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2019.07.01 Soloveda Westgate Village Buildng Air Leakage Test Results.pdf Prepared by: Mike Henry Soloveda LLC Ph: 206-793-0046 Mike@Soloveda.com Prepared for: Anthony Jansen Henbart LLC Ph: 206.290.0958 Anthony@henbart.com WSEC Air Barrier Testing Report Westgate Village | Edmonds WA Test Date: 6.28.2019 Report Date: 7.1.2019 2015 WSEC RESULT: 0.226 CFM/ft2 Westgate Village | WSEC Air Barrier Testing Report P a g e 2 | 8 Executive Summary Soloveda performed whole building air leakage testing at the Westgate Village project in Edmonds WA on 6/28/2019. The test was performed according to ASTM E779-19 and the 2015 Washington State Energy Code (WSEC). Soloveda deployed 5 high capacity fans to induce a series of pressure differentials across the building envelope. 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 0.25 CFM/ft2 at dP = 75 Pa defined in 2015 WSEC Section C402.5.1.2. These values are captured in the following table. Table 1: Essential Compliance Results Summary Parameter Standard Leakage* Allowable Result Leakage per ft2 0.226 CFM/ft2 0.25 CFM/ft2 PASS Total Leakage at 75 Pa 17,862 CFM 19,842 CFM PASS *Leakages 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 E779-19 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 8.130 ft2 compared to a building envelope of 79,370 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 8.081 ft2 and 8.178 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 8.130 ft2. Westgate Village | WSEC Air Barrier Testing Report P a g e 3 | 8 Table 2: Comprehensive Test Results - (Positive and Negative Pressure) With Confidence Intervals Parameter Low Mid. High Limit Test Total Leakage @ 75 Pa 0.224 CFM/ft2 0.225 CFM/ft2 0.227 CFM/ft2 < 0.25 CFM/ft2 PASS Pressure Exponent, n 0.635 0.652 0.669 0.45 < n < 0.85 PASS Leakage Coefficient, C0 999 1,071 1,142 --- --- ELA @ 75 Pa 8.081 ft2 8.130 ft2 8.178 ft2 --- --- ASTM E779-19 Test Procedure ASTM E779-19defines 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 Ideally, a test consists of pressurizing and depressurizing a building with fans at differential pressures from 30 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 E779-19 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. Westgate Village | 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 0.223 CFM/ft2 0.225 CFM/ft2 0.228 CFM/ft2 < 0.25 CFM/ft2 PASS Pressure Exponent, n 0.630 0.660 0.690 0.45 < n < 0.85 PASS Leakage Coefficient, C0 915 1,033 1,165 --- --- ELA @ 75 Pa 8.048 ft2 8.134 ft2 8.221 ft2 --- --- Correlation Coefficient, r2 --- 0.99794 --- > 0.98 PASS Table 4: Depressurization Test Compliance Results - Confidence Intervals Parameter Low Mid. High Limit Test Total Leakage @ 75 Pa 0.224 CFM/ft2 0.225 CFM/ft2 0.226 CFM/ft2 < 0.25 CFM/ft2 PASS Pressure Exponent, n 0.628 0.644 0.659 0.45 < n < 0.85 PASS Leakage Coefficient, C0 1,041 1,109 1,181 --- --- ELA @ 75 Pa 8.081 ft2 8.125 ft2 8.170 ft2 --- --- Correlation Coefficient, r2 --- 0.99941 --- > 0.98 PASS Westgate Village | WSEC Air Barrier Testing Report P a g e 5 | 8 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: Pressurized Airflow Data Target dP (Pa) Corrected dP Measured Airflow (CFM) Leakage (CFM) 75.0 74.4 17,780 17,680 70.0 69.9 17,251 17,153 65.0 64.9 16,535 16,442 60.0 60.2 15,482 15,394 55.0 54.8 14,789 14,706 50.0 49.9 13,793 13,715 45.0 44.8 12,785 12,713 40.0 39.7 11,839 11,772 Table 6: Depressurized Airflow Data Target dP (Pa) Corrected dP Measured Airflow (CFM) Leakage (CFM) -75.0 -75.2 17,917 18,019 -70.0 -70.3 17,018 17,115 -65.0 -65.3 16,276 16,369 -60.0 -60.4 15,503 15,592 -55.0 -55.2 14,718 14,801 -50.0 -50.2 13,727 13,805 -45.0 -45.1 12,840 12,913 -40.0 -40.2 11,952 12,020 Westgate Village | WSEC Air Barrier Testing Report P a g e 6 | 8 Figure 1: Graph of Standard Airflow vs Differential Pressure Table 7: General Building and Environment Measurements Parameter Value Site Elevation 266.0 ft Building Height 57.0 ft Building Envelope Area 79,370 ft2 Building Volume 0.0 ft3 Inside Temperature 68.0 degrees F Outside Temperature 71.0 degrees F Windspeed 3.0 mph Zero-flow Pressure Difference 0.2 Pa Stack Effect Validity PASS Westgate Village | WSEC Air Barrier Testing Report P a g e 7 | 8 Test Equipment and Building Test Preparation Procedures Testing was conducted by deploying 5 high capacity fans Retrotec 3000SR orifice blower door fans throughout the building. Three (3) fans were installed in an exterior door off the garage entrance / main lobby, and an additional Two (2) fans were installed at non-communicating yet adjacent commercial space areas. Below is an outline of the measures taken to ensure only legitimate leakage through the envelope was measured. 1. Ducting - microwaves, dryers, bathroom exhausts, A/C ports, isolated with grill mask and/or foam blocks. 2. Windows and exterior doors placed in closed and locked position. Trickle ventilators shut. 3. Relief damper systems isolated. 4. Grey water pipe exhausts isolated where accessible at roof top. Upon successful installation of the fans, the building was pressurized sampling differential pressure in 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 E779-19 testing performed by Soloveda indicates that the building enclosure air tightness capabilities meet or exceed the formal performance requirements set forth in 2015 WSEC Section C402.5.1.2. 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. Westgate Village | WSEC Air Barrier Testing Report P a g e 8 | 8 Report Glossary 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 t he 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 differ ential 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 E779-19 Standard Method for Determining Air Leakage Rate by Fan Pressurization.