It's (still) cold in here

Q. As it gets colder, I’m feeling the same draft I felt last winter, even though we renovated our kitchen and dining room and put in central air to get rid of our wall unit. Our crawl space and walls got insulation, and the crawl space above the kitchen got extra-heavy R-38, but I’m still feeling cold. Did we miss something? Can this be fixed?

A. If bracelet bells are a-jingling from shivers and chestnuts are roasting but the room is cold, you’re not alone. Chills can be caused by many factors during construction. When I can, I try to see corrections made before wallboard goes up. The problem’s cause is people making it look like they insulated when all they did was enough to get through the job and get paid.

The insulators don’t want to be blamed by the sheet-rockers for making the walls wavy, so they take the tabs — those paper edges of insulation blankets — and turn them sideways, stapling them to the sides of the wall studs instead of across the room-side face of the studs. Staples on the room face of wall studs upset sheet-rockers, who want to quickly move things along and complain if they have to take an extra 10 minutes per room to tap in the staples sticking part way out before putting up the wall boards. The trouble created by not overlapping the side paper tabs is that the vapor barrier isn’t sealed and cold air gets all the way to the wall board, which has no insulation value. This is often part of a room’s chill problem.

Insulators often stuff the insulation right to outside wood sheathing boards, reducing the necessary air space intended to reduce moisture buildup in the wall cavities, if the carpenters have left a small air gap to the outside for airflow, which I rarely ever see. Crawl space insulation must be installed vapor-barrier-up, with hangers holding insulation from sagging, before sub-floor sheathing is placed, but few do this correctly, either, causing the same problem. I often see insulation installed from underneath, with the vapor barrier facing downward and hanging, which does little to prevent heat loss or moisture damage.