I use to keep track of yardage and found between 10 & 20 yds. for a full size quilt with about 18" drop was about it. Depending on the pattern and how many different colors needed. Making quilts are not always cheap.

Does it have small pieces, and lots of them? Each seam eats up 1/4" of fabric. So, for example, if you have (4) 3" squares to join into a 4 patch, you 'lose' 1/2" of fabric, that is, 1/4" per piece for each seam. Your 4 original 3" squares are now 2.5" when sewn together. (This assumes that the 4 patch will be sewn to another block of some kind.) Repeat this often enough and the actual visible fabric in the quilt is significantly smaller than what you start with.

There is - if you are lucky - enough fabric to get you through a few mistakes, and for the dreaded 'waste' fabric, that we all call 'scraps'. Even so, 14.5 yards of fabric seems like a lot.

That's my theory and I'm sticking to it.

Oh my gosh ladies! Thank you all for your comments....
I did contact the pattern designer and asked her why the pattern called for so much yardage. It's Mad About Plaid by Lyn Mann. She said that if I use scaps it will take more yardage, but if not I could get away with much less fabric. Doesn't really make sense as yardage is yardage. But what do I know?
There are a lot of small pieces as many of you asked, so I assume that accounts for a lot. I also think it's the method Lyn uses in putting pieces, or blocks together that requires so much extra fabric.
Thanks for all your input. It's nice to know that within 24 hours I can have the answers to my quilting questions! Thank you, thank you, thank you all!

The pattern is Mad For Plaid by Lyn Mann. I do not have a link however.

I didn't find Mad About Plaid, or Mad For Plaid but did find a couple other Plaids by Lyn Mann ....
http://quiltsbylyn.com/patterns1.htm

Her Plaid Madness looks like it would take a lot of fabric.
So yes, the large amount does look possible.
As mentioned already ... she may also be giving a good overage to allow for any "oops" moments.
Better to have too much, than to be fretting one is going to be short.

Welcome to the QB and Good Luck!

I agree that your pattern may require 14 half yards of each fabric. What is your pattern?

What I suspect is going on with the yardage for scraps is that each fabric purchased will have a certain amount that is not used, and the smaller the amount of fabric used in each fabric purchased, the larger the percentage of unused (left over) fabric will be.

For example: suppose you are making a quilt with just a small set colors and need 340 4"x4" squares divided among four colors. Using the calculator that mindless posted, you need to purchase 1 yard of each of those fabrics. Now suppose you want a scrappy look for your quilt and are using many different fabrics, so that you need those same 340 squares divided among 20 colors. The same calculator says you would need to purchase 1/4 yard of each of those twenty fabrics, leading to a total yardage of 5 yards (vs. the total yardage of 4 yards when using only 4 colors). (Also note that when you are cutting a 17 4" x 4" squares from a 1/4 yard, you get 10 squares from the first 4" x WOF strip, and then cut 7 from the second strip, leaving you with a 15" x 4" strip left over, plus a 1" wide strip. These left overs are where the seemingly "extra" yardage is going.)

Playing around with the Plaid Madness quilt that QuiltE found (which may or not be the same as the quilt pattern you purchased), I calculate that a quilt measuring 68" x 90" quilt made up of only the central squares pictures (meaning no borders, either plain or pieced), it would take 10 yards of fabric, if using only One color. It's a little hard to tell exactly how many different fabrics are used in the pictured quilt, but it looks like at least 30 to me, which would definitely drive the yardage needed up quite a bit.

How many different fabrics does your pattern call for?

Wow! Plaid Madness looks like a challenging pattern. That quilt has a million pieces. I hope you are not new to quilting.

Good luck with it.

bkay ... TBH I don't think it would be that challenging as far as what to do and how to do it.
Though the challenge (to me) would be the repetition of making the two elemental blocks,
again and again and again and again and ..................

I would get so bored and fed up with it all.

On the upside, the quilt assembly would be quite easy, with all straight/square blocks to join
again and again and again and again and again and again and again ................

Though as an intermittent scrappy quilt, it would be a good long term project!!! :D

I haven't read all the replies but I'm wondering if matching up the plaids is part of the reason why you need so much yardage?