Have you ever wanted to learn How to Draft Trouser Patterns? There are more than 500 possible ways of drafting trousers, the waist can be high, normal, or low. The pants can either flare away from the body, hang straight, go around the butt or follow the whole silhouette. The length can go from micro to full and the leg shapes can flare more or less. There are endless possibilities when it comes to trousers, so how can you create that design you have been dreaming of?
Let’s start from the beginning. To draft the perfect pair of trousers you will have to follow these drafting steps:
In this post I’ll show you the process to draft any trouser foundation you want, but before doing that, there are a couple of technical names we need to address. These will be very important to correct the fit of our patterns.
The point where the leg separation happens. Where front and back patterns meet.
This is the distance measured from the waist line until the crotch line.
This is the distance around the crotch area, measured from waist to waist.
This is the length from the hip line until the crotch point.
The foundation refers to the upper section of the trousers that will shape the torso area. It sets the ease around the thighs and how comfortable the crotch will feel. There is 4 foundations: the Culottes, Trousers, Slacks and Jeans.
This foundation is based on the skirt pattern. It is the baggiest of the versions and has the deepest crotch depth, longest crotch length and crotch extension. Ease around the thighs should be around 15cm. This foundation can also be drawn using the A line skirt for extra flare.
The Trouser foundation is the one most drafting books come with. This design has a low crotch depth, similar to the Culottes. It also has a comfortable crotch extension and the fabric should hang straight from the abdomen and buttocks. The ease around the upper thigh should be around 9cm.
The Slacks are also known as Chinos. This type of pants has a slightly higher crotch depth than the trousers. In this case, the fabric should slightly shape your buttocks and hang straight from the abdomen. The ease around the upper thighs should be around 5.5cm
The jeans are the foundation that follows the shape of your body the most. The fabric should cup around your buttocks and hug your knees and ankles. There should be enough ease to allow for movement which translate to around 2.5cm around the upper thigh.
Here is a summary their main characteristics and a visual comparison of the patterns. These foundations can always be modified to go from one to another, it is just a matter of adding or removing ease at crotch and waist levels.
There is always a lot of confusion when talking about darts. Should there be one, two, none? How long should they be? And how wide? Well, I wish the explanation was easy but it’s not! Darts are a way to create 3D shapes on a 2D surface. All our bodies are different so it’s impossible to find a dart method that suits everyone.
If you take me for example, I have a flat stomach and a round buttocks. This means that if I add darts on my front pattern, this will create a round shape that my body cannot fill. Which will translate into extra fabric and wrinkles. The same way, if I have no darts on my back pattern, there will be no space for my buttocks. And if you add two darts, there will be too much shaping and wrinkles, so one dart is my sweat number. As a summary, all my foundations have exactly the same amount of darts: Zero at the front and one at the back. So despite what the book asks for, this is what I always go for.
The same stands for how wide and how long the darts should be. You’ll have to investigate through trial and error. In general, darts should point towards the fullest part and finish some centimetres before that point.
Once the patterns has been drafted, it is time to enter the prototyping phase. This phase is the most challenging to master and it can take between 5-10 prototypes (or more) to achieve the perfect fit. Each foundation will fit differently around the body, so always take that into account. For example, trousers are not meant to shape the butt.
I divided the fitting issues in two videos, before prototyping and after:
By this point your foundation should be ready and corrected, so the next step into drafting your design is choosing the waistline and the waistband. The waistline define where the trousers sit on the body and the waistband provides structure to ensure the trousers stay in place.
Most books define 3 main levels:
Remember that these are the main levels but you can make the waistline as high or as low as you want. These should be used as a guideline on how to modify the foundation to go above or below the natural waist.
Once you have defined the waist line, you can choose the type of waist band. There are 3 types of waist bands:
Which one you’ll choose depends on the body shape, your trousers design or how high or low the waistband sits on the body.
This is all the information and how to modify the pattern for each waistline and waistband can be found on this video too:
Once the foundations are clear, it’s time to define how long the pants are going to be. Every length has a name and they are patterned slightly different than the full length pants.
There are 7 official length variations:
When drafting these designs, you can use any of the foundations. No modifications are needed EXCEPT for the Short-shorts where the crotch curve has to be reworked in order to fit properly.
Be aware that these are the official lengths but you can always play around and make them shorter or longer. For example, shorts are too short for my liking and Jamaicas are too long, so I always go in between those two.
Once you have mastered all the other drafting trousers techniques, it’s time to go crazy with the shapes. You’ll notice that every foundation has its own leg line, some more flared and some less. There are 4 main silhouettes: Slim, Tapered, Straight and Flared.
For more information on how to modify the leg-lines, check out the following video:
If you tried my method and liked it, think about getting my ebook on how to draft trousers.
In there you’ll find all the information found here, in the videos and more. It is basically a recompilation of everything you need to know to draft any design you’ve ever dreamed of.
Head to my shop by clicking the image on the right and get it now!
