Current mental health statistics for US active duty and Veteran members justify research into the causes and remedies for those plagued with negative mental health outcomes. Recent research has suggested that the built environment is connected to our mental health. This study investigated this connection with active duty and Veteran populations across the US. A literature review was completed on what factors of light in the built environment affects mental health outcomes. An analysis of active duty and Veteran mental health symptoms and the natural light rating in their residence was completed to understand the design changes that can be implemented to positively mental health outcomes in their built environment. Finally, application of the results, the cost and benefits of designing and implementing built environment changes are discussed for positive mental health outcomes for our military personnel