Question
My neighbors cypress tree roots have grown under my driveway and totally destroyed it.  Had to replace it a few years ago.  It is now growing under my house and cracking my slab and garage.  How do I stop this, hopefully without killing the tree. When we replaced the driveway I was amazed at how many roots were under my driveway.

Answer
You did not say how close the tree was to your house. You can cut up to about a 1/3 of the roots and not seriously damage the tree. I would trench along the land line or the away form the tree between the tree and your drive and house or along the house. I would not let the roots damage the drive or possibly the foundation. Trenching along the property line will stop the intrusion of the roots your way. Conifers recover form root cutting better then hardwoods so there would be little damage to the tree--may get some dieback of foliage on the cut side but the tree will recover. The roots are in the first 2 feet of soil so you will need to trench that deep. You can rent a trencher and this would make the job easier.