Home » Guest Contributor Kim G. » Add a Color Block Stripe to a T-shirt (…to add length)

Add a Color Block Stripe to a T-shirt (…to add length)

So happy to have Kim back today from The Sew Spot! I’m loving her post today because we have the same problem around here….kids that grow up way too fast!  Such a great way to make kids clothes last a little longer! :)

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Lately, it seems as though, if my son is not eating, he is asking what there is to eat.  A growing boy needs his food and that means he’ll also need some new clothes that will fit.  Instead of buying him new clothes, just yet, I decided to add a color block stripe to a shirt he already has to improve the fit.  The goal was to increase the length of a shirt that was too short to wear.


Adding the color block stripe increased the shirt length by almost 2″.  That doesn’t seem like much, when I thought about it, but the shirt fits him so much better now.  (You could make the shirt even longer by increasing the length of the stripe.)


The color block stripe goes all of the way around the shirt.


If you want to add a color block stripe to a shirt, here are the supplies you’ll need.

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  • Shirt to alter (the grey one)
  • Old t-shirt/fabric of similar material to the shirt you are altering (the teal one)
  • Scrap fabric for pocket (optional)
  • Hem tape
  • Scissors
  • Seam ripper
  • Chalk/invisible pen
  • Sewing machine
  • Thread
  • Iron



Start by deciding where you want the color block stripe to begin.  I chose right under the white stripe, cut 1/2″ below it (for a seam allowance), and then seam ripped along the sleeves.  Now there are two pieces.  On the top piece, measure along the cut that was just made. (Basically, cut and measure from here to here in the photo.)


Use that measurement as the length of the rectangles you will cut from your chosen fabric.  The size of the rectangles I used where 16 1/2″ x 4″. (Again, you can make the color block stripe longer by making the rectangle longer than 4″.)


Take the bottom portion of the shirt and put it on top of the fabric rectangles.  It may help to fold all pieces in half to find the center, mark with a pin and line them up.  Use the shirt as a guide, and cut the curved shape out of the rectangles.


The rectangles should now look like this. (One is for the front and the other is for the back.)


Pin the fabric to the shirt right sides together and sew.  Repeat with the second piece of fabric on the back side.  Don’t worry if there is extra fabric on each side, it will be trimmed later.


I used a narrow zigzag stitch and cheated a little by sewing right along the white stripe.  If your shirt doesn’t have stripes to use as a guide, you could use 1/2″ seam allowance.


Now that you’ve finished using the bottom portion of the shirt as a template for the color block stripe, cut just under the arm curves.


Place the bottom part of the shirt on top of the fabric and draw a slight curve from the seam of the arms to the corners of the shirt.  I used chalk, though an invisible marker would also work.


Sew along the curve and cut any excess fabric.  A serger would be nice, but I just used the narrow zigzag stitch.



Now, put the top piece of the shirt inside of the bottom portion of the shirt with right sides together.


Pin all of the way around and sew with 1/2″ seam allowance.


Turn inside out and press the seams flat.


All done…Unless, you want to add a pocket.


I found this piece of scrap fabric that is 3 1/4″ x 3 1/4″.  With not much fabric to work with, I just folded the edges in 3/4″ and adhered each side down with a small piece of iron-on hem tape.


Pin the pocket, and sew around the two sides and bottom of it with a straight stitch.


I think the pocket brings everything together.


I’m glad his ‘new’ shirt is just the right length.


Hopefully, we’ll squeeze one more season out of this shirt without having to squeeze into a shirt that is too short.


If you’re interested to see a similar shirt, remade in a slightly different way, visit The Sew Spot.



You can find more from Kim over on her blog The Sew Spot, Pinterest and Facebook.


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Looking for more?

Turn Old Sweaters into Cozy Leggings

Turn a Men’s Tie into a Little Boy’s Tie

Turn Too-Small Tights into Leggings

Add a color block stripe to boys t shirt
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  1. Mandy May says:

    This is such a smart idea! My husband has a bunch of shirts from high school that he likes too much to throw out but they are too short to wear. I’ll have to try this on one of them.

  2. CJ says:

    This idea works really well for boys and girls shirts. I’ve been doing this for my son’s shirts for a few years. Keep in mind the color block really can be placed anywhere on the shirt. My son happens to be very, very sensitive about seams, so I add the block lower down, so that the unfinished edges of the shirt do not rub against his chest.

    1. Kim says:

      You are good CJ! I wish I would have thought about doing this for my son’s shirts a little sooner. Thanks for the thoughtful advice on the shirt variations and seam placement! I was unsure how a shirt would turn out if the additional fabric was placed lower, so I tried that too. You’re right, it does work! I was actually pleased by the way it looked when I added the fabric closer to the bottom of another shirt.

  3. Kristie says:

    Kids do seem to grow up more than they grow out! Thanks for sharing!

    1. Kim says:

      Good point Kristie! That is certainly the case with the kids in my house!

  4. Tammy says:

    Genius! It seems the shirts we buy for our tall and slim grandson are too short almost overnight and here’s the remedy. Great tutorial. Thank you!!

    1. Kim says:

      Tammy, that is very true! They grow up and out of their clothes too quick! I’m glad you liked the tutorial, thanks!

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Hi, I'm Ashley

Hi, I’m Ashley—the DIY-enthusiast behind this crazy blog!

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