When I worked in a warehouse in a northern state, they kept the bay doors closed when there was no truck there, and even when the doors were open, they were covered by strip curtains to help keep the heat in.
Even when it was below freezing outside, it was warm enough inside the warehouse to walk around in an insulated shirt and no jacket (~50 degrees inside, ~20 (or less) outside).
Of course, they didn't do it for the employees, we dealt with a lot of food products that couldn't be allowed to freeze. So climate control even in a warehouse is possible, but maybe not cheap in 95+ degree Sacramento summer days.