Carpenter ant flies
What do carpenter ant flies look like? Are they dangerous to house structures? If we have them, what can we do to stop them? We would prefer non chemical means?
Loudoun County Virginia insect issues
Carpenter ants are described in this Extension publication. https://extension.umd.edu/hgic/topics/carpenter-ants
In order to offer you a safe, research -based recommendation I would recommend that you bring a sample of several (whole) insects to the Loudoun County Extension office. No chemical recommendations are advised until the insect in question is correctly identified. The office is location in Leesburg.