I found this very interesting - I always try and crack a window for a couple of hours everyday.
Have you ever realized why you wake up with a headache in the morning? Most the time it will be from your airflow during the night. Last winter we had diesel heating for our home which cost $450 each time we filled the tank minimum - anyhow not being very good with our budget we had about a week in February without diesel heat - we did have a great fire and electric heaters. But during the night it would get very cool and during this time I would wake up so fresh and clear minded to take on the day that I really loved it. Now we have electric heat system and we don't have it turned down to 64 at night and bedroom doors wide open we feel tried and have a stuff head in the morning. I would love to turn the temp down to 50 during the night and stock up on woolen blankets and hot water bottles (like my childhood). Only problem as it would cost to much to get the heat back up the next day - would be good to test and see if it does effect the energy bill?? Love you comments!!!
Breathe Easier - Tips for Better Indoor Air Quality in Winter