Insulation questions
We have just completed a new 100-bed nursing home and we are finding air infiltration where there are penetrations (thermostats, electrical junction boxes) of the interior “T Walls” that separate the resident rooms. The exterior of the building was completed as light frame construction using dimensional lumber. The interior walls are metal framed.
We removed some of the drywall and found that the air/vapor barrier on the exterior wall stops at the T wall where it is glued to the edge of the first metal stud of the wall separating two resident rooms. There is no insulation in this void and the holes in the metal studs are poorly filled with a spray foam.
Is there a IBC or best practice when it come to insulating that void? It seems to me the barrier should have been a continuous sheet covering the entire exterior wall then the interior T walls should have been added. It seems that they insulated and installed the barrier after framing the entire building.
Thanks in advance for any help!
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Replies
Jake,
1. Where are you located? What is your climate zone?
2. What do you mean by "the air/vapor barrier on the exterior wall"? Do you mean a layer of polyethylene installed on the interior side of the studs?
3. Are you the contractor or the owner?
4. Did the building plans include air barrier details?
5. Does the builder understand airtight construction details?
6. Did the builder perform a blower-door test?
1) The climate zone is 6A
2) Yes..The layer of polyethylene installed on the interior side of the studs
3) Owner
4) I'm still researching the specs
5) No!
6) No
Thanks
Jake,
It's hard to make an effective air barrier with polyethylene. It certainly can't be done if you try to "glue" the poly to a steel stud.
No one in the U.S. has used polyethylene as an air barrier for at least 15 years. These days, most builders use taped plywood or OSB sheathing or interior drywall as an air barrier.