Retrotec USACE - Manual (Page 301)

Appendix F F7
F.8 Specifi er and Witness Guidance
F.8.1 Application and Scope
Use this Guide to gain a general understanding of the air leakage test, how it
should be specifi ed, and how to monitor whether the air leakage test has been
properly performed. This air leakage test specifi cation and the required pass/
fail result must be applied to the entire exterior enclosure area as a single entity.
See the included glossary (p. 29) for defi nitions. In many circumstances, it is
useful (but not currently required) to isolate components such as individual
walls or fl oors to diagnose more closely the source of air leakage. In the future,
individual components such as horizontal fl oor slabs may have their own more
stringent requirements, but for now, only the air leakage of the entire exterior
envelope is measured.
The architect or design engineer is responsible for defi ning the bounds of
the enclosure and for calculating its surface area to be used in the results cal-
culation. The surface area will include the fl oor, walls/fenestrations, and roof/
ceiling. This enclosure is often the “exterior envelope” of the building, but
does not always include all exterior walls. Of interest is the functional “air bar-
rier” for the enclosure under test, which may not be the exterior envelope. For
example, heating, ventilating, and air-conditioning (HVAC) rooms with large
louvers open to outdoors, laundry rooms with dampers opening to outdoors,
and loading docks with overhead coiling may be outside the air barrier en-
closure if the design dictates such. This would force their interior walls to be
insulated and air sealed to the same standard as other parts of the enclosure
that face the outdoors.
The boundary of the air barrier must be clearly defi ned in the project draw-
ings. Once properly considered by the design professional, the calculated sur-
face area of the air barrier should be indicated on the design drawings.
For buildings where doorways from each apartment, offi ce, meeting room,
or other area that open from a common hallway or zone and not at the air bar-
rier boundary, the entire building air barrier system must be tested as a whole.
For buildings where doorways of each apartment/offi ce/room lead to the
outdoors (i.e., where there is no direct interior connection between all the
rooms), each apartment/offi ce/room must be tested individually. Walls abutting
adjacent apartments are to be treated as part of the envelope in spite of the fact
that an argument can be made that leakage of the adjacent walls would be to
another conditioned apartment and could therefore be ignored. To allow for
effi cient testing, common walls will be treated as part of the total envelope for
the apartment and each apartment must pass the criteria. In multi-unit apart-
ments, each style of apartment must be tested, including all corner rooms, and
at least 20 percent of all other apartments must be tested.
Buildings over 500,000 sq ft. (46,450 m 2 ) of envelope area may require
special test techniques not covered in this protocol. The building may have
to be broken up into zones separated using boundary pressure neutralization