Thank you for your question. I'm not sure I can answer your question without further clarification. The cable railing was part of a brand new custom home. I believe you are asking for the cost in reference to an addition. There are multiple factors that go into this particular job, and I would not be able to give you a number that would accurately reflect what your wanting. A contractor would be better suited to answer your question. This contractor was Bender Custom Homes. Please feel free to contact them directly.
http://www.benderchaffey.com/

If you would like an estimate for a project you currently have or may have in the future please feel free to contact our office at 1-800-851-2961. You may also visit our website at http://www.thecableconnection.com/ultra-tec.html