It's more likely a problem with the heating system but if that checks out you might try an energy audit with a thermal imaging device. Call your local energy provider.

The condensation could be from excessive moisture in the house but in a very cold climate the source shouldn't be difficult to find. Start with the bath and kitchens and make sure the exhaust systems are working. A poorly vented gas fireplace, boiler or furnace can also produce excess moisture, CO2, and CO.

I really doubt this is an insulation problem.

A better description of the condensation on the windows would be helpful. In between the panes and you have a window problem.

Do you have a humidistat?

Most of the time you don't feel as comfortable at a particular temperature is humidity or drafts. Drafts you would think you could feel. If you have large air infiltration, then it would be dry and you would feel colder at the same temp. Air infiltration could be from caulk that has dried up.

The basement temp would likely have nothing to do with batts but it does depend on construction technique.

have your heating system checked out if you have not done so already.
Moisture on the window is from high humidity levels typically. His suggestion to crank a window will releave that, but its a really bad suggestion as it should not be necessary. A window supplier should know the reason for condensation on the inside of glass.
does your house have an air exchanger?
I responded your to ICF question you posted some time ago, FYI. not sure if you saw that or not.

How long has it been since you changed the filter on the HVAC system? Had it serviced? Have you had the ductwork checked to be sure that it's still properly attached? Are the baths and kitchen actually externally vented? Damp air at 68 degrees feels much clammier and colder than does dry air at 65 degrees. If you have condensation against the interior of a window, you have a humidity problem that needs to be solved. Start with how the basement was waterproofed. Get a hygrometer or two and place them in various areas around the home as a first level diagnostic. Go around to every single one of the HVAC ducsts and measure the temperature and humidity of the air coming out. Do the same at the intakes. If you'll do the grunt work, you'll make it easier and cheaper for when you call in the pro.

This is a HVAC problem, not an insulation problem.

I change the filter regularly--every season if not more often. The kitchen and baths all have vents (unrelated my one bath fan "rains" when we have a blizzard as snow gets in and melts and pours into our bathroom to the point I need a bucket). Builder says that is normal b/c wind blows the vents open:) We have had HVAC problems. Our air conditioner has quit several times. Both times they told me basically I'm a dumb blonde and that it was not working b/c I was putting in "too expensive of filter" so the unit couldn't get air. I put in the high end allergen ones. So I put in $1 ones and it still stopped working. They figured out the copper tubing feeding antifreeze had a tiny crack. They saudered it. Next season, it happens again and they try to give me the run around and I tell them I think it is the pipe again--it was, they sautered it again. My hot water heater also quit b/c they installed the vent upside down outside (which I had to tell them I thought that was the problem--my dad figured it out by me telling him about it over the phone). My oven vent didn't work b/c they didn't punch a hole through the duct work to connect it. My dryer quit b/c they just shoved it up against the duct work and it wasn't connected. I have ripples in my roof that they tell me are normal (even the shingle rep who I demanded come look at it says it is normal?). We have kids who splash in the tub a normal amount, and the ceiling in the basement below the bathroom got a huge water spot on it-still don't know how it was getting to the basement ceiling (and the a**hole drywaller left 3-4" of mud on the side walls out of sloppiness that I got to clean up along with hunks in the carpet) which I did inform the builder about. Also they ran the drain for the gutters (the underground tube) right in front of the house so that I had a pool of water constantly in front of my house--like a swamp and my sump ran non-stop. They had to come move that 10' away from the house at my insistence. So fed up....

The condensation is on the inside of the windows. The window supplier told me it was b/c the house has not dried out yet from being built. We do not have a whole house humidifier or an air exchanger. lzerarc I am very appreciative of your ICF response and it is something we are seriously considering for a future build although with the level of incompetence I've encountered with this house, I seriously feel like getting a home built without major defects is close to impossible. Our previous home was built in 1925 and we never had any problems. I am so appreciative of your responses--I read who had responded and felt like I got the opinion of the "heavy hitters." I guess my main concern is carbon monoxide (we have a monitor). Is this something that would be covered under the furnace warranty or should I have a company that did not install the furnace come look?

Using a different construction system next time is fine but it would not have helped you with your current house because the problem is obviously incompetent dishonest contractors.

Next time find a competent honest contractor and/or hire an architect to provide you with a good design and construction quality control and assurance. What is the point of saving that fee if the house is a nightmare to live in?

Agreed Renovator8. Just for background--we moved 6 hours from "home" with an infant, had a limited budget and 3 days to find a house (we looked extensively for 6 months online). We put an offer on a different house and got no response so we bought this house at the last minute (it was a new model with a reputable builder who did 5-10 homes a year and had lots of "upgrades" from typical model homes) so what could go wrong, right? :) Builder has been very responsive to all of the problems even outside the year warranty, but just has subs that are idiots. I guess this is how you learn and it has made me much more interested and involved with the process for the next go around on a positive note:) For a long while I just believed them that I was an idiot and that all those things were normal...even now I guess I just assume to have that many problems with new construction...so if anything has made me much more self-assured to chew a** if need be....just gets old! I remain very appreciative of finding a place that I can ask questions and get answers from people who have vast knowledge in the field.

I agree that the hvac system is not working properly.
if previously the house was comfortable & didn't have
the condensation issues at the windows..then something
has changed with the system.
testing ducts for leakage & mastic sealing them is a
good investment. energy raters & some auditors do this
type of work. less value is utility company audits as they
do not achieve the level of savings that raters require.

condensation on windows is a Relative Humidity (RH) issue
adding a stand alone dehumdifier will help to lower
RH in the house. home depot and lowe's carry these
dehumidifiers for a couple of hundred bucks.

best of luck.

It is the builder's fault that he uses these subs. A lot of what makes a good builder is the quality of the subs he uses.

3 years in - my issues - some of our trim had the wood grain come through the paint after some time. I had the builder re-paint once and I paid $100 for someone else to redo it. We needed some door adjustments for settling which the builder did even after a year. One of our deadbolts broke and we had some problems with it early on - fixed for free after a year. I paid $300 to have a new drain system put in for the upstairs a/c that was easier to clean out as it got plugged and shut the system down. Replaced a window with condensation under warranty but I had to paint it (3 years). The dishwasher drain was pinched and had to be fixed first week.

I think that was it which I consider perfectly acceptable. What you have dealt with is not.