In the christian belief, it isn't the building that is the church; A church is the body of believers, who meet within the building.

Something to do with the church being "God's House" Jesus nick-named Peter "The Rock." He told Peter that he would be the cornerstone upon which the church would be built. The church is not a building, rather it's the people that follow Christ. We are the church

Church Office Building was created in 1972.

Church Administration Building was created in 1917.

To a Christian a church building is only a place to meet. It has no special significance. For example a church building is not the place where God dwells.