If you’re using a pattern with separate pattern pieces for the front and back of the pants leg, then adding the knee patches as you sew will barely take any time–certainly WAY less time than it would take to mend the knees and add the knee patches later!
The knee patches will reinforce the pants knees, so that they’ll be more resistant to wear and tear in the first place, and depending on your choice of fabric for the patch, they’ll add just another cute detail to what I’m sure is already going to be a pretty darn cute pair of pants.
How to Make Patches That are Built In
1. Cut out the pants pattern pieces as indicated in the pattern. The best part of this method is that you don’t have to do anything fiddly to your pattern!
2. Measure your kid’s inseam to just below her knees, and mark this on the pattern. For my kid, this is just about 13″ down. When in doubt, put the patches low–your kid will grow, and those patches will inch up before you know it.
3. Measure down from this knee mark to the width that you’d like the knee patch to be, and mark it. Add a quarter-inch on both the top and the bottom for a seam allowance, and draw a line straight across your pants pattern at both these measurements.
4. Transfer these marks to a separate pattern piece. Put a piece of scrap paper under the pants pattern at the knee patch markings. Mark the top and bottom points of the knee patch onto this paper, then trace the sides of the pants pattern onto it. Cut it out, and you’ll have a knee patch pattern piece custom-sized for this pants pattern:
5. Cut and prepare the pattern pieces. When you cut the front pants legs, use chalk to mark the location of the knee patches. When you cut the patches, iron down the top and bottom edges to the inside by a quarter inch. Use the chalk marks on the pants legs to help you position the patches onto the leg pieces, then pin into place:
6. Sew on the patches. Edge stitch around the perimeter of the patches, then sew something cute across the middle to prevent gapping–I just sew a big x from corner to corner, but something decorative would be even cuter.
7. Complete the pants pattern as instructed. Although… do you double-stitch everything when you sew pants for your kids? I double-stitch every single seam other than the hem and the waistband (this is how I like to sew elastic waistbands), because my kids are sooooo rough on their clothes.
Know what would also look cute with pants like these? Reversible cuffs with extra room to grow! I’ll show you how to make those in a few days.