rug
Q= strip length needed
X= Fabric width
F= strip length divided by fabric width.
We can do these calculations in three steps,
Let's start.
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Step One -
A - Calculate the surface area of your rug
Thanks to mathematicians, we know that the formula to determine the surface area of a circle is Pi x r2. In layman's language this means:
Half the diameter (D) squared (multiplied by itself), multiplied by 3.14 (Pi)
A =1/2D * 1/2D * 3.14
Therefore: for a round 1 x 1 ft rug A = 0.79
For an oval rug we use half the width and half the length
A=1/2W * 1/2L * 3.14
Therefore for an oval 1 x 1.5 ft rug A = 1.18
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Step Two:
Q - Quantity of strips needed.
This is the heart of the calculation.
Assuming that the strips are 1” wide, that there are three strands in the braid and that the braiding factor is 2, the formula to calculate the length needed is:
12 *12 *3 *2/36
This can be simplified to 12*12/6
This tells us that each square foot requires 24 yards of fabric strips.
If any of these factors change, such as wider strips, or more strands in the braid, the requirement changes and influences the calculation in Step Three
For example, for a four-strand braided rug, the calculation would be 12 *12 *4 *2/36. In addition, the braiding may take up more of the fabric, so the second-last factor may need to be changed as well.
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Step Three:
F - Fabric yield
1. Determine the width of the strips (our sample is 1")
2. Measure the width of the fabric
3. Calculate the number of yards needed by dividing Q by the width of the fabric.
A Q 36" 54" 72"
Sq.ft. yards yards yards yards
1 24 0.67 0.44 0.33
Note: The strips are best cut lengthwise with the grain of the fabric. Therefore round off the yard requirement up to the next full yard.
Please realize that these are theoretical calculations and that there are many variables that may influence the outcome when real fabric is used. Therefore I urge you to make a sample, using similar fabric. From the calculations it is clear that one-yard will be adequate to make a one-foot sample.
