THE Q & A SERIES

HOW TO DO A FLAT BUTT ADJUSTMENT

Hi Emily,

I absolutely LOVE the Q&A series! Finding you and In The Folds has been a game-changer in my sewing journey!

One question which I'm struggling with finding much information about is how to do a 'flat seat' adjustment. I understand that a wedge needs to be taken out from the back crotch seam, but how is that actually done?

Appreciate any guidance you can give!

Thanks, Kimi
New Zealand

Hi Kimi!

Thanks for your question! Firstly, because I know this is a question that many people out there will love to get an answer to as well, but also because making clothes that fit is one of the foundations of In the Folds. Nobody wants to spend hours of their time (not to mention the money!) sewing clothes that don’t fit the way you want them to. And the thing is, with a little practice, these skills can quickly become second nature and just another normal part of your sewing process.

With the release of our Attwood pants pattern, it’s also a timely tutorial to cover in case someone decides their Attwood pants need a bit of adjusting.

However, it’s not quite as simple as removing a wedge from the back crotch seam. In last week’s Behind the Scenes post we discussed why we like to use industrial sewing techniques in our patterns, and I think this is another great example of the difference between professional fitting alterations and those you will find in the home sewing world.

While you might find that taking a wedge out of the back crotch seam gets the job done, it may cause fit issues in other areas and it will probably affect the finished look of the garment.

So, here’s a step-by-step tutorial for correcting this issue using professional fitting techniques so you know exactly how to do it! And, if you’re interested in learning more pants fitting techniques, check out our Pants Fitting pattern & Fit Kit.

HOW TO TELL IF YOU NEED A FLAT BUTT ADJUSTMENT

Also known as a baggy butt adjustment, you’ll know you need to make a fit adjustment to your pants because you’ll notice excess fabric in the back of the pants. You could even say that the back may look a little deflated and saggy.

You can check this easily by standing in front of a full length mirror, using another mirror to look at the back of your garment while being worn. Try to avoid using only one mirror to do this because turning your torso to look in the mirror will cause the garment to twist and will not give an accurate representation of the fit.

Technical drawing of symptoms of flat butt.

If the back is baggy and has too much fabric (Image 1), we will pinch out fabric vertically and evenly throughout the back leg and then add in any extra fabric that is needed at the waist.

PREPARE TO MAKE THE ADJUSTMENT

While wearing the garment, roughly pinch out the excess that needs to be removed in the butt area. (Image 2, below). You may need someone to help you do this if you’re trying to fit them on yourself! We’ll remove fabric throughout the whole leg evenly to stop the pattern from skewing.

Take the toile off and pin out vertically through the whole leg (Image 3), making sure to take an even amount. Unpick side seam at the waist and add in fabric if necessary (Image 4).

IN THE FOLDS PANTS PATTERNS & RESOURCES

HOW TO DO A FLAT BUTT ADJUSTMENT

Step 1

a Draw a line from the top to the bottom of the pattern parallel to the grainline roughly in the middle of the pattern. Make sure to avoid the dart. Let's call this line A.

b Draw another line parallel to line A. The distance between the two should be the amount you'd like to remove from the pattern. Let's call this line B.

Step 2

Add an 'anchor line' perpendicular to lines A and B. This will help you line up the pattern.

Step 3

Cut through line B completely and overlap, aligning line B with line A. Use the anchor line to help realign the pieces. Tape in place.

Step 4

Taking from the pattern evenly means we've also made the waist and leg measurements smaller, so it's likely you'll need to adjust the pattern to add the amount that you took out through the whole leg back to the waist area only to return the waist measurement to the original. We will spread the amount we are adding to the pattern between the CENTRE BACK and the side seam.

i Record the amount you took from the pattern overall, (see STEP 1 b).

ii Divide the amount from (i) by 2 so we can add it evenly on each side.

a Mark in the distance found in ii, out from the STITCHLINE at both the CB and side seam.

Step 5

Re-draw the side seam and CB seam with smooth lines, joining them back to the waist STITCH LINE (a) and CUT LINE (b). Cut off excess paper. Check all seams are the correct length by 'walking' the pattern pieces, as if you were sewing them together.

I hope this helps you get the fit you’re after, and don’t forget to check out our Pants Fitting pattern and Fit Kit for even more in-depth tutorials just like this one!

Happy sewing,

Emily

RESOURCES MENTIONED IN THIS ISSUE

The Attwood pants pattern is the August 2023 project for our Curated by ITF membership, and can be purchased here, or after August by current members in our Past Issues section. More information about the subscription can be found here.
The Pants Fitting pattern + Fit Kit was released in 2023 as part of our Pants Sewing series. It is currently only available to members of our Curated by ITF subscription, but will be released soon as a standalone resource in our online shop.
Checking patterns: Curved seams - blog post here.