Is it allowed to use Tajweed for other than Quran, like reciting Ahaadith of the Prophet sallahu alayhi wa salam or other than it?
“Some of the latter Scholars have mentioned in their Tafsir of His statement:
وَإِنَّ مِنْهُمْ لَفَرِيقًا يَلْوُونَ أَلْسِنَتَهُمْ بِالْكِتَابِ لِتَحْسَبُوهُ مِنَ الْكِتَاب
And verily, among them is a party who distort the Book with their tongues (as they read), so that you may think it is from the Book, but it is not from the Book
They mention that from this is a man reciting other than the Quran in the manner of reciting Quran. For example, for us to recite the Ahaadith of the Prophet sallahu alayhi wa salam like the recitation of the Quran. Or to recite the speech of the people of knowledge like the recitation of Quran. So it is not allowed for a person to chant speech other than Quran in the way the Quran is read, especially with/near laymen who do not distinguish between Quran and other than it except by tones and recitation “.
[Taken from here]
Faisal Ibn Abdul Qaadir Ibn Hassan