Tahiyyat-ul-Masjid and the supererogatory Salah for Wudu'

Q 5: Upon entering a certain Masjid (mosque), I am used to offer two Rak`ahs (units of Prayer) intending them as tahiyyat-ul-Masjid (two-unit-Prayer to greet the mosque) and the Sunnah (supererogatory) Prayer of Wudu' (ablution). Is my Salah (Prayer) valid? I heard that upon entering the Masjid I should offer Tahiyyat-ul-Masjid first.

A: It is permissible to offer Tahiyyat-ul-Masjid then the Sunnah Prayer of Wudu' as it is permissible to combine them in two Rak`ahs.