Just wondering but wouldn’t that be dangerous sleeping inside that because of smoke inhalation. The opening to the igloo doesn’t seem like it would be effective at ventilation.
Disclaimer: I am NOT an igloo or survival expert and someone with more experience should be consulted before building an igloo with intent to use it for shelter.
That being said, from what little research I have done, there are multiple ways to vent an igloo, and they have their pros and cons, however sufficient ventilation is very achievable so long as the hole(s) is(are) big enough.
One common option is to vent a hole right in the center at the top. Air current actually keeps snow from blocking up your hole even as snow piles onto the igloo (I understand this has been witnessed with snow accumulation of up to a foot) From what I have read, your door drifting closed is actually a much bigger issue than your vent drifting closed.
TLDR: Vents seem to work fine.
I am assuming this are degrees Fahrenheit. 60° is definitely a little chilly, however it's not actually that cold when the relative outside temperature is so cold. 60° F is about 15.56° C. It's the sort of temperature where you buddle up if it's that cold in September (northern hemisphere) but stop wearing your jacket when it's that warm in March.
That being said, from what little research I have done, there are multiple ways to vent an igloo, and they have their pros and cons, however sufficient ventilation is very achievable so long as the hole(s) is(are) big enough.
One common option is to vent a hole right in the center at the top. Air current actually keeps snow from blocking up your hole even as snow piles onto the igloo (I understand this has been witnessed with snow accumulation of up to a foot) From what I have read, your door drifting closed is actually a much bigger issue than your vent drifting closed.
TLDR: Vents seem to work fine.