Driving home we wondered what condition the house would be in. Would it be freezing inside? Did the water pipes freeze?
Knowing that our house is well insulated and is a "passive solar" house design we didn't really expect the house to be that cold or to have any problems when we opened the front door.
When we got home it was 5:30 p.m, snow on the ground and the temperature outside at 0*C or 32*F
The wind cut through our jackets as we dashed for the door and stepped inside. WOW! So much warmer.
The house was 60*F or 15.6*C, a very comfortable temperature from outside and remarkable considering that there was no heat for four days. No one home to build a fire in the wood stove. No in-floor heating to keep the house comfortable. Our only source of heat was whatever the building was able to collect from the sun.
Lesson learned. Build facing south if you are in the northern hemisphere and add more insulation than the building code calls for. Our house has R60 in the ceiling, R40 in the walls and R30 under the cement slab. Our windows are triple glazed and most face south to allow the sun to warm the interior. A five foot roof overhang keeps the sun out during the summer. We are warm in the winter, cool in the summer.