Question
I have a large tree about 5 feet from my house.  I was told that I should have the roots cut and a barrier wall installed to keep the roots from interfering with my foudation

Answer
It will depend on the tree species. My gut feeling is if this tree is large and there is no sign of any damage now i would not think there will be any. The tree has grown its root system away from the foundation. Five feet is too close to a house for a large tree BUT it will depend on what species of tree this is and the type of foundation. I would recommend if you are in the US to contact the State Forestry Agency and ask one of their Foresters to come take a look (this is a free service). You could also hire an Arborist to check it out--make sure the Arborist is certified. Here is the web site of the organization that certifies the Arborist.

http://www.isa-arbor.com/findArborist/findarborist.aspx