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Spray foam insulation in rafters above exisisting blown cellulouse in ceiling

Spray foam insulation within roof rafters is proposed for a large town hall building built in 1883. Location is in Northern part of the mitt in Michigan. Attic space is very, very large. Existing insulation consists of 12" blown in insulation in what I believe to be a non- vented attic space
Heating units and ductwork are in the attic. Plans for the future are to move the furnace to the basement and air condition unit to be in the attic. Considerations are also being discussed for an air exchanger, location not known.
I have search the world over for direction concerning insulation far above existing insulation to no avail. Plenty of info relating to the creation of conditioned and uncondition attic, do's and don'ts associated with initial installation, types of foam, conventional, etc, etc, but nothing for this specific question.

Hope you can help.

Thanks a heap, Steve Miller

Asked by steve miller
Posted Jan 26, 2012 1:07 PM ET
Edited Jan 26, 2012 1:17 PM ET


1 Answer

Select your preferred way to display the comments and click "Save settings" to activate your changes.

So what's your question?

Perhaps it's this one: "Is there any reason that an attic can't have spray foam between the rafters as well as cellulose on the floor?"

If that's your question, the answer is "No, there is you reason you can't do that."

Answered by Martin Holladay, GBA Advisor
Posted Jan 26, 2012 1:51 PM ET

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