Oh my. What is a passionate rose lover like you doing in that glacial hell hole? Reading about your endeavors has exhausted me and I haven't even lifted a shovel. I admire your grit and determination, but would love to see you rewarded with thousands of blooms on your rose bushes for all your hard work. I bet they could use engineers in zones 7 to 10!

Hold on RAVI! I am not sure if I understand it correctly. I posted what I THINK is how it works, but the guys on here may tell you I am wrong. I posted to see if I understood it correctly or not, but got what I think was a veiled insult from saltidawg, not sure if he intended that or not.... I ended up with the 2 stage, but I think it was knee jerk reaction to a price reduction my contractor offered me that made it seem like a good idea. I so excited that I got him to lower his price that I forgot the big picture and didn't ask him if he could also give me a better price on a one-stage (the 1-stage he had offered was a lower end, so I would have had to negotiate a better 1-stage). Therefore, I think I may be spending more than I need to and am HOPING the 2-stage was a wise idea. If price is the issue, get the 1-stage. Are you the guy where it was $1300 more? My quote from a large company here, was $1300 more for the 2-stage than the 1-stage. It ended up as a decent price for a package of work I was having done so I went with it. If I were just doing the hvac, I would not pay $1300 more for the 2-stage, with everything else the same. I think mike_home has some very good posts explaining everything. If you can afford it I think the 2-stage is nice to have, but not necessary. I have also read and been told that the 2-stage will help with the uneven cooling because it blows lower but longer. You might see if anyone responds to that claim, though I see you say they are larger rooms...can they add vents? Also, this may not be true, but my the salesman (claims he was a mechanic/installer) said that my furnace needs are between 80 and 100k so he is giving me the 100k because the blower will be stronger (they will and that should help with the cooling upstairs. I have 2 rooms that are usually warmer, they get the south sun that doesn't help either.That is sort of what you are saying with the cooling and the fan. Why does the 3.5 not get the rebate?

Mike, from the way the OP wrote, I assumed that the oversize issue is when a single zone calls for heat. OP, when you write radiant in floor, you mean pure resistance electrical heat? Will an insulation layer go under the flooring? How much head space do you have and how much will you loose? I have experience with finished basement in more Northern climes than Virginia. There was carpet on the slabs. Heated with hydronic convectors or forced air, the floors were always cold in winter. You wanted to have your feet up when sitting down. Radiant in the floor will be most comfortable, but won't be as responsive. It will be darned unresponsive depending on how it is installed. There may be lot of mass to heat up before air gets significantly warmer. I also have mini splits. In my home in the Gulf South. Run as programmed out of the box, the high wall units make very good ceiling heaters. As they throttle back approaching the set temperature, the blower slows down and hot air stratifies at the ceiling. You can combat this by manually keeping the blower fast or with ceiling paddle fans. Note that I have very cold floors in the raised house. A good mini split may greatly reduce dehumidifier use when cooling is desired, but there will likely be times when humidity will be high enough to support mold growth in shoulder seasons. If you have a mini-split, you might decide that a portable dehumidifier is tolerable. Portable dehumidifiers make a lot of noise, a lot of heat, and are energy hogs. You also have to empty them or rig up a condensate pump if no drain is where you need it. I have seen a portable dehumidifier make a basement uncomfortably warm in central New York Summers. They might work well enough for you in a basement laundry area. They can be placed remotely with added circulation with ducting. (See the link below.) I you feel that it will be cost effective, a ducted dehumidifier like a Santa Fe will work better. The Dept of Energy (Energy Star) rates dehumidifiers. IIRC, the portables are all about the same, but there is a big difference between them and the ducted models. Conditioning Air in the Humid South—Creating Comfort and Controlling Cost Research Report - 0214 November-2002 Building Science Corporation

What I wrote never said a heat pump won't work in a cold climate like Wisconsin. Houzz actually covered up my first post. Here's what I said...... (truth is stranger than fiction) Here's the rebuttal link to going with Fujitsu mini split option or any mini split for that matter. Don't forget to read the comments at the end of all of it... My opinion is it will be short lived if you go that route. There are furnace manufacturer's that provide life time replacement if the heat exchanger of the furnace ever fails. Typically minimum heat exchanger warranty is 20 years. Do what you want builders provide me with future work so take that for what it's worth. After a year or two... you won't get a builder to come back for servicing or repairs.