If your like me and math wasn’t your best subject in school, have no fear for Quilt Girl is here! She’s flown in special to show us how to calculate yardage for the dreaded 3B’s: borders, backing and binding. There will be three posts total breaking down each of the 3B’s.
Now what your going to need is a pencil, paper, calculator, your quilt top and something to measure it with (cutting mat or measuring tape), bottle of Advil or glass of wine.
Now just remember that you will be working in inches until the very last step when it will convert to yards.
Let’s start with borders:
First you need to decided one of two things: the size of the finished quilt or the size of your borders.
Step 1: Find out how big your quilt top is.
Measure the Width and Length of the quilt to find your size. Let’s say it comes to 40×50 inches.
Step 2: How big do you want your borders?
Let’s say you want a 5 inch border.
Now because there is two sides you will need to double the desired border size.
5 + 5 = 10
Take that number and add it to the width of the quilt.
40 + 10 = 50
We need to account for seam allowance so add 1 inch to that number.
50 + 1 = 51 inches
Here it is as a formula:
Border size x 2 = A
Width + A = B
B + 1 = C (New Width)
Step 3: Repeat for Length.
Now we’re going to repeat the exact equation for the Length.
Border size x 2 = A
Length + A = B
B + 1 = C (New Length)
Now you should have different numbers, for me its 51 as my width and 61 for the length.
Add those two numbers together: 51 + 61 = 112 inches
New Width + New Length = A
Step 5: Time to convert.
I have to total amount of fabric I need in inches but I need it in yards. So I’m going to take my 112 inches and divide it by 36 (36 inches = 1 yard).
112/36 = 3.1
A/36 = Total yardage
Since I ended up with 3.1 yards I’m going to bump my final cut up to 3.25 yards because it never hurts to have a little extra.
When I get ready to cut my borders I’m going to cut 5.25 wide inch strips. (Remember to add that 1/4 inch for seam allowance!) I will then sew the strips together until I have 2 strips that are 61 inches long and 2 strips that are 40 inches. 40 inches! But I thought it should be 51 inches! A very common mistake, but no worries! Take the original width, which in my case was 40 and sew it on. Then take the New Length, 61, and sew it on.
Take a sip or two and Good Luck!