question about stove piping clearance

[aussieblake]

In our home the location we would like to locate the stove has a truss 17"-18" from the nearest edge to the combustible wall, running parrallel to the wall. These are manufactured trusses (spanning a long distance) so cutting and framing a support around them is not really an option. My question is regarding the clearance of double wall pipe to the combustible wall. Today in a conversation with a chimney installer, he casually mentioned the clearance for double wall pipe to a combustible surface was 6". Unfortunately I did not think of this question while I was at the stove shop, but if a manufacturer says for double wall pipe a 12" clearance is required from the back of the stove to the combustible surface, and the clearance for double wall pipe is 15" to the combustible surface. Is number to be used for layout of the vent opening in relation to the stove back? And if necessary can the double wall pipe offset closer to the combustible wall as long as it is not closer than 6" to the combustible surface? The reason I am asking is my wife is set on this location, and I would like to avoid offsetting towards the front of the stove(if possible), if it is possible and even if done close to the ceiling. Please let me know if this is unclear or you need more information, I have lots of experience running electrical conduit (wire twister for many years), but just trying to avoid more offset than is required and creating an unsafe situation. I understand the clearance requirement for stove pipes to combustible surfaces may change one AHJ (authority having jurisdiction) to another, but is the distance from the wall a "code issue" or a manufacturers installation requirement.

Does Double wall pipe come in other elbow angles other than 45 and 90? How about 30, 22 1/2, or 15?

Also if anyone knows of a stove that can meet these requirements without an offset, I am all ears! The Hearthstone Mansfield is close and the other Hearthstone models possibly better. But cost might be an issue.

Thanks in advance,

aussieblake

 

[begreen]

It's a bit hard to visualize, but yes, double wall pipe minimum clearance is 6" to the nearest horiz. combustible surface. Note that is the minimum, no problem going more than that. 6" double wall is available in 90 and 45 deg elbows.

There are several stoves that get closer than 12" rear clearance. The PE Alderlea and Quadrafire stoves for example and some Jotuls.