Is it necessary to perform ghusl again for Umrah after having performed ghusl with the intention (for ihram), then going to work, and then putting on the ihram garments?

Ablution (ghusl) for Ihram is a Sunnah, not an obligation, by the agreement of scholars, and the validity of Ihram does not depend on it. It is preferable for the ghusl to be immediately connected to the Ihram, but it is permissible to perform ghusl some time before it. This is the view of the Hanafis, Hanbalis, and Shafi'is. The Malikis, however, consider the Sunnah of ghusl to be conditional upon its connection to the Ihram.