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Duct blower test

Mr. Inspector

SAWHORSE
Joined
Nov 28, 2009
Messages
4,695
Location
Poconos/eastern PA
I was just wondering if anyone requires a duct blower test on a new A. C. only system that will be in the unconditioned attic in an existing house?

Also how can we inspect anything in unconditioned space if the first thing in chapter 11 says:

2009 IRC N1101.1 Scope.
This chapter regulates the energy efficiency for the design and construction of buildings regulated by this code.
Exception: Portions of the building envelope that do not enclose conditioned space .
 
Devils advocate, since it is most likely providing the conditioned air to the conditioned space? Regardless that the equipment/ducts ore outside of the space? Would then the 2009 IECC still kick in?
 
2009 IRC N1101.2 Compliance.
Compliance shall be demonstrated by either meeting the requirements of the International Energy Conservation Code or meeting the requirements of this chapter. Climate zones from Figure N1101.2 or Table N1101.2 shall be used in determining the applicable requirements from this chapter.

The designer can use IRC Chapter 11 or the IECC but not both. The IECC does not seem to have this exception. Probably because it has stuff on outside lighting.

So if they are designing to the IRC we do not look at anything outside of the conditioned space or do we need to refer to the IECC if there is equipment outside of the conditioned space?
 
The equipment is not "part" of the envelope. It is installed inside the envelope, outside of conditioned space. Just like a condenser (sort of)...
 
Is it permitted to be installed in an unconditioned space? our code would not permit it in an unconditioned area.
 
It has a direct connection with the conditioned space, and penetrates the building envelope.
 
Is it permitted to be installed in an unconditioned space? our code would not permit it in an unconditioned area.
Where are you that the code doesn't permit the installation of HVAC equipment in an unconditioned space? What code/cycle are you under and what type of local amendments have you added? I've never seen a place that wouldn't allow the installation of HVAC equipment in an unconditioned space. I see them installed in attics, basements, crawlspaces, etc. just about everyplace but a conditions space.
 
Canada code....Way smarter than ours...

A lot of folks used outdoor wood boilers for a long time in Canada. While standing by their outside boiler with 2 feet of snow on the ground in shorts and a tshirt, some of those old country boys figured out that it's probably not a great idea to have your space conditioning equipment outside of the building.

You can still use outdoor wood boilers under the energy code, provided it meets the minimum efficiency...good luck finding one. Other than that, you are permitted to put the outside unit of the heat pump outside.
 
Where are you that the code doesn't permit the installation of HVAC equipment in an unconditioned space? What code/cycle are you under and what type of local amendments have you added? I've never seen a place that wouldn't allow the installation of HVAC equipment in an unconditioned space. I see them installed in attics, basements, crawlspaces, etc. just about everyplace but a conditions space.

2010 National Building Code of Canada. 9.36.3.5
 
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