moved into our house about 13 years ago - house inspector said house had termites in basement and seller then termite proofed - no problems for over 10 years - three yrs ago we had a swarm in the spring and i noticed about 1 inch of sawdust under a support beam in the basement - the beam extends under our den and it is about 10 feet in length - it also extends into the concrete foundation towards the outside of the house (in the basement)...
had the same exterminator for the last three yrs apply termidor treatment with the drillings into the foundation on the perimeter of the house ....

the beam in the basement now has extensive softness to it covering about 7-8 inches ....

what else can we do??? very frustrating to see lack of effectiveness on treatment - we live in northern new jersey - any help would be greatly appreciated....