Riddle me this (a/c quiesiton)

Why is flex duct not allowed per the fire resistant structure section (302) for garage installations, but building a return box out of wood is???
anyone, anyone??

and the attic ladder cover for that matter.

Cause that’s how we do it…:slight_smile:

Next question…

I think the reason balloon framing isn’t used anymore is because allowed the flame to spread to quickly. Now we use wood top plates for fireblocking, and wood is allowed in many other ares for fire blocking. I don’t think fireblocking, and fire resistant mean fire proof.