Here's a general breakdown:
* Short Hair (2-4 inches): Dreads might start very short and stubby, almost like little nubs. They'll be quite tight and compact. The final length will likely be much shorter than 2-4 inches.
* Medium Hair (5-8 inches): This is a more ideal length for starting dreads. You'll have some initial length to work with, and the dreads will likely shrink up to 1/3 - 1/2 of your original length during the locking process. Your dreads might end up being around 3-6 inches long initially.
* Long Hair (8+ inches): You'll have the most length to work with. Even with shrinkage, your dreads will likely be a decent length from the start. Expect them to shrink by approximately 1/3 - 1/2 of your original length. If you started with 10 inches, they might end up around 5-7 inches long.
Factors Affecting Length After Dreading:
* Hair Type: Curly and coily hair types tend to shrink more when dreaded compared to straighter hair.
* Dread Size/Thickness: Thicker dreads might shrink a bit less than thinner dreads.
* Dreading Method: Different dreading methods (backcombing, twist and rip, etc.) can impact the initial length and how much shrinkage occurs.
* Shrinkage: All hair shrinks up to 80% depending on texture and elasticity.
* Maintenance: Proper maintenance is crucial for maintaining dreadlock length and preventing breakage.
In conclusion:
I can't tell you exactly how long your hair would be if dreaded at 15 without knowing your hair length beforehand. The best thing to do is to consult with a professional loctician. They can assess your hair type, discuss the desired dread style, and give you a more accurate estimate of the final length.