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2018.10.04 Soloveda GRE Building 10 Air Barrier Test Report.pdf 10/3/2018 Prepared by: Mike Henry Soloveda LLC M: 206.793.0046 Mike@Soloveda.com Prepared for: Kirk Swenson GOODMAN REAL ESTATE M: 206.619.4631 kswenson@goodmanre.com Building 10 50 Pine Street, Edmonds WA WSEC Air Barrier Testing Report Building 10 | Edmonds, WA Date Tested: 10.03.2018 Report Date: 10.04.2018 2015 WSEC RESULT 0.226 CFM/ft2 Building 10 | WSEC Air Barrier Testing Report P a g e 2 | 8 Executive Summary Soloveda performed air barrier testing at the GRE Building 10 project in Edmonds, WA on 10/3/2018. The test was performed according to ASTM E779-10 and the 2015 Washington State Energy Code (WSEC). Soloveda deployed nine high capacity fans to induce a series of pressure differentials across the building envelope which ranged from 40 Pa to 75 Pa. Once each target pressure stabilized, airflow from each fan was measured and averaged over a minimum of ten seconds. The averaged airflows across all fans were then added together to obtain a single aggregated airflow. The relationship between airflow and differential pressure (dP) was analyzed to estimate the envelope's leakage value and then compared to the allowable limit of 0.4 CFM/ft2 at dP = 75 Pa defined in WSEC Section C402.5.1.2. These values are captured in the following table. Table 1: Essential Compliance Results Summary Parameter Measured Leakage Allowable Result Leakage per ft2 0.226 CFM/ft2 0.4 CFM/ft2 PASS Total Leakage at 75 Pa 24,567 CFM 43,467 CFM PASS *Fan airflows are adjusted to standard references such that results are comparable to other buildings with different test conditions. Stack effect, correlation coefficients, and pressure exponents: Based upon ASTM E779-10 and the 2015 WSEC requirements, the test procedure was valid relative to stack effect, correlation coefficients, and pressure exponents. These are described in the following tables and figures. Equivalent leakage area (ELA): ELA is equivalent to all unintentional leaks of the building envelope combined into a single square-shaped hole given a pressure difference of 75 Pa. While the ELA has no defined limit, it is made available for an alternative interpretation of the results. This building's ELA at 75 Pa is estimated as 11.079 ft2 compared to a building envelope of 108,668 ft2. Confidence intervals: To capture statistical uncertainty, each estimated value has a lower-bound and an upper- bound called a confidence interval. For example, the equivalent leakage area has a 95% confidence interval between 10.976 ft2 and 11.182 ft2. If we repeated this test 100 times under varying conditions, approximately 95 of the tests should have confidence intervals capturing the real value which we report as 11.079 ft2. When determining air leakage compliance, WSEC Section C402.5.1.2 requires us to compare the leakage confidence interval's upper-bound to the allowable limit. The following table is a more detailed summary of test results including Low and High bounds of that value's 95% confidence interval in addition to the average (Mid.) value. See the Test Procedure section for more detail about the Leakage Coefficient and Pressure Exponent. Building 10 | WSEC Air Barrier Testing Report P a g e 3 | 8 Table 2: Comprehensive Test Results Matrix - With Confidence Intervals Parameter Low Mid. High Limit Test Total Leakage @ 75 Pa 0.222 CFM/ft2 0.224 CFM/ft2 0.226 CFM/ft2 < 0.4 CFM/ft2 PASS Pressure Exponent, n 0.578 0.603 0.627 0.45 < n < 0.85 PASS Leakage Coefficient, C0 1,619 1,828 2,037 --- --- ELA @ 75 Pa 10.976 ft2 11.079 ft2 11.182 ft2 --- --- ASTM E779-10 Test Procedure ASTM E779-10 defines a power-law model relating differential pressure across a building envelope (dP) induced by fans with the corresponding airflow (Q) through an orifice with a leakage coefficient C and pressure exponent n: Q = C (dP)n A test consists of pressurizing and possibly depressurizing a building with fans at differential pressures from 40 Pa to 75 Pa. Zero-airflow measurements before and after the test adjust measured dP to correct for any bias pressures detected (Wind, stack effect, etc). Pressurization airflow measurements Q are converted to volumetric standard airflows Q0 of the inside air by correcting for temperature and barometric pressure. Likewise, depressurization test measurements are corrected for outside air temperature and pressure. Measured pressure differences are averaged, and airflows for fans running simultaneously are summed. An unweighted regression estimates the model parameters C and n based on converted volumetric airflows Q0. The leakage coefficient C is "corrected" and renamed to C0 to adjust for standard reference conditions: sea-level pressure and a 68 degrees Fahrenheit temperature. The pressure exponent n is a measure of air turbulence, and must fall within a small limit to ensure model validity according to regulations. The regression's correlation coefficient r2 must be sufficiently close to 1.0 to indicate a proper agreement between the measured data and the power-law model: Q0 = C0 (dP)n Standard volumetric airflow estimates Q0 can now be computed for any given dP and compared to other building sites given the leakage coefficient correction C0. Soloveda follows the E779-10 guidelines both for computing small sample-size confidence intervals using the T- distribution, and for combining parameters and their confidence intervals from pressurization and depressurization data. Building 10 | WSEC Air Barrier Testing Report P a g e 4 | 8 Individual Test Compliance Results The following tables list the separate pressurization and depressurization statistical parameters and compliance results with their confidence intervals used to compute values in Table 2. Table 3: Pressurization Test Compliance Results - Confidence Intervals Parameter Low Mid. High Limit Test Total Leakage @ 75 Pa 0.233 CFM/ft2 0.237 CFM/ft2 0.241 CFM/ft2 < 0.4 CFM/ft2 PASS Pressure Exponent, n 0.529 0.576 0.622 0.45 < n < 0.85 PASS Correlation Coefficient, r2 --- 0.99350 --- > 0.98 PASS Leakage Coefficient, C0 1,773 2,139 2,581 --- --- ELA @ 75 Pa 11.510 ft2 11.703 ft2 11.899 ft2 --- --- Table 4: Depressurization Test Compliance Results - Confidence Intervals Parameter Low Mid. High Limit Test Total Leakage @ 75 Pa 0.210 CFM/ft2 0.211 CFM/ft2 0.213 CFM/ft2 < 0.4 CFM/ft2 PASS Pressure Exponent, n 0.612 0.629 0.647 0.45 < n < 0.85 PASS Correlation Coefficient, r2 --- 0.99921 --- > 0.98 PASS Leakage Coefficient, C0 1,413 1,517 1,630 --- --- ELA @ 75 Pa 10.390 ft2 10.455 ft2 10.521 ft2 --- --- Building 10 | WSEC Air Barrier Testing Report P a g e 5 | 8 Pressurization Test Data The following sections list the model's corrected data inputs for pressurization and depressurization tests alongside figures plotting power-law model trendlines along with corrected data (see Test Procedure Section). Table 5: Measured Pressurized Airflow Data Target dP (Pa) Corrected dP (Pa) Standard Airflow (CFM) 40.0 39.6 17,718 45.0 44.8 18,985 50.0 49.7 20,382 55.0 54.6 21,729 60.0 59.7 22,964 65.0 64.7 23,606 70.0 69.7 24,639 75.0 74.8 25,396 Figure 1: Graph of Induced Airflow vs. Pressurization Difference Building 10 | WSEC Air Barrier Testing Report P a g e 6 | 8 Depressurization Test Data Table 6: Measured Depressurized Airflow Data Target dP (Pa) Corrected dP (Pa) Standard Airflow (CFM) -40.0 -39.9 15,371 -45.0 -44.8 16,635 -50.0 -49.8 17,713 -55.0 -54.7 18,855 -60.0 -59.9 19,827 -65.0 -64.9 20,790 -70.0 -70.2 22,010 -75.0 -74.9 22,994 Figure 2: Graph of Induced Airflow vs. Depressurization Difference Building 10 | WSEC Air Barrier Testing Report P a g e 7 | 8 Test Equipment and Building Test Preparation Procedures Testing was conducted by deploying nine high capacity fans Retrotec 3000SR orifice blower door fans, installed in an exterior man door off the main entrance lobby. Below is an outline of the measures taken to ensure only legitimate leakage through the envelope was measured. Envelope penetrations from units were isolated using 4-inch polyurethane foam blocks within the exterior FAVs. HVAC dampers were placed in the closed position. Internal access hatches were sealed with plastic masking sheets. Gray water lines were sealed at the roof with plastic masking sheets. All doors and windows within the envelope plane were closed. Relief dampers were placed in the closed position. Upon successful installation of the fans, the building was pressurized from 40 Pa to 75 Pa using 5 Pa increments. Before and after each test, zero-flow baseline pressures were taken and used to correct the final pressure measurements. The resulting pressure and flow data points were then plotted to determine their correlation and identify the pressure exponent and leakage coefficient which are indicative of the building's leakage characteristics. Report Conclusion ASTM E779-10 testing performed by Soloveda indicates that the building enclosure zone's air tightness capabilities meets or exceeds the formal performance requirements set forth in WSEC Section C402.5.1.2 of the 2015 WSEC. Congratulations on a successful test. Regards, President Soloveda LLC 206.793.0046 Mike@Soloveda.com This report was prepared for Soloveda's client and contains findings, comments, and observations made by a qualified representative of Soloveda. The report is intended to serve as a Quality Assurance tool, and is provided in a timely manner so that remedial action can be undertaken as necessary. Note that the testing conducted was not inclusive of all specimens present and is therefore limited in nature. Accordingly, Soloveda's statements contained herein do not constitute approval, disapproval, certification, acceptance of performance of products materials, or endorsement by this laboratory/ testing agency. The report is the exclusive property of our client, and relates solely to the specimens tested. Building 10 | WSEC Air Barrier Testing Report P a g e 8 | 8 Report Appendix and Glossary Table 7: General Building and Environment Measurements Parameter Value Elevation 133 ft Building Height 64 ft Building Envelope Area 108,668 ft2 Inside Temperature 68.0 degrees F Outside Temperature 56.0 degrees F Windspeed 3.0 mph Zero-flow Pressure Difference 0.10 Pa Stack Effect Validity PASS air-leakage*, n - the movement/flow of air through the building envelope, which is driven by either or both positive (infiltration) and negative (exfiltration) pressure differences across the envelope. air-leakage rate*, n - the volume of air movement/unit time across the building envelope including airflow through joints, cracks, and porous surfaces, or a combination thereof driven by mechanical pressurization and depressurization, natural wind pressures, or air temperature differentials between the building interior and the outdoors, or a combination thereof. building envelope*, n - the boundary or barrier separating different environmental conditions within a building and from the outside environment. effective leakage area*, n - the area of a hole, with a discharge coefficient of 1.0, which, with a 75 Pa pressure difference, leaks the same as the building, also known as the sum of the unintentional openings in the structure. flow coefficient, n - the constant parameter of the power law equation that relates flow to differential pressure across a building envelope. It represents the theoretical flow rate that exists at a differential pressure of 1 Pa. pressure exponent, n - the exponent applied to the pressure parameter of the power law equation that relates flow to differential pressure across a building envelope. The exponent is a value between 0 and 1 that is indicative of how turbulent the air flow is. A value of 1 represents totally laminar flow. * Definition as given in ASTM E779-10 Standard Method for Determining Air Leakage Rate by Fan Pressurization.