< Previous20 Fall 2022 • Ontario Building Envelope Council REFERENCES 1. BC Housing, “BC Housing Design Guidelines and Construction Standards,” 2019. 2. ASHRAE, “ANSI/ASHRAE Standard 62.2: Ventilation and Acceptable Indoor Air Quality in Residential Buildings,” 2019. 3. Energy Star, “EnergyStar Multifamily High Rise Program: Testing and Verification Protocols, Version 1.0, Revision 03,” 2015. 4. International Code Council Inc., “International Energy Conservation Code,” 2021. 5. Passive House Institute US, “PHIUS+ 2018 Passive Building Standard Certification Guidebook - Version 2.0.” Chicago, IL, 2019. 6. U.S. Green Building Council, “LEED v4.1 Residential BD+C Multifamily Homes,” 2019. 7. D. L. Bohac, L. Sweeney, R. Davis, C. Olson, and G. Nelson, “Energy Code Field Studies: Low-Rise Multifamily Air Leakage Testing,” 2020. 8. Air Solutions Inc., “Assessment of Suite Compartmentalization and Depressurization in New High Rise Residential Buildings: Final Report,” Ottawa, ON, 2005. 9. Buchan Lawton Parent Ltd., “Evaluation of Air Leakage Control Measures to Com- partmentalize Newly Constructed Suites in a High-Rise Residential Building,” 2006. 10. S. Klocke, O. Faakye, and S. Puttagunta, “Challenges of Achieving 2012 IECC Air Sealing Requirements in Multifamily Dwellings,” 2014. 11. K. Ueno and J. Lstiburek, “Field Testing of Compartmentalization Methods for Multi- family Construction,” 2015. 12. C. H. Lozinsky and M. F. Touchie, “Suite-level air tightness and compartmentalization in multi-unit residential buildings : How do we achieve our intended goals ?” Build. Environ., vol. 192, p. 107600, 2021. 13. J. Rousseau, “Controlling Stack Pressure In High-Rise Buildings by Compartmenting the Building,” Ottawa, ON, 1996. 14. J. P. Fine, C. H. Lozinsky, and M. F. Touchie, “Reducing Indirect Inter-Suite Air Flow in High-Rise Multi-Unit Residential Buildings: A Parametric Study Using a CONTAM Model,” in ASHRAE Annual Conference, 2022. average air leakage rate. Often, suite bound- aries are made up of multiple assembly types. On average, the suite may appear to have an acceptable air leakage rate; however, broken down by assembly type, the air leak- age rates may vary from tight (e.g., suite-to- suite walls or the building envelope) to loose (e.g., suite-to-corridor walls). This variation is lost in the average, whole-suite metric. Whole-suite air leakage rates also do not tell us anything about the location or size of the air leakage pathways. Numerous studies have found that there is little direct suite-to- suite air transfer via floor / ceiling assemblies or suite-to-suite walls. Most inter-zonal air transfer occurs indirectly via corridors and stairwell / elevator shafts. A large concentra- tion of leakage pathways in the floor / ceiling assemblies will not have as great an impact on inter-zonal air transfer compared to a large concentration of leakage pathways in the suite-to-corridor wall. This lack of specificity in the air leakage metric can lead to in-ser- vice performance gaps. Performance-based standards also do not account for air leakage associated with suite entry doors. In buildings with pressurized corridor ventilation systems, suite entry doors are often installed with large undercuts to facilitate supply of venti- lation air into suites. The prescriptive requirements in Parts 3 and 5 of the NBCC also have their limitations. Air sealing—either for fire separation, acous- tic separation, or air barrier continuity—are often spread across multiple trades and com- pleted at different points in construction. De- pending on the construction sequencing, air sealing activities may be compromised (e.g., access is limited to a specific penetration or interface). In addition, because there is no explicit requirement for air barriers between interior zones, interior air barrier detailing in drawings and technical specifications is often not as comprehensive or explicit as exterior air barrier detailing and may not be exposed to the same level of scrutiny during field reviews. WHAT CAN WE DO? Quantitative tests are helpful in that they give us an indicator that we are moving in the right direction with respect to inter-zonal airtightness, but they should not be used as the definitive benchmark. Ideally, quantita- tive testing and performance-based metrics should be used in conjunction with deliber- ate design of interior air barrier systems and diligent review practices during construction to ensure consistency and quality of interior air sealing. Designers and contractors should consider integrating qualitative testing, such as smoke tracer testing or infrared thermog- raphy, at interim stages of construction. This will aid in quality control and will also help to identify issues while trades are still on site to correct deficiencies. It is also important to recognize that compartmentalization extends beyond the suites. Studies have shown that tightening all interior shafts (stairwell, elevators, and / or garbage chute) can significantly reduce indirect inter-zonal air flow, by limiting stack effect.13,14 Designers could consider airtight doors for stairwell and garbage chute rooms, and elevator vestibules. As our cities densify, and MURBs be- come more common, it is important that we maintain the integrity of our living spaces, not only for our health and safety, but for our comfort as well. Compartmentalization is a key strategy to achieving this goal and maintaining environmental separation within our buildings. n Cara Lozinsky, P.Eng. (BC), is a Ph.D. Candidate at the University of Toronto (De- partment of Civil and Mineral Engineering). Her research focuses on quantifying inter-zonal air leakage in newly constructed MURBs and characterizing its impact on odour / pollutant transfer and building energy efficiency. Prior to starting her PhD, she worked as a building en- velope consultant in Vancouver, BC. Marianne Touchie, Ph.D., P.Eng. (ON), is an Associate Professor at the University of Toronto, jointly appointed in the Departments of Civil and Mineral Engineering, and Me- chanical and Industrial Engineering. She is the director of the Building Energy and Indoor En- vironment (BEIE) Lab, an inter-disciplinary lab that investigates the interaction between building energy use and indoor environmental quality to inform the design of buildings that are both energy efficiency and comfortable and healthy for occupants. FEATURE n n nPushing the Envelope Canada 23 In the last few years, I have been dealing with issues related to building science during the day and mental pathology at night. I could not help but compare the two professions, especially when it comes to forensic work and rehabilitation. In one case the “patient / client” is a human. In the other case, it is a building. Humans can talk, buildings cannot (I bet you knew that). Also, humans can lie about their conditions, whereas buildings cannot. In my opinion, building scientists have it easy compared with mental health practitioners. Signals of misfunction such as mold, rot, decay, and stains, are quite apparent. A thorough investigation would inevitably take us to the root of the problem and provide a hint of the solu- tion, which is not so easy with humans. A structural crack or faulty plumbing could explain leakage, while a misaligned spine does not explain an addiction. And of course, fixing the cracks and the water control layers may stop the leak, but align- ing the bone structure wouldn’t help with binge eating. There is comorbidity in both cases. Buildings may suffer from deterioration of materials, air leakage, and differential pressure at the same time. People may concurrently show symptoms of anxiety, depression, and substance abuse. Distin- guishing causes from consequences is not always a straightforward task. One thing we can state with confidence is that there is no faulty design in humans. Perhaps there are some workmanship issues, but the design is flawless. There is an ongoing debate about genetics versus environmental influence in mental disease. How much influence do inherited traits have on psychological disorders compared with the effect from our surroundings? Research points out at a combination of both factors which vary from one individual to another. Dormant gene predisposition might be triggered by life events. This reciprocal influence is easier to identify in buildings. Hereditary factors such as old masonry and obso- lete mortar pointing practices combined with rain events, may explain spalling of the masonry units. Not every person with genetical predisposition develops Post Stress Traumatic Disorder (PTSD) af- ter a shocking event; some may develop anxiety or phobias, or nothing at all. We don’t know the exact role of genetics and environment on mental illness. Buildings on the other hand, could be assembled with precision, constructed with the best materials and perform well for years, but sudden differential settlement could alter The Building Therapist By Guillermo Cordero, Architectural Representative, Soprema n n n FEATURE24 Fall 2022 • Ontario Building Envelope Council the stability. The same way that a person who seems mentally healthy and balanced for years, may turn into a mess and de- velop substance abuse or extreme fear af- ter witnessing a horrific accident. To construct healthy buildings, we have the guidance of the codes and stan- dards such as OBC, NBC, ASHRAE, ASTM, CSA, and CCMC, among others. These codes and standards tell us in de- tail about procedures and tolerances. For healthy minds, it is well known that we need a balanced diet, stay active, accept who we are, be positive, compassionate, rest, have a supporting network, be grateful, etc. On both sides, there are the trendy, more sus- tainable initiatives. (LEED and keto, green building and green juices, net zero and vegan, GreenGuard Gold and organic farming, mindful ma- terials and meditation, low volatile organic compounds and low calory, Passive House and mindfulness, and many others). But there is no guarantee of success in either case. There are what people in the construction industry call “good practices.” Can we confidently state that if good practices are followed, with buildings and people, they will al- ways be problem-free? Probably not. But it does increase the chances. When we need to assess a building that is displaying signals of pathology, there is a variety of sophisticated tools that yield precise measurements and assist with diagnosis. Consultants can choose from infrared thermography, blower door depressurization, digital hygrometers, heat flux sensors, drones, X-Ray, and many more cool tools. Mental health pro- fessionals have also some instruments at their disposal such as surveys, question- aries, scales, interviews, and screening tools among others. But there is a BIG difference. Properly used building testing equipment provides precise data. Ther- apists must rely on the patient (or client) to provide answers based on what they remember, or how they are feeling at the time of measurement. OK, let’s make up a hybrid profession called Building Therapist. This is a sample conversation between an ill building and the treating scientist: Therapist: Dear 567 Yonge Street (yes, we have to treat them nicely), how do you feel about the effloresce on your south façade? Building: I don’t know where it came from, and it is really annoying me. I feel so ashamed. Therapist: What have you done about it? Building: I have tried all sorts of paint, but the bloody thing keeps re-appearing. Therapist: What could have been the cause? FEATURE n n nPushing the Envelope Canada 25 n n n FEATURE Building: The quality of the masonry! I told my wife (in this story buildings marry) to spend a little more in a less porous brick, but what do I know, right? By the way, this is costing me a fortune; what’s the next step? Therapist: Please fill out the Building Rainscreen Inventory (BRSI) and we will take it from there. Just to give you an idea, here is how one of the 25 questions in the inventory would be. “In average, how often do you feel that you are letting water in?” Se- lect one of the following: 1) All the time, 2) Most of the time, 3) Sometimes, 4) Never. Instead of test cuts and thermal gra- dient readings, we would need to ask the buildings about materials and installation methods used during their construction and hope that they remember and / or tell the truth. We would hear stories about a build- ing retrofitting each single room every six months in an effort to boost self-esteem; the house with flooded basement that de- veloped an intense fear of pumps; the tall tower with acrophobia (fear of heights); the moldy building lying about its insu- lation and blaming the church across the street; or the downtown property with phobia to enclosed spaces. I would love to read “Building Ther- apy for a Cold-Hearted Structure” and compare it with the famous publication by Hutcheon and Handegord. Dr. Lstiburek would beautifully explain the relationship between burst pipes and uncontrolled an- ger. Dr. Straube would tell us how walls with intrusive air flow, end up develop- ing obsessive compulsive condensation (OCC). Professor Ted Kesik already spoke of “building behaviour.” Perhaps I am not too far off. As building scientists, we are very ef- fective when it comes to building assess- ment and restoration; we would never al- low a leak to persist for years. We would go through exhausting research to find out the nature and prevention of build- ing stains. And yet, as humans, we allow unhealthy emotions and actions to go rampant affecting our lives for decades, sometimes forever. Unfortunately, there is no definitive lab test to diagnose mental health problems. Buildings don’t know what is wrong with them. People on the other hand, deep down, know the nature of their emo- tional problems. We just choose to look the other way and leave them untreated, as we would never do with a building. Let’s exert the same rigor and efficiency used to assess building pathology when it comes to evaluating our emotional dilem- mas. Keep the maintenance programs in check, conduct regular inspections, verify work progress, apply the concepts of value engineering to emotional cost, test and re-test, conduct trials of new concepts, change strategies, talk to the experts, do anything until you see progress, and keep working. When it comes to our psycho- logical well-being, every small step goes a long way. There is no extended warranty, but plenty of good practices. n Guillermo Cordero, B. Arch., CTR, BSS, MRAIC, CSP is an internationally trained architect with extensive Canadian credentials in building science and speci- fications. He works as architectural repre- sentative for Soprema in the Toronto area. During the last few years, he has been inter- ested and involved in psychology and psy- chotherapy as a hobby.26 Fall 2022 • Ontario Building Envelope Council The adoption of ambitious building energy use and green-house-gas emission goals has contributed to the increasing popularity of high-performance building standards, such as the Passive House Institute’s (PHI) Passive House Standard and the EnerPHit Standard for retrofits. Al- though we owe much to our European col- leagues for pushing the envelope of high-per- formance building design, it is important to understand that the PHI Standards reference other European standards, the requirements, methods, and theoretical assumptions of which differ from the standards referenced in North American building codes. This article, based on a similar paper pub- lished in CCBST 2022, compares the key fen- estration standards used in North America to those referenced in the PHI standards. In this excerpt, a summary of relevant standards is provided and important similarities and dif- ferences are highlighted to help design and construction professionals understand some of the relevant implications to their work. NORTH AMERICAN STANDARDS In Canada, there are three important standards referenced in the National Build- ing Code of Canada (NBCC) and National Energy Code of Canada for Buildings (NECB) that govern the design and fabrication of most fenestration products: • AAMA/WDMA/CSA 101/I.S.2/A440-17, NAFS - North American Fenestration Standard/Specification for windows, doors and skylights; • CSA A440S1 Canadian Supplement to NAFS; and • CSA A440.2:19 Fenestration energy per- formance. It is worth noting at the outset that differ- ent provincial building codes currently ref- erence different versions of these standards. The research paper focused on the most re- cent versions, NAFS-17 and CSA A440.2:19; however, practitioners should be cautious when referencing this article as the require- ments of their local authority having jurisdic- tion may differ. The NBCC references other standards for the design of certain fenestration prod- ucts, such as AAMA CWM-19 Curtain Wall Manual and AAMA TIR A7 Sloped Glazing Guidelines, but the North American Fen- estration Standards (NAFS) was the focus of the study. NAFS is a performance-based standard that specifies the requirements for FEATURE n n n Fenestration Without Borders: A Comparison of North American and Passive House Fenestration Standards By Brandon Gemme, Project Engineer, RJCPushing the Envelope Canada 27 laboratory testing and defines performance ratings for most fenestration products. There are five primary performance requirements in NAFS: structural strength (against wind, snow, dead loads, etc...), water penetration resistance, air leakage, operating force, and forced-entry resistance. Based on the testing results of the fenestration product in these categories, a “Performance Class” and “Per- formance Grade” are assigned according to NAFS. CSA A440S1, the Canadian supple- ment to NAFS, specifies some additional re- quirements for Canadian fenestration prod- ucts, including different labelling require- ments and different air leakage performance requirements. Interestingly, the only parts of NAFS that overlap with the PHI standards are fenestra- tion performance rating and air leakage re- quirements, whereas CSA A440.2:19 shares much more overlap with the PHI standards. CSA A440.2:19 specifies the methodology for determining many fenestration energy performance properties that are also require- ments of the PHI standards, including overall coefficient of heat transfer (U-factor), solar heat gain coefficient (SHGC), visible trans- mittance (VT), Energy Rating (ER), and Temperature Index (I). CSA A440.2 refer- ences several National Fenestration Rating Council (NFRC) standards for the determin- ation of these properties, the most relevant for comparison with the PHI standards being ANSI / NFRC 100 (U-factor) and ANSI / NFRC 200 (SHGC and VT). However, CSA A440.2 does not specify the minimum requirements for these values like the PHI standards does. PHI STANDARDS Several requirements must be met for a building to achieve compliance with the Pas- sive House Standard including requirements for maximum heating demand and / or load, cooling, and dehumidification demand and / or load, airtightness testing, and renewable primary energy (PER). These requirements vary regionally based on the project’s climate zone. The PHI EnerPHit standard for building retrofits has two certification pathways: the energy demand method and the component method. The energy demand method sets similar, although less stringent, whole build- ing heating and cooling demand require- ments as the Passive House Standard. The component method specifies requirements for the main components of the building including opaque components, transparent components, and mechanical equipment. For fenestration, the main performance requirements are maximum heat transfer coefficient (U-factor), solar heat gain co- efficient (g-value), and maximum solar load during cooling period. Regardless of which certification pathway is taken, buildings must meet minimum requirements for airtightness testing and PER. PHI also provides component certifi- cation for products that demonstrate com- pliance with PHI’s climate zone-based performance requirements. Although not mandatory, the use of certified components is generally recommended for projects seek- ing certification under the Passive House or EnerPHit Standard. This is because PHI has previously verified the performance of these components so that they can be easily incorporated into the Passive House Plan- ning Package (PHPP) energy modelling software, without the need for further veri- fication by PHI. As such, my research also considered the requirements for PHI com- ponent certification for transparent building n n n FEATURE Figure 1: Criteria for the component pathway of the EnerPHit Standard.28 Fall 2022 • Ontario Building Envelope Council components and opening elements and the several European standards referenced in those documents. COMPARISON OF STANDARDS Comparisons between the fenestration requirements in North American and PHI standards can be categorized into the follow- ing four categories: 1. Classification and rating of fenestration products; 2. Energy performance requirements; 3. Hygiene criteria and condensation index; and 4. Airtightness requirements. Some differences between the North American and PHI standards impacts the majority of these categories. For example, different standard size requirements for test- ing various types of fenestration products can significantly complicate comparison be- tween the standards; the frame / glass ratio and overall unit size impact many fenestra- tion characteristics including U-factor and airtightness. Another important difference between the standards is the boundary conditions used for modelling energy performance characteristics. Notably, exterior air tem- perature in the NFRC standards is de- fined as -18oC, whereas the PHI Standards specify an outdoor temperature of 0oC. This variation has a significant impact on the modelling results and has interesting implications for the design of fenestration products. Research by Hanam (2014) and RDH (2014) found that the centre-of- glass U-value is optimized under NFRC conditions (T o=-18 o C) with an IGU gap of approximately 14mm, whereas the opti- mal gap size for the PHI cold-temperate climate standard condition (T o=0 o C) is approximately 18mm. This impacts the typical IGU gap sizes that we see used in different parts of the world. Of interest to many practitioners are the variations in U-value determined by the dif- ferent methodologies. Research by RDH (2014) and Hanam et al. (2014) modelling various window frame/glazing combinations using the NFRC and PHI standards found that whole window U-value results varied by roughly +/- 15 per cent based on multiple variables. Notably, in most cases modelled, the NFRC methodology tended to result in higher (worse) U-values than the PHI meth- odology, but the difference in results were reduced when modelling triple glazed fenes- tration systems. Another important difference is the way that heat loss is accounted for through edg- es of the glazing and frame. The PHI stan- dards determine the linear thermal trans- mittance ( Ψ) through the edge of the glass and the frame-to-wall connection, whereas the NFRC standards use an edge of glass U-factor around the line of sight and does not account for heat loss through the frame to wall connection. This means the variables used to account for heat loss through the edges are fundamentally different: edge of glass U-factor is based on an area whereas Ψ is based on a measure of length. In gen- eral, the concept of linear thermal transmit- tance is not referenced in CSA A440.2:19 or NFRC standards. Both standards have measures to esti- mate fenestration potential for condensa- tion. Temperature Factor (f rSI) in the PHI standards and Temperature Index (I) in CSA A440.2:19, although very similar theoreti- cally, differ in that Temperature Factor (f rSI) calculates the coldest temperature on the interior surface of the fenestration product using computer simulation software, where- as Temperature Index (I) determines this through physical testing. Because the physi- cal test places the sensors on the glass 50mm from the sight line, it does not measure the coldest temperature on the frame, affecting the comparability of the measures. IMPLICATIONS Due to the numerous differences be- tween the NAFS and PHI standards, people working on PHI projects in North America must ensure that any products used on their projects meet all applicable requirements of their authorities having jurisdictions. It may be necessary to complete NAFS testing of a PHI certified fenestration component if it is being imported internationally, or it may be necessary to model the energy performance characteristics of the fenestration product ac- cording to CSA A440.2 / NFRC. It is worth remembering that energy performance of fenestration products are determined in accordance with particular standards and that the methodologies and assumptions in these standards impact the results. Because of this, energy perform- ance values determined under one standard should not be directly compared to the same values determined under another standard. One way to clarify this difference is to add subscripts based on the standard used to de- termine the value (i.e. U NFRC, U PHI, etc…). To reduce risk and simplify the design and construction process, the use of PHI certified fenestration products developed in North America is generally recommended for pro- ject seeking compliance with the PHI stan- dards—as these will likely already meet the requirements of the authority having jurisdic- tion and PHI. n Brandon Gemme, P.Eng., BSS, CPHD, is a Project Engineer at RJC’s Building Science and Restoration division in Toronto. He received his Bachelor of Applied Science in Civil Engineer- ing from the University of Toronto in 2017 with a minor in Sustainable Energy Systems. He is responsible for evaluations, investigations, and remediation of building envelope systems as well as the implementation of rehabilitation and preventative maintenance programs. He has been involved in several deep energy retro- fit projects and has gained valuable experience in the design, modelling, and management of these projects. Brandon is passionate about im- proving building performance, with the goal of providing more sustainable, healthier and com- fortable spaces for end users. FEATURE n n n The PHI EnerPHit standard for building retrofits has two certification pathways: the energy demand method and the component method. Pushing the Envelope Canada 29Next >