Installing ceiling boots (basement hvac)
 

I am working on basement mechanicals

I need to install 6 hvac boots, 5 - 12x4 x 6" and one 4"... and few
wyes8x6x6

All joist installed with 24" span .

I intend to rivet 2L shaped tin pcs something like 7x1 and attached it
to each
side of the boot. Should I offset those ears, by 1/2" like outlet
boxes?

Thanks.

Installing ceiling boots (basement hvac)
 

Hard to understand your question ...but the boots should mounted so
that they will extend into the sheetrock that will be later added...1/2
to 5/8 inch below the joist or truss