Stainless pipe through floor joist question

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racer765

New Member
Oct 5, 2023
8
Michigan
Hello everyone,
I have a question regarding stainless pipe passing through floor joist space before I finish the chase. I recently had a bad block chimney removed and have installed stainless pipe in it's chase. The woodstove is in my family room in my basement and the pipe travels through the floor joist through a framed in first floor chase to the attic (single story home with walkout basement). I installed the pipe following the manufacturers instructions with the ceiling support in the basement and insulation shield/firestop in the attic. I may be overthinking it but should there be a joist shield in the joist space along with the ceiling support? The pipe has a required 2" clearance to combustibles which I have 3" to the closest combustible which would be the floor joist (firestop drywall in the chase also has 3" clearance to the nearest point). I fabricated a shield I think would help reflect radiant heat back to the pipe in that wood floor joist space but maybe it is not needed with this setup (pictures with and without my fabricated shield).

The joist shields state "The firestop joist shield is used in floor & ceiling penetration installs that do not include a ceiling support" which would indicate it should be ok without a shield?

Thank you!

Chimney 1.jpg Chimney 2.jpg
 
3" is ok. It looks like the closest clearance is with the box framing of the chimney support, which should be no closer than 2".

Hint: It's ok to put a vent grille at the top of the chase to scavenge some heat from the chase. If one is also added at the bottom of the chase the air will convect through the chase. 4x10 grilles will suffice.
 
3" is ok. It looks like the closest clearance is with the box framing of the chimney support, which should be no closer than 2".

Hint: It's ok to put a vent grille at the top of the chase to scavenge some heat from the chase. If one is also added at the bottom of the chase the air will convect through the chase. 4x10 grilles will suffice.
Thank you!! Yes, you are correct. I double checked the box framing, 3 sides are 2 1/4", the support in the back you can't see in the picture is direct to the beam a little closer at 2" exact.

I like the idea of the vent grilles, I will definitely add them.