I could use some advice on the best way to increase airflow to the far side of the house. My furnace is all the way on one side of the house in the basement and the 2 bedrooms on the opposite side of the house on the 2nd floor are always hot in summer/cold in winter. The hot summer issue isn't a huge deal since we've gotten new windows and installed ceiling fans in those rooms, but I'm having a hard time keeping them as warm as the rest of the house in winter. I'm sure it doesn't help that they are above an uninsulated garage and the ducts all come from an unfinished basement with minimal insulation. It's probably also worth mentioning I live @ roughly 6000 feet and humidity is very low.
With our old furnace that always ran @ 100% the problem wasn't as bad. With this new multi stage system it seems when the furnace is just cycling on to its lowest stage that there is barely any air coming out of the vents in those 2 rooms and the air coming out in those rooms barely even gets warm. I've put together a list of options that seem to me will help the situation and wanted some professional opinions on whats the best way to proceed.
1 - If possible, can I eliminate the lowest stage of the furnace? So even on its lowest setting the fan will push more volume of air?
2 - Fans - Are those inline fans that go into the duct worth installing? I've identified which 2 ducts feed those 2 rooms from the basement. They are easily accessible. Will I have issues with those fans turning on and off via the furnace control in one of these variable speed setups? Probably need some kind of relay in there?
2b - If I finish the basement and one of those fans were to go bad, it would be a huge pain to get to them. Are they fairly reliable?
2c - Are those cheap fans that go on top of the register worth checking out as an alternative?
3 - For one of the bedrooms in question it would be pretty easy to get a return line into, on the down side it would be in the closet. Is it worth putting a small return in the closet?
4 - Should I wrap the ducts in the basement with insulation?
5 - The garage beneath these rooms has no insulation on the outside walls or the doors. There is at least insulation between the bedroom floor/garage ceiling. How much will I gain by insulating the garage?
6 - I've closed several vents on the main floor of the house in hopes of getting some more flow upstairs but it doesn't seem like it helped. Am I causing more harm than good by doing this?
Sorry to puke so many questions on my 1st post here, but I'm at a loss for what to do next. I've got what I believe is a high end furnace and very good new windows but my kids are still freezing @ night. Any insight is greatly appreciated!