The exterior of St. Joseph Co-Cathedral is composed of pressed brick with stone trim.
 Two twin towers flank the main façade, which features a rose window.
 The roof is covered in terra cotta tile.

The main feature in the interior is the 34 foot (10.4 m) high Baldachin in the apse.
 Symbols of the Four Evangelists are carved into its upper edge.
 The same symbols are found on the columns in the church.
 On the dome above are found the symbols of the Tree of Knowledge, the Tree of Life, a snake, an apple, and peacocks symbolizing the triumph and glory of the risen Christ.
 The coat of arms for Pope Pius XI and Archbishop John Shaw of New Orleans are also found there.
 The stained glass windows portray the life of Christ and the seven Sacraments.
 A crest appears on all the columns with an emblem of faith, hope, charity and the Ship of Life.
 They are above a cast of grapes and wheat, which symbolizes the Eucharist.
The exterior of St. Joseph Co-Cathedral is composed of pressed brick with stone trim.  Two twin towers flank the main façade, which features a rose window.  The roof is covered in terra cotta tile.
The main feature in the interior is the 34 foot (10.4 m) high Baldachin in the apse.  Symbols of the Four Evangelists are carved into its upper edge.  The same symbols are found on the columns in the church.  On the dome above are found the symbols of the Tree of Knowledge, the Tree of Life, a snake, an apple, and peacocks symbolizing the triumph and glory of the risen Christ.  The coat of arms for Pope Pius XI and Archbishop John Shaw of New Orleans are also found there.  The stained glass windows portray the life of Christ and the seven Sacraments.  A crest appears on all the columns with an emblem of faith, hope, charity and the Ship of Life.  They are above a cast of grapes and wheat, which symbolizes the Eucharist.
St. Joseph Co-Cathedral (Thibodaux, Louisiana)