HeyBub wrote:
I just had a conversation with a chap who's putting more insulation
in his attic. I jokingly reminded him to start at 3:00 a.m. to avoid
the 135°F attic temps we've been experiencing locally.

He said "Nah, no problem. I disconnect an A/C duct and let it cool the
attic. Gets it down to about 80-85°. I re-tape the duct when I'm
done."
After reassembling the parts of my exploded brain, I calculated he
might be on to something...

I worked on a group-build of a church on a scorching hot day. It was a 48
hour build. Start Friday night and finish on Sunday night. Foundation and
concrete floor in, and the entire building built on the slab, brick
exterior, roof, drywall, carpet, heating & air conditioning all done in 48
hours.

Once the roof was on they started installing the HVAC. It was so hot that
once they had the evaporators installed and the power on, they got the AC
running before the drywall was up and the doors and windows installed. It
was soooo nice to have some cool as I was working intalling vacuum pipes on
the freshly drywalled and still wet mud on the ceiling before the T-bar guys
got started.