regex to match repeated consonant

Question

How can I detect with a regex expression if the same consonant is repeated three times or more?

My idea is to match words like tttoo

Answer 1

This is about the shortest regex I could think of to do it:

(?i)([b-z&&[^eiou]])\1\1+

This uses a regex character class subtraction to exclude vowels.
I didn't have to mention "a" because I started the range from "b".
Using (?i) makes the regex case insensitive.

See a live demo.