Complex sentence: A major renovation was completed in April 2006, including a new geothermal heating system, as it previously was poorly climate controlled, and now also houses a SUNY Plattsburgh lecture hall.
Split into simpler sentences: A major renovation was completed in April 2006, including a new geothermal heating system, as it used to have poor climate control. It now also houses a SUNY Plattsburgh lecture hall.