If there’s one thing I learned from spending last winter in a portable building, it’s that sealing the gaps are of vital importance.
This photo is above the stud wall, where roof meets the wall:
When I tell you that cold air pours through those gaps, it is an understatement.
The “cabin” we were in on the ranch had ample insulation in the walls, but this are had not been sealed & the ceiling not yet insulated. When I would place my hand on top of that stud wall header, it felt like a constant draft of icy air, in cold weather. When we put skirting on building, it helped the intensity of the airflow, but there was still definite cold transfer occurring.
So, we are beginning our build process by sealing all of those gaps with expanding foam insulation. The gaps around the windows are being sealed, as well, even though they will be covered with wall board & trim, as this will help reduce drafts.
I will say that several people told me that I was overreacting by insisting on filling & sealing all of these spaces. However, this photo illustrates the need for it even better than I can explain in words.
That is the expanding foam insulation that has leaked through to the outside. Not to worry, it will be easily trimmed away but it is important to realize that air (& pests, for that matter) was easily able to travel directly in & out of the building through those gaps.