After placing mullions on a curtain grid, you can control how they join at intersections. 
- In the drawing area, select a mullion. 
- Click Modify | Curtain Wall Mullions tab Mullion panel Mullion panel Make Continuous or Break at Join. Make Continuous or Break at Join.- Use Make Continuous to extend the ends of mullions at a join, so that they display as one continuous mullion. 
		
 
	 
- Use Break at Join to trim the ends of mullions at a join, so that they display as separate mullions.