OSUT_1_07_25_00_Building_Air_Barrier_System.pdf

OUST-AR RANGE PROJECTS FY19

SECTION 07 25 00.00 06

BUILDING AIR BARRIER SYSTEM

01/10

PART 1 GENERAL

1.1 CONTRACTOR RESPONSIBILITY

The Contractor is responsible for the construction of an air barrier system that is contiguous and connected across the six surfaces of the building envelope meeting the performance requirements as outlined in this specification.

The Contractor shall perform a building air tightness test and thermography test to demonstrate that the building envelope is properly sealed and insulated. The testing shall be performed in accordance with the procedures outlined in this specification.

1.2 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM INTERNATIONAL (ASTM)

ASTM C 1060 (90; R 2003) Standard Practice for Thermographic Inspection of Insulation Installations in Envelope Cavities of Frame Buildings

ASTM D 4541 (2009) Pull-Off Strength of Coatings Using Portable Adhesion Testers

ASTM E 1186 (2003) Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems

ASTM E 1827 (96; R 2002) Standard Test Methods for Determining Airtightness of Buildings Using an Orifice Blower Door

ASTM E 779 (2003) Standard Test Method for Determining Air Leakage Rate by Fan Pressurization

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION (ISO)

ISO 6781 (1983) Thermal Insulation - Qualitative

Detection of Thermal Irregularities in Building Envelopes - Infrared Method, First Edition

1.3 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. The following shall be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES

SD-03 Product Data

Air Barrier Inspector

The inspector shall have 2 years experience in the installation of air barrier materials and assemblies including the experience in joining and sealing various components, and sealing of penetrations of air barriers. The inspector shall have experience coordinating and instructing subcontractors involved in the installation joining an sealing of air barrier materials and components.

Building Air Tightness Test Technician

The testing technician shall have 2 years experience in air tightness testing using the specified testing standard.

Building Air Tightness Test Procedures; G

The contractor shall submit detailed test procedures indicating the test apparatus, the test methods and procedures, and the analysis methods to be employed for the Building Air Tightness Test. The Building Air Tightness Test Procedures shall be submitted not later than 60 days after Notice to Proceed.

The contractor shall submit detailed test procedures indicating the test apparatus, the test methods and procedures, and the analysis methods to be employed for the Thermography Test. The Thermography Test Procedures shall be submitted not later than 60 days after Notice to Proceed.

Thermographer

The Thermographer shall have a Certification in Infrared Building Science from the Infrared Training Center or from the Building Science Institute. The thermographer shall have 2 years experience in infrared thermography.

SD-06 Test Reports

Test Reports; G

The inspection and testing agency will submit a certified written report, in duplicate, of each inspection, test, or similar service to the Contractor with duplicate copies to the Contracting Officer not later than 10 days after each test.

Report Data: Written reports of each inspectionand test or similar service shall include all the Report items described in ASTM E 1827. Additionally, the report shall also include the following information:

a. Date of Issue

b. Project title and number

c. Name, address, and telephone number of testing agency

d. Dates and locations of samples and tests or inspections

e. Names of individuals making the inspection or test

f. Designation of the Work and test method

g. Identification of product and Specification Section

h. Complete inspection or test data

i. Test results and an interpretation of test results

j. Comments or professional opinion on whether inspected or tested Work complies with Contract Document requirements

k. Name and signature of laboratory inspector

l. Recommendations on retesting

Building Air Tightness Test Reports; G

The Building Air Tightness Test analysis, and report shall be submitted not later than 10 days after the test.

Thermography Test Report; G

The Thermography Test analysis, and report shall be submitted not later than 10 days after the test.

1.4 ADMINISTRATIVE AND PROCEDURAL REQUIREMENTS

This section includes administrative and procedural requirements for accomplishing an airtight building enclosure that controls infiltration or exfiltration of air.

1. The airtight components of the building enclosure and the joints, junctures and transitions between materials, products, and assemblies forming the airtightness of the building enclosure are called "the air barrier system".

2. The Contractor is responsible for the coordination between the trades, the proper scheduling and sequencing of the work, preconstruction meetings, inspections, tests, and related actions including inspection and test reports.

3. The Contractor shall ensure that the intent of constructing the building enclosure with a continuous air barrier system to control air leakage into or out of the conditioned space is achieved. The air barrier system shall have the following characteristics:

a. It must be continuous with all joints sealed.

b. It must be structurally supported to withstand positive and negative air pressures applied to the building enclosure.

c. Connection shall be made between:

1) Foundation and walls

2) Walls and windows

3) Walls and doors

4) Different wall systems

5) Walls and roof

6) Walls and roof over unconditioned space

7) Walls, floors, and roofs across construction, control, and expansion joints.

8) Walls, floors, and roofs to utility, pipe and duct penetrations.

4. It is the Contractor's responsibility to ensure that all penetrations through the air barrier system, and all paths of air infiltration or exfiltration, are sealed airtight.

5. Inspection and testing services are required to verify compliance with requirements specified or indicated.

1.5 BUILDING AIR TIGHTNESS TEST TECHNICIAN RESPONSIBILITIES

The technician shall:

a. Describe the test procedures, test apparatus, and analysis method.

b. Perform the Building Air Tightness Test.

c. Perform the Thermography Test.

d. Participate in identifying deficiencies in the building construction upon failure of a test to meet the specified leakage rate.

e. Submit a report of each air tightness test whether successful or not.

e. Submit a report of each thermography test identifying problem areas.

1.6 QUALITY CONTROL

The Contractor shall engage the services of an experienced air barrier inspector to oversee the sequencing and installation of the air barrier component materials and assemblies, to oversee the proper joining and sealing of the materials and assemblies, to oversee the sealing of penetrations of the air barrier materials and assemblies, and to instruct the subcontractors on the above.

1.6.1 Documentation and Reporting

Installers shall document the entire installation process on daily job site reports. These reports include information on the Installer, substrates, substrate preparation, products used, ambient and substrate temperature, the location of the air barrier installation, the results of the quality control procedures, and testing results.

1.7 CONTRACTOR RESPONSIBILITIES

1.7.1 Coordination of Sub-Contractor(s)

The Contractor shall provide coordination between the Sub-Contractors involved in the construction of the air barrier system, coordinate the sequence of construction to ensure continuity of the air barrier system joints, junctures, penetrations, and transitions between materials and assemblies of materials and products from substructure to walls to roof.

The Contractor shall provide quality assurance procedures, testing and verification as specified. The Contractor shall facilitate inspections, tests, and other quality control services specified elsewhere in the Contract Documents and required by the Contracting Officer.

1.7.2 Pre-Construction Conferences

The Contractor shall organize pre-construction conferences between the sub-contractors involved in the construction of or penetration of the air barrier system and the air barrier inspector to discuss where each sub-contractor begins and ends, the sequence of installation, and each sub-contractor's responsibility to ensure airtight joints, junctures, penetrations and transitions between materials, products, and assemblies of products specified in the different sections to be installed by the different sub-contractors.

1.7.3 Construction Mock-Up

The Contractor shall build a construction mock-up of every joint, juncture, and transition between materials, products, and assemblies of products specified in the different sections to be installed. Work will not begin until the mock-up is satisfactory to the Contracting Officer.

1.8 AIR BARRIER SYSTEM PERFORMANCE REQUIREMENTS

The air leakage of the entire building shall meet the air requirements as specified in paragraph BUILDING AIR TIGHTNESS TEST.

PART 2 PRODUCTS (NOT APPLICABLE)

PART 3 EXECUTION

3.1 REPAIR AND PROTECTION

Repair and protection is the Contractor's responsibility, regardless of the assignment of responsibility for inspection, testing, or sample taking and similar services. Upon completion of inspection, testing, or sample taking and similar services, the Contractor shall repair damaged construction and restore substrates and finishes, protect construction exposed by or for quality control service activities, and protect repaired construction.

3.2 TESTING AND INSPECTION

The following qualitative and quantitative tests and inspections shall be conducted by the Contractor in the presence of the Contracting Officer during installation of the air barrier system.

1. Qualitative Testing and Inspection:

a. Provide a Daily Report of Observations with a copy to the Contracting Officer.

b. Ensure continuity of the air barrier system throughout the building enclosure and that all gaps are covered, the covering is structurally sound, and all penetrations are sealed allowing for no infiltration or exfiltration through the air barrier system.

c. Ensure structural support of the air barrier system to withstand design air pressures.

d. Ensure masonry and concrete surfaces are smooth, clean, and free of cavities, protrusions and mortar droppings, with mortar joints struck flush or as required by the manufacturer of the air barrier material.

e. Ensure site conditions for application temperature, and dryness of substrates are within guidelines.

f. Ensure substrate surfaces are properly primed.

g. Ensure laps in materials are at least a 2-inch minimum, shingled in the correct direction or mastic applied on exposed edges with no fishmouths.

h. Ensure that mastic is applied on cut edges.

i. Ensure that a roller has been used to enhance adhesion.

j. Measure application thickness of liquid applied materials to manufacturer's specifications for the specific substrate.

k. Ensure that the correct materials are installed for compatibility.

l. Ensure proper transitions for change in direction and structural support at gaps.

m. Ensure proper connection between assemblies (membrane and sealants) for cleaning, preparation and priming of surfaces, structural support, integrity and continuity of seal.

2. Quantitative Tests:

a. Provide written test reports of all tests performed with a copy to the Contracting Officer.

b. Determine the bond strength of coatings to substrate in accordance with ASTM D 4541.

3.3 BUILDING AIR TIGHTNESS TEST

A building air test shall follow the guidance in the U.S. Army Corps of Engineers Air Leakage Test Protocol for Measuring Air Leakage in Buildings. This protocol is available on the Whole Building Design Guide website- http://www.wbdg.org/references/pa_dod_energy.php. The fan pressurization test to determine final compliance with the airtightness requirement shall be conducted when all components of the air barrier system have been installed and inspected, and have passed any intermediate testing procedures as detailed in the construction drawings and specifications. The test may be conducted before finishes that are not part of the air barrier system have been installed. For example, if suspended ceiling tile, interior gypsum board, or cladding systems are not part of the air barrier system, the test may be conducted before they are installed.

3.3.1 Test Requirements

The air leakage test must be performed in accordance with ASTM E 779 with the following additions and exceptions:

The test consists of measuring the flow rates required to establish a minimum of 12 positive and 12 negative building pressures. The lowest test pressure shall be 25 Pa; the highest test pressure shall be 75 Pa; and there must be at least 25 Pa difference between the lowest and highest test pressures.

The test pressure must be measured in a representative location such that pressures in the extremities of the enclosure can be shown to not exceed 10% of the measured test pressure. At least 12 bias pressure readings must be taken across the envelope and averaged over at least 20 seconds each before and after the flow rate measurements. None of the bias pressure readings must exceed 30 percent of the minimum test pressure when testing in both directions.

Where it can be shown that it is impossible to test in both directions, then the building may be tested in the positive direction only, provided the bias pressure does not exceed 10% of the minimum test pressure.

The mean value of the air leakage flow rate calculated from measured data at 0.3 in wg (75 Pa) must not exceed 0.25 cu ft/ minute per square foot of envelope area (0.25 CFM 75/ft2) and the upper confidence limit as defined by ASTM E 779 must not exceed (0.27 CFM 75/ft2) or the upper confidence limit must not exceed (0.25 CFM 75/ft2). Measurements must be referenced at standard conditions of 14.696 psi (101.325 KPa) and 68F (20C). The envelope area is to be supplied and/or confirmed by the Designer of Record (DOR).

The test shall be conducted with ventilation fans and exhaust fans turned off and the outdoor air inlets and exhaust outlets sealed (by dampers or masking). The contractor must provide a responsible HVAC technician with the authority to place the HVAC system in the correct mode for the pressure test. The test technician must have unhindered access to mechanical rooms, air handlers, exhaust fans, and outdoor air and exhaust dampers.

The contractor must ensure that all windows in the enclosure are kept closed. Entry and exit through doors in the test enclosure must be prohibited during the test. Data collected while the pressures and flows are affected by a door opening and closing shall be discarded.

The testing agency is required to perform a diagnostic evaluation in accordance with ASTM E 1186, whether the building achieves the air tightness requirement or not. The diagnostic evaluation will assist the contractor and responsible parties in identifying and eliminating air leakage so the building meets the requirement upon retesting. The testing results will also be expressed in terms of the Equivalent Leakage Area (EqLA) at 75 Pa. The EqLA is a the equivalent area of a flat plate that leaks the same amount as the building envelope at 75 Pa.

3.4 THERMOGRAPHY TEST

The building envelope shall be tested using Infrared Thermography technology. The thermography testing shall be completed in accordance with the requirements of ASTM C 1060 and ISO 6781. The Contracting Officer shall witness the testing. Testing shall occur just before the building air tightness test. Testing shall also occur during the air tightness test so that areas of building air leaks are detected. If the building air tightess test is failed, Thermographic testing shall be repeated just before and during subsequent air tightness tests until the air tightness test is successful. The contractor shall provide a report. The report shall include thermographs in color and a color temperature scale to define the temperature indicated by the various colors. The report shall identify the high temperature reading, the outdoor air temperature, the building indoor air temperature, and the wind speed and direction. The report shall note any areas of compromise in the building envelope, and shall note all actions required and taken to correct those areas. Final thermography test report shall demonstrate the problem areas have been corrected.

The complete test and analysis will be submitted to the Government for review and approval.

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