The presence of the winged reproductives indicates an active colony 4 - 10 years old somewhere nearby. The colony may be in the house or in some wood outside. Mud tubes on the foundation, if they contain live termites, would indicate and active colony attacking the building. Either finding would be cause to call a pest control professional to evaluate the situation. Termite tubes on wall surface To determine if the insects found are actually termites you can take a sample to your county Extension office for proper identification.
Termites create tunnels in wood.
They prefer soft grain, spring growth wood or damaged and decaying wood. They will feed on dry lumber as long as the moisture from the ground is adequate. To increase the moisture level in the wood the workers may bring mud up from the soil and pack it in the tunnels. The presence of mud in the tunnels indicates the tunnels were made by termites and not by carpenter ants. Carpenter ants leave clean, smooth tunnels.