Salam alaikum, 

There are some ethnicities that traditionally braid hair and sometimes with artificial material. In some countries, people say the ulamah have allowed extensions as long as the material is made of organic material (like cotton etc). But I've never seen proof of this position. Even though I don't live in those countries, hair braiding is part of my tradition. 

So, what is permissible to do in regards to adding material to the hair, not to deceive but because it looks better and has been proven to help hair grow. Also, I'm a single woman who is not in the process of engagement so I wouldn't be doing this for a husband or fiance or fiance's family.

In the name of Allah, the Most Merciful, the Grantor of Mercy

All praise belongs to Allah, and may prayers and peace be upon Allah’s final Messenger.

If the hair extension is not made out of hair and it is obvious to not be of her hair, then it is permissible according to the position of some scholars chosen by Imam Ibn Qudamah. The majority still forbids it and argue the hadeeth of the Prophet forbidding hair extensions didn’t exclude extension with non-hair materials. The first position is stronger.

Allah knows best.

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