Adding central AC

[auggie]

We have a small ranch and are considering adding central air in the near future.  But- we are also hoping to add a second floor, though the time frame on that is not too solid.  Should we wait and just add AC when we do the second floor? If we do it now, would we have to buy a larger ac unit, or a second unit, at that time?  

Does anyone have any insights on the pluses/minuses of waiting vs. going ahead with it now?

[Deleted]

We have zoned HVAC and I really like it. We aren't upstairs much during the day, downstairs at night. I can set seperate programs. I don't have to heat/cool the floor we aren't on just to get the floor we are on comfortable. You can run both floors from the basement. We choose to put the second floor unit in the attic. First floor ductwork is ran in the basement joists and registers are on the floor. The second floor ductwork is run in the attic and the registers are in the ceiling.

[auggie]

Jul 18, 2013 22:13:37 GMT -5 rehabaddict said:

We have zoned HVAC and I really like it. We aren't upstairs much during the day, downstairs at night. I can set seperate programs. I don't have to heat/cool the floor we aren't on just to get the floor we are on comfortable. You can run both floors from the basement. We choose to put the second floor unit in the attic. First floor ductwork is ran in the basement joists and registers are on the floor. The second floor ductwork is run in the attic and the registers are in the ceiling.

That sounds nice.  Can you have zoned AC off of one unit or do you need to have two?

[Deleted]

Jul 18, 2013 22:23:01 GMT -5 auggie said:

Jul 18, 2013 22:13:37 GMT -5 rehabaddict said:

We have zoned HVAC and I really like it. We aren't upstairs much during the day, downstairs at night. I can set seperate programs. I don't have to heat/cool the floor we aren't on just to get the floor we are on comfortable. You can run both floors from the basement. We choose to put the second floor unit in the attic. First floor ductwork is ran in the basement joists and registers are on the floor. The second floor ductwork is run in the attic and the registers are in the ceiling.

That sounds nice.  Can you have zoned AC off of one unit or do you need to have two?

You need two.  Two furnaces, two condensers.  They would be smaller than one needed to feed the whole house.  Also, if you install one now and plan to add to it, make sure you are doing your research.  Oversizing units, even for a few years, increases the humidity level in the house.

Also, be very selective of where the outside condensers are placed. Our old hose had them right by the patio and they were so annoying when they kicked on.

[kaylie]

My inclination would be to wait. Both adding a second story and adding central AC are messy/expensive projects. My guess is that it would be cheaper and easier to do it at the same time.