Regular work at the stanard rate is work performed on the resource's work
calendar, the hours defined as his regular working hours. Overtime is work
done at hours other than those defined in his calendar. But Project doesn't
automatically apportion them. If someone's working time calendar says he
works an 8 hour day and you schedule him for 10 hours, Project sees this as
an 125% allocation and somehow your resource is magically able to do 10
hours of work in 8 hours of clock time. He's overallocated and you need to
fix it. In that scenario Project only pays him for 8 hours. To schedule
OT, as Mike said, you need to explicitly enter the number of hours of OT
that are included in the total work figure - just saying that the resource
is booked 125% doesn't do it.
For example, lets say your regular calendar is 8-5, M-F Standard calendar.
The calendar should ONLY list as work time those hours that are going to be
at standard rate so even if people occaisionally work on Saturday it should
be shown as non-working time in the calendar. You have a 6 day duration
task starting Mon 8am with Wally assigned to it. The tasl will be scheduled
to finish the following Monday at 5pm. But you're running a bit late in the
overall plan and you need it done a little sooner. It still 48 hours of
work, you can't change that and get everything done the task produces. So
you go to Wally and ask him to do 8 hours of OT on the task. You enter that
in the *schedule* by splitting the screen and in the bottom window entering
8h in the OT Work column of the Resource Work screen. Project does the
following -- 48 hours of work is required, 8 of which will be OT. Duration
is defined by the working time calendar, same as std pay. and OT work
doesn't count in duration and so the duration become 48h-8h, or 40 hours/5
days. Task now shows finishing Fri 5pm, just the reason you'd ask for OT in
the first place. Work is still 48 hours and the resource is allocated 100%
(not 125%) because work outside the resources working time calendar doesn't
count against his allocaton units either. Cost is 40h*StdRate + 8h*OtRate.
Project will evenly distribute those hours over the task duration, about
1.45 hours per day because as far as Project's schedule and budget
calculations are concerned it doesn't matter when those OT hours are worked,
only that they ARE worked. When you actually do the work, you enter
thehours per day the resource actually does in the usage view. If they're
going to defer the OT until Saturday, just enter the 8 per day they're doing
up till then. When you arrive at Fri it'll show you a day behind but
posting the 8 for Saturday will make everything come out right.