Sam if you are responding to comments made on a question you asked please do so in the 'Answer this question' box so that the original posters will see and can make sense of. Putting up a separate post has us all wondering what the first one was about - we get so many I can'tremember who asked what most of the time.

Is this the climbing plant that's against your garage? It won't have tree-sized roots, and shouldn't be a great problem. Cut it back to ground level and remove all of the top growth first of all - the thickness of the stem at the base will tell you roughly how large the biggest of the roots roots are.