2010 ECCC – Air Sealing

An exert from the 2010 Energy Conservation Construction Code Book.  Its describes the 2 potential ways a building inspector can enforce the current code.   Certinspectors is able to perform the necessary test mentioned and will supply the building department with a findings report.


402.4 Air leakage (Mandatory).


402.4.1 Building thermal envelope. The building thermal envelope shall be durably sealed to limit infiltration. The sealing methods between dissimilar materials shall allow for differential expansion and contraction. The following shall be caulked, gasketed, weatherstripped or otherwise sealed with an air barrier material, suitable film or solid material:
1. All joints, seams and penetrations.
2. Site-built windows, doors and skylights.
3. Openings between window and door assemblies and their respective jambs and framing.
4. Utility penetrations.
5. Dropped ceilings or chases adjacent to the thermal envelope.
6. Knee walls.
7. Walls and ceilings separating a garage from conditioned spaces.
8. Behind tubs and showers on exterior walls.
9. Common walls between dwelling units.
10. Attic access openings.
11. Rim joist junctions.
12. Sill plates and headers. Foam plastic (spray foam insulation) shall be permitted to be spray applied to a sill plate, header, and rim joists without the thermal barrier as specified in the Residential Code of New York State, Section 314.4 subject to all of the following:
a. The maximum thickness of the foam plastic shall be 31/4 inches (83 mm).
b. The density of the foam plastic shall be in the range of 0.5 to 2.0 pounds per cubic foot (8 to 32 kg/m3).
c. The foam plastic shall have a flame spread index of 25 or less and an accompanying smoke developed index of 450 or less when tested in accordance with ASTM E 84.
13. Other sources of infiltration
402.4.2 Air sealing and insulation (Mandatory). Building envelope air tightness and insulation installation shall be demonstrated to comply with one of the following options given by Section 402.4.2.1 or402.4.2.2:TABLE 402.4.2 AIR BARRIER AND INSULATION INSPECTION COMPONENT CRITERIA

Air barrier and thermal barrier Exterior thermal envelope insulation for framed walls is installed in substantial contact and continuous alignment with building envelope air barrier.
Breaks or joints in the air barrier are filled or repaired.
Air-permeable insulation is not used as a sealing material.
Air-permeable insulation is inside of an air barrier.
Ceiling/attic Air barrier in any dropped ceiling/soffit is substantially aligned with insulation and any gaps are sealed.
Attic access (except unvented attic), knee wall door, or drop down stair is sealed.
Walls Corners and headers are insulated.
Junction of foundation and sill plate is sealed.
Windows and doors Space between window/door jambs and framing is sealed.
Rim joists Rim joists are insulated and include an air barrier.
Floors (including above-garage and
cantilevered floors)
Insulation is installed to maintain permanent contact with underside of subfloor decking.
Air barrier is installed at any exposed edge of insulation.
Crawl space walls Insulation is permanently attached to walls.
Exposed earth in unvented crawl spaces is covered with Class I vapor retarder with overlapping joints taped.
Shafts, penetrations Duct shafts, utility penetrations, knee walls and flue shafts opening to exterior or unconditioned space are sealed.
Narrow cavities Batts in narrow cavities are cut to fit, or narrow cavities are filled by sprayed/blown insulation.
Garage separation Air sealing is provided between the garage and conditioned spaces.
Recessed lighting Recessed light fixtures are air tight, IC rated, and sealed to drywall. Exception—fixtures in conditioned space.
Plumbing and wiring Insulation is placed between outside and pipes.
Batt insulation is cut to fit around wiring and plumbing, or sprayed/blown insulation extends behind piping and wiring.
Shower/tub on exterior wall Showers and tubs on exterior walls have insulation and an air barrier separating them from the exterior wall.
Electrical/phone box on exterior walls Air barrier extends behind boxes or air sealed-type boxes are installed.
Common wall Air barrier is installed in common wall between dwelling units.
HVAC register boots HVAC register boots that penetrate building envelope are sealed to subfloor or drywall.
Fireplace Fireplace walls include an air barrier.


402.4.2.1 Testing option. Building envelope tightness and insulation installation shall be considered acceptable when tested air leakage is less than seven air changes per hour (ACH) when tested with a blower door at a pressure of 1.0 psf (50 Pa) as verified using instruments and procedures specified in ASHRAE/ASTM E779. The test shall be conducted by a qualified person, who shall demonstrate competence to the satisfaction of the code enforcement official for the conduct of such tests. For the purpose of this section, ACH50 shall mean air changes per hour of infiltration into a house as measured with a blower door at 50 pascals of pressure, in accordance with ASHRAE/ASTM E779. Testing shall occur after rough in and after installation of penetrations of the building envelope, including penetrations for utilities, plumbing, electrical, ventilation and combustion appliances.During testing:

1. Exterior windows and doors, fireplace and stove doors shall be closed, but not sealed;
2. Dampers shall be closed, but not sealed, including exhaust, intake, makeup air, backdraft and flue dampers;
3. Interior doors shall be open;
4. Exterior openings for continuous ventilation systems and heat recovery ventilators shall be closed and sealed;
5. Heating and cooling system(s) shall be turned off;
6. HVAC ducts shall not be sealed; and
7. Supply and return registers shall not be sealed.Test results shall be provided to the code enforcement official and shall include:

a. Name and place of business of the tester;
b. Address of the building which was tested;
c. Conditioned floor area of dwelling, calculated in accordance with ANSI Z65-1996, except that conditioned floor area shall include areas where the ceiling height is less than 5 feet (1524 mm);
d. Measurement of ACH50; and
e. Certification of accuracy of test results and signature of tester.
402.4.2.2 Visual inspection option. Building envelope tightness and insulation installation shall be considered acceptable when the items listed in Table 402.4.2, applicable to the method of construction, are field verified. Where required by the code enforcement official, an approved party independent from the installer of the insulation shall inspect the air barrier and insulation.
402.4.3 Recessed lighting. Recessed luminaires installed in the building thermal envelope shall be sealed to limit air leakage between conditioned and unconditioned spaces. All recessed luminaires shall be IC-rated and labeled as meeting ASTM E 283 when tested at 1.57 psf (75 Pa) pressure differential with no more than 2.0 cfm (0.944 L/s) of air movement from the conditioned space to the ceiling cavity. All recessed luminaires shall be sealed with a gasket or caulk between the housing and the interior wall or ceiling covering.
402.4.4 Fenestration air leakage. Windows, skylights and sliding glass doors shall have an air infiltration rate of no more than 0.3 cfm per square foot (1.5 L/s/m2), and swinging doors no more than 0.5 cfm per square foot (2.6 L/s/m2), when tested according to NFRC 400 or AAMA/WDMA/CSA 101/I.S.2/A440 by an accredited, independent laboratory and listed and labeled by the manufacturer.Exception: Site-built windows, skylights and doors.