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2 Specifying Building Airtightness Tests Terry Brennan Camroden Associates, Inc.

3 Specifying a Building Airtightness Test Air Barrier Association of America (ABAA) is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-aia members are available on request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

4 Copyright Materials This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. Air Barrier Association 2014

5 Air Barrier Association of America -PRESENTATION CODE OF ETHICS- The Representative, when speaking about Air Barrier technology and using language, information, presentations, logos, or any other communication means that could be reasonably likely to cause the recipient(s) of such information to believe that the communication represents an official ABAA technical viewpoint, shall: Hold themselves out to the public with professionalism and sound ethics by conducting themselves in a way which reflects positively on ABAA and the ABAA members Clearly state their affiliation Identify their relationship with ABAA Declare that they are presenting an official (unmodified) presentation prepared by ABAA Indicate whether the presentation is at the official request of ABAA This is an AIA Accredited Presentation This presentation will not highlight focus or reference to a specific product of manufacturer

6 Learning Objectives 1. Students will be able to select an airtightness target 2. Students will be able to select a test method 3. Students will be able to place test specification in an appropriate division 4. Students will be able to list required information in a test specification

7 Who Here Specifies airtightness tests? Conducts airtightness tests? Specifies hygro-thermal (heat, air and moisture control) systems for building enclosures? Installs hygro-thermal systems in building enclosures? Specifies or conducts building enclosure commissioning?

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9 Commissioning process Covers three phases of building life: Pre-construction: During Construction Operations and maintenance Commissioning activities include: Hire a commissioning agent Owners Project Requirements (OPR) - start where the client s at Florence Hollis Where d that come from? - Basis of Design (BOD) Construction document review Kick off meeting Quality assurance programs Inspections Performance Testing Acceptance requirements Systems manuals Training for building operations

10 The assumed but unstated OPR: People expect their building to work!! And get mad when it doesn t!

11 What s an Airtightness Test? Induced pressure difference 10 Mass flow in Mass flow out

12 Why test? To test for compliance with an airtightness specification or regulation To provide QA on design and workmanship To demonstrate retrofit effectiveness To determine leakage parameters to use in infiltration modeling To find air leaks qualitative test

13 Tests can be applied to: A mock-up demonstrate effectiveness of design or workmanship Specific assemblies in a building enclosure in situ effectiveness of design or workmanship The whole building enclosure with or without HVAC related transitional zone air leakage A sub-sections of the building containment of the vulnerable or the offensive

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15 Tests may be Qualitative E1186

16 Qualitative?

17 80 Repeated Tests at the reference induced pressure difference. E Induced 75 Pascals Shell Delta P (Pascals) Time (seconds)

18 Regression analysis on Transformed Nonlinear Function: (E779) Multipoint regression test E779, USACE Q cfm = C*(ΔP pascals ) n Where C = flow coefficient n = flow exponent (0.5 n 1.0) Airflow (CFM@STP) Pressure Difference (Pascals) This is a simplification. Air density and viscosity also affect flow and the leakage curve really isn t a power law.

19 Modern test equipment has greatly reduced measurement errors.

20 What data is needed? Airflow through test fans Pressure difference across the test enclosure during baseline condition Pressure difference across the test enclosure induced by test fans Temperature of air passing through the test fans (measured by thermometer) The altitude of the building site (from atlas) Test enclosure surface area or building volume depending on test results Interior pressure differences to monitor single zone condition (used to determine whether a test is valid, not used in calculations)

21 Airtightness Units Airflow at a test pressure: CFM at 50 pascals (CFM50) Leakage Area - ELA (4 pa) - EqLA (10 pa) Airflow at a test pressure normalized (divided) by enclosure area or volume CFM at 75 pascals per square foot of enclosure (5 or 6 sides of the box) Air Changes per Hour at 50 Pascals

22 Specifying an Airtightness Test Make it clear who hires the testing agency Do not repeat or contradict items that are adequately covered in the referenced test methods Include a rationale for any specification that contradicts requirements in the referenced test method Do not require that the testing agency verify that all air barriers are installed correctly (ummm, it s covered by brick)

23 Specifying an Airtightness Test The purpose of the test Qualifications of testing agency Conditions that must be met before the building can be tested Contractor, owner responsibilities Test method (E779, E1827, ACE Protocol, RESNET) Airtightness acceptance criteria (CFM/ft2 enc. or ACH50) Test enclosure boundaries Test enclosure surface area or building volume Treatment of HVAC penetrations and overhead doors and dock levelers How the test result is interpreted What happens if the building fails Reporting requirements

24 Qualifications of testing agency? Experience References Price?? Certification??

25 Preconditions for Test All materials, assemblies and systems to form the continuous air barriers systems must be installed including any HVAC equipment, ducts and fittings included in the test boundary No one in building but testing agencies and witnesses. Ideal but often not the case ABAA: the designated test enclosure shall be completed for testing

26 The contractor must provide Enclosure completed to test conditions Power for test fans Person authorized to place HVAC and combustion equipment in test mode Access to all spaces within the test boundaries Safe access to all HVAC and overhead door related penetrations, openings and dampers

27 Airtightness Test Standards ABAA Standard Method for Building Enclosure Air Tightness Compliance Testing - Recently balloted and passed Army Corps of Engineers ASTM E779 - Standard Test Method for Determining Air Leakage Rate by Fan Pressurization ASTM E1827-Standard Test Methods for Determining Airtightness of Buildings Using an Orifice Blower Door RESNET mortgage guide; currently out for public review as ANSI standard ASTM E Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems ASTM E Standard Test Method for Determining Air Leakage of Air Barrier Assemblies ASTM E283, E783 Laboratory and field air leakage testing

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29 What Division? 01 - Building Enclosure airtightness testing E1186, ABAA, ACE, E1827, E QA testing for installed air barrier materials and assemblies (In combination with inspection requirements) ABAA QAP; E window, curtain wall, doors airtightness testing - E283, E damper leakage testing AMCA 500-D

30 Air Tightness, Codes and Programs 2012 IECC requires continuous air barriers and provides three paths to compliance. ASHRAE cfm75/ft2 or enclosure commissioning. GSA requires continuous air barriers and the enclosure is less than 0.4 cfm75/ft2 of enclosure (all 6 sides) P100 Army Corps of Engineers requires continuous air barriers and an ASTM E779 fan pressure test proving that the enclosure is less than 0.25 cfm75/ft2 of enclosure (all 6 sides) International Green Code has adopted it. Passive House requires continuous air barriers and an ASTM E779 fan pressure test proving that the enclosure is less than 0.6 ACH50 (around cfm75/ft2 enclosure (all 6 sides) British Code for museums and archival storage is less than 0.08 cfm75/ft2 of enclosure Energy Star Multifamily Highrise 0.3 cfm50/ft2 enclosure; fan door test required Tightest building I ve tested: commercial 0.05 cfm75/ft2 enclosure; residential 0.28 ACH50 (around 0.01 cfm75/ft2 tested in 1982); Leakiest building I ve ever measured 50 ACH50 (5 cfm75/ft2 )

31 Multifamily Compartmentalization LEED Multifamily ETS PR cfm 50/ft2 unit enclosure (all six sides) Blower door test must be performed A sampling protocol may be used EnergyStar for Highrise 0.3 cfm 50/ft2 unit enclosure Blower door test must be conducted (E or E1827) Sampling protocol spelled out in standard may be used Requires preliminary and final testing

32 Air tightness targets for manufactured assemblies Curtainwall, storefront: 0.06 cfm75/ft2 of curtainwall - Architectural Graphic Standards AAMA Class 1A low leak dampers: 1.36 cfm75/ft2 of damper

33 Clearly identify test zones The number of test enclosures must be identified. A target airtightness for each test enclosures must be specified. Test enclosure may be whole buildings or sub-sections of buildings. Boundaries for each test enclosure must be clearly identified in specifications and drawings. ABAA allows tests that include single zones, multiple zones that are tested simultaneously, multiple zones tested independently and guard zones.

34 Clearly identify test enclosure boundaries

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36 Specify the maximum allowable air flow at reference pressure The surface area (or volume) of each test enclosure must be included in the specifications. Calculate the maximum allowable airflow at the specified reference pressure for each test enclosure. Calculations must be documented in such a way that a third party can follow them.

37 Incorrect enclosure surface area or volume calculations may be responsible for the largest errors in test results.

38 Target = 2,702 cfm75 Tested = 1,217 cfm75 Target = 10,410 cfm75 Tested = 8,109 cfm75 Health Network space Enclosure area = 26,026 ft2 maintain zero pressure difference between the two zones during the test Pharmacy space Enclosure area = 6755 ft2 Two zone simultaneous test

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40 Compartmentalization Fan Test The test is applied to each unit: Doors and windows in each test unit closed but doors and windows in neighboring units open Intentional openings, supply diffusers and exhaust and return grilles temporarily sealed

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43 Specify Building Preparations What is closed and what is masked depends on the purpose of the test. ABAA has two default test preparations for the building: Air barrier systems test (all HVAC penetrations sealed for test) Operation enclosure test (HVAC related penetrations with dampers closed but not masked Tests for different purposes may be specified. The specification must then include a table of penetrations stating: Whether the opening has motorized dampers, gravity dampers or no dampers Whether or not dampers will be closed or open for test Whether or not openings will be temporarily air sealed for the tests

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46 Interpreting results A test can return one of three results: It clearly passes It clearly fails and I can t tell 95% Confidence Intervals ACE and ABAA test protocol specify: PASS: If test result 0.25CFM75/ft2 and 95%CI 8%: If test result 0.25CFM75/ft2 and 95%CI > 8%: PASS: if test result + 95%CI 0.25 CFM75/ft2 FAIL: if test result + 95% CI > 0.25 CFM/ft2 FAIL: If test result >0.25CFM75/ft2 ABAA allows failing a building if the specified airflow produces less than 75% of the reference test pressure

47 What if it fails? Additional air sealing must be conducted until it passes Some other compensation?

48 Report Building Testing Agency Building Description Test Results Identification of test enclosure boundaries. Test configuration of each intentional opening in the building enclosure including: Test environmental conditions Measured test results in tabular form Conclusions

49 A Final Whole Building Airtightness Test Documents compliance or failure to comply with an airtightness specification Provides induced pressure difference to aid in finding remaining air leaks (E1186) Provides motivation to effectively install air barrier assemblies and identify air leakage sites not detailed in drawings and specs during construction Does not otherwise make buildings more airtight