I'm building an addition that will cover the original tarra-cotta sewer pipe that goes out to the street. My question is should I replace the terra-cotta pipe with cast iron before construction?

I figure that I don't have to go all the way to the street, just a little past the new construction. Being that the terra cotta pipe is old, I'm worried that the pipe might collapse some day and I'll then have to tunnel under to fix it.

Linkback: http://www.plumbers.co.nz/forum/ask-plumbers-public/2/i-have-a-fifty-year-old-home-and-have-a-plumbing-question/421/

definitely replace the pipe! you will regret it once you have to call in a drain-unblocker that will end up telling tell you the blockage is due to a collapsed drain. To save cost replace it until you are outside the building envelope. All other pipe will remain accessible and can be sorted at later stage if needed. All the best!  Also Robbo is right just do it in PVC

i agree! also if you have trees around you will find that tree roots WILL find a way into that section of pipe, thats one of the biggest causes of blocked drains - either that or bloody tampons (which we as plumbers call mice!) haha