Matt wrote:

Just moved into new construction. Everything in the house seems to be
of average or higher quality, but the grass seed that they spread on
the lawn is coming in extremely clumpy. I will say that it was spread
in June and this has been about the hottest summer on record, but I've
also tried to water every night or morning at least for 10-15 minutes
per area.

Anyway, my question is whether the contractor grade grass seed will
eventually yield a nice plush lawn? Should I overseed with higher
quality seed or just not worry about it until this fall or next spring
when I can see what I'm really dealing with?

Never heard the term "contractor grade" grass seed before, but I assume you mean
it's whatever the landscaper put down - usually a blend of quick sprouting rye
grass and a slower sprouting fescue or bluegrass if water isn't a problem.
Hydroseeding usually gives a more even application.

One common mistake people make is to stop or slow down watering when the rye
comes in and not letting the fescue germinate. Doesn't sound like you are there
yet.

Seeded lawns usully do come in in clumps and it takes 2 or 3 years before all
the bare spots fill in. I'd wait until fall to see what you have. That will be
the best time to overseed.