I am sorry I did not see your question last week.
A lot of people in Canada grow orchids in your conditions.
Your temperature is not a problem except for new purchases. Lossing buds is a problem in the winter. After they get established they should do fine.
Your house conditions are fine for growing the orchids. You will only have to see they get enough sunlight to bloom.
Measuring light levels with an SLR camera
measure the light levels and place each type of plant where it can get enough light. You can move them outside for the summer if you want. You will have a short growing season, so plants that bloom multiple times a year may only bloom once for you.
Start with easy orchids. The Phal should do well for you and next time it should not drop the buds. Dendrobiums are another easy to grow orchid.
If you want to try some cattleys near the window, pick the semi-minatures that do not grow over 8 inchs. They will be easier for your space.
Ask more questions when you are considering specific plants.