If you are ordinarily resident in the State, the minimum age at which you may marry is 18 years (unless you have a Court Exemption Order). This is the case even if you marry outside of Ireland. Even if you are not ordinarily resident in the State, you must be over 18 years of age if you wish to marry someone in Ireland.
There is no requirement for parental consent to a marriage, irrespective of the ages of the parties concerned.