My grandmother used to shut off the water, drain the pipes, and shut off the heat when she went to visit relatives for a few weeks. We’d bring her home on a nice sunny 50 degree day and it would be bone chilling cold in the house. Easily down in the thirties. Any water left in glasses would literally be ice.
I’ve always blamed the insulated walls. The house cools down during the long cold nights (lower 30’s). A few hours of sunny 45 to 50 degree daytime warmth doesn’t have enough time to penetrate the walls and do much good. It’s more miserable inside the house than outside in the sun.
Thats just a common sense answer. Whats the science behind a unheated house?
Every once in awhile I see a news article claiming a fed up homeowner shuts off the heat to save costs. I can’t see anyone surviving that. Once the house is cold then even on a mild day its freezing inside. The house never warms up.
I don’t think it’s possible for an unheated home to be colder than the average outside air temperature, but it’s certainly possible for it to be much colder than the daytime outside high temperature. It’s also possible to design an unheated house to be much, much warmer than the average outside temperature, using passive solar heating.
It depends. It depends on the high and the lows. The old ranch house that I grew up in would be about 1 degree warmer than outside in the morning before the heater was turned on. And if the heater was not turned on it would warm up with outside air temp. It was a 200+ year old slat board house. No insulation and a lot of drafts.
NOw a newer home would be different. If it had good insulation its temperature could be above or below outside. If there are several days with no or little sun load the house could cool down. Heat will travel through any insulation the amount will depend on the temperature differance and time. On a long freezing night more heat can escape to outside. If the day does not warm up and is overcast the house will not reheat. The next night or cold spell more heat goes out of the house. Until the house inside temperature is close to the outside air temp. The next day when the sun comes up The air is heated up and heat will radiate off the ground to the air. But if the house has good insulation little heat will travel through the walls to warm up the insides(the air, floors, furnature, and anyother solids.
Also if you go outside on a sunny day the air can be cool but you are recieving heat from the directly.
It would be interesting to setup a temperature recorder in a house. The type that charts the temp over time on paper. Turn off the heat in a modern, insulated unoccupied house for a week and see what the chart looks like on the last couple days.
We had a massive snow/ice storm Christmas day 2012. Lost power while I was watching tv at 11:45pm. I got up at 8 and my wall gauge in the living room was at 52. The house lost 20 degrees in 8 hours. The insulation helped a lot but by the next day I’m sure it would have been 30 in there. I hooked up a couple vintage gas space heaters and stayed warm until the power came back a week later.
I know here, we typically have low 30’s to high 20’s at night. By 10 AM it’s warmed to low 40’s. On a sunny day it might reach 50 by 1PM. Then start cooling down at 4PM as the sun sets at 5.
That’s roughly 14 hours of low 30’s, 7 hours of low to mid 40’s and 3 hours of 50’s. Not a lot of time to warm up the house.
btw, those temperature observations are from freezing my butt off on a deer stand from dawn to dusk in mid Nov. As the day goes on I shed my outer jacket. Then if it’s a sunny day I can shed my warm vest after it gets to 50 in the early afternoon.
Any hunter is aware of the temperature swings throughout a winter day.
One thing I’ve noticed with my house is the way the indoor temperature of my house lags what I “intuitively” think it ought to be. It is coldest around 9-10 am, and warmest at about an hour after sunset.
As for the actual average temperature inside vs outside, I think every house will have a different answer that will vary both with the house and the surroundings. My house is in shade until about 10-11 am and we’re also in shade starting at about an hour before sunset. I also have two strategic deciduous trees that give the house more sun in the winter than the summer.
Not directly relating to houses, but concrete block warehouses full of furniture will get cold and STAY cold for several weeks. I used to work in a furniture store that didn’t heat the warehouse, and once summer came, the warehouse would be MUCH cooler than the outside air for several weeks.