"sprtan" wrote:

While building my home, I was recently asked if I wanted to have a
natural gas driven back up power generator installed? Ostensibly to
provide back up power in the event of an outage.

My first question is whether or not anyone sees value in this.

Well, that really depends on where you are building and how reliable electrical
service is there. And how much loss you might incur from food loss. What are the
neighbors doing?

Secondly, does it really matter whether I have it installed at time of
building or can I have one installed at a later time.

The savings is the wiring and switching required. They get done when the walls
are open and only require one inspection. Do it later and that part is more
expensive and require reinspection. If its that common, get all the
wiring/plumbing done, but save the purchase of the generator for later.