Swarming inside the structure...

Swarming inside the structure indicates that a colony already exists within the home. When termites swarm to begin new colonies, the wings of the termites that do not survive fall off when the termites drop to the ground.

Swarming that occur outdoors is not an indication that buildings are infested, however these termites that live underground tunnel up for food, which could include the structures.

Tunneling...

Termites build pencil-sized mud tubes for their travel from their nest to their food source.

Damaged wood...

If wood is termite damaged, you will hear a hollow thud when it is tapped with a hammer. If it is picked and probed with a pen knife or screwdriver, you will see tunnels running parallel with wood's grain. Other signs may include buckling paint or tiny holes on wood.