Least expensive installation?

[croghanite]

What is the cheapest way (up to codes and standards) to install a thimble through a wall and into a masonry chimney?

Would it be the stainless steel double wall pipe with 9" air clearance in the wall?

 

[daryl]

You can look it up in the NFPA211 and make a decision on what would work best for you. But check with your local codes, call a county or township inspector, sometimes the local fire dept handles this also. Your local hearth shop will also be able to help.