Are Return Ducts Beneficial in Bonus Rooms

All,

I've got a question for you. I live in a two story home
approximately 2400 Sq ft. with a bonus room above the garage. The

This used to be called "a room above the garage". Someone named it "a
bonus room". big grin.

heating/cooling equipment is located in the attic. In two weeks, I'm
going to have the first and second stories split into separate HVAC
zones.

An additional issue I'm facing is the bonus room is either warmer or
cooler than the remainder of the house depending on the season. The

But the reason I posted is that you posted a week ago, and someone
asked you then if it was hotter or cooler than the rest of the house
during the summer, for example, and you post a second time, again
without giving that information. Why do you do that?

The room is warmer than the rest of the house in the summer. The
opposite is true in the summer.

I posted this message again, becuase it appeared it didn't go through

Well that accounts for why you gave no more info the second time. :)

the first time; nor, was I able to find it when searching the group a
few days later.

I saw it, plus several answers to it. Look in your outbox to get the
subject name you used, then search in groups.web-search.com or in your own
news reader.

Actually, since you don't post here that much, you don't need your
thread name. Your author name will do, in advanced search.

Few people get all posts, but some do better than others.

Your question below might seem to you as unrelated to this, but this
is the real world, not physics and mathematics for its own sake.

HVAC tech suggested adding a 12x12 return duct in the bonus room; in
addition to a previously existing duct in the upstairs hallway, to
help equalize the temperature. I read the return ducts should equal
the total size of the heating/cooling ducts in the rooms. So, if a
second duct were added in the bonus room, would the existing return
duct in the hallway need to be reduced accordingly?

Any information you can provide would be helpful. Secondary resources
would also be beneficial.

Normally yes.