What is it?
The Foundation Double Crochet stitch technique (abbreviated Fdc) is an alternative to the instructions at the beginning of a crochet pattern that tell you to chain a certain number of stitches.

This technique simultaneously creates a row of "chain" stitches AND a row of Double Crochet stitches (abbreviated dc) without making two passes. Basically, it takes the place of two rows of stitches: the "chain" row that makes up the beginning base and the next row of Double Crochet stitches worked into that row of chains.

As with our Foundation Single Crochet and Foundation Half Double Crochet tutorials, we are using " " around the word chain because this isn't REALLY a chain stitch but it LOOKS like a chain stitch when the stitch is completed.

Be sure to go check out our other foundation stitch tutorials:
How To Make the Foundation Single Crochet Stitch

How To Make the Foundation Half Double Crochet Stitch

Why Use It?
The primary reason we use foundation stitches like the Foundation Double Crochet stitch in our work is the elasticity or, more accurately, the consistent stitch tension, it provides at a hem, cuff, neckline or any beginning section of crochet stitches.

A crochet chain row tightens up significantly once the next row of stitches is worked into it because the loops of a crochet chain are made by pulling new loops through previously made loops. Since the chain loops are connected to one another this way, pulling on one of the loops by inserting a hook into the chain and making a stitch there tightens the neighboring loops. The result is a chain that is significantly shorter than we probably need and a fabric edge with little or no elasticity at all. And, unfortunately, even the almighty fix-all techniques in blocking will only get you so far… fibers only stretch so much before they are ruined or "killed" zapping them of all bounce and elasticity.

This unfortunate tightening of stitches doesn't happen when using the Foundation Stitch technique since the "chains" we make are connected to the stitch (Single Crochet, Half Double Crochet, Double Crochet, etc…) we create simultaneously on top of the "chain". The next "chain" we make is created by coming through the side of the previous stitch and does not affect the tension of the preceding or following "chains." 

Technique
Weaving in the ends on your knitting projects.

Technique
Weaving In the Ends On Your Crochet Projects

Technique
Four Ways to Block Crochet and Knit Fabrics

Let the grand experiment begin!

Ever since we have started creating crochet and knit patterns, folks have been asking us: