by Andrew Larigakis RIBA Architect AIBC LEED AP CPHD
June 13th, 2018
“COP23 is also about Passive House…The United Nations (UN) explicitly mention Passive Houses as a possibility to increase the energy efficiency of buildings and thus reduce global warming”1
Government institutions are increasingly recognizing the role the Passive House Standard can play in effectively reducing greenhouse gas emissions and are beginning to introduce the standard into their requirements and codes for all types of new buildings.
The City of Vancouver is a leader in North America with aggressive green building goals supported by regulations and policies that include Passive House as a path to compliance. The City of North Vancouver is also moving forward with its own requirements; their most ambitious regulatory regime applies to the new Moodyville neighbourhood where Passive House forms a route for gaining approvals. Pointing in the same direction, though currently with only voluntary standards and a long-term outlook, British Columbia’s new Step Code provides potentially effective Passive House-related standards for greenhouse gas reductions.
While the Passive House Standard has been in existence since the mid 1990s and tens of thousands of buildings meeting the standard have been built worldwide, we are only now beginning to see the Standard and its approach to green building embedded into government requirements and building codes outside of jurisdictions in Northern Europe. Applying the Standard across the board to buildings has the potential for significant impact on CO2 emissions as compared to the current smattering of “green showpiece” projects, many without an energy focus.
City of Vancouver Embraces Passive House Standard
“We’re seeing increasing interest in the Passive House Standard. Projects are coming forward using Passive House as a tool to meet municipal permitting requirements and drive down green house gas emissions.” 2
The City of Vancouver’s goal is to achieve zero emissions in all new buildings by 2030. Interim targets include a 70% reduction in emissions from 2007 levels for new buildings by 2020 and 90% by 2025. 3 The City’s lofty ambition is to “lead the world in green building design and construction.”4 The Passive House Standard is acknowledged and supported by Vancouver as an effective vehicle in working to this goal.
The embrace of the Passive House Standard is most apparent in Vancouver’s requirements for rezoning applications. Projects for rezoning are required to meet green building requirements to be “near zero” or “low emissions” buildings”5. In the paths to compliance, the City specifically references the Passive House Standard as an accepted route to meet these requirements. The City also accepts Passive House using PHPP modelling for energy code compliance for large non-rezoning buildings.
Though not rocket science, meeting the Passive House Standard is not easy and requires changes to the way we think about making buildings in North America. Rather than focus on the mechanical solutions that have so far mostly failed to deliver the kind of emissions reductions promised, the Passive House approach is more oriented to the building envelope. Passive House requires a high level of air tightness, generous insulation and high performance windows. High efficiency heat recovery ventilation is also typically included. Meeting the ambitious, near zero or low emissions requirements of the City of Vancouver rezoning will likely require starting with this kind of Passive House approach whether or not one chooses the Passive House Certification route to compliance.
Table 1 below describes the requirements to meet the Passive House Standard.
Table 1 Passive House Prerequisites
|Space Heat Demand||Maximum 15 kWh/m²a or heating load maximum 10 W/m²|
|Pressurization Test Result||Maximum 0.6 ACH @ 50 Pa (pressurizing and depressurizing)|
|Total Primary Energy Renewable (PER)||Maximum 60 kWh/m²a|
Over recent years the City has made significant efforts to remove regulatory barriers that might have impeded Passive House projects. Vancouver now has several staff members, including two building inspectors, who are trained and certified in Passive House design. For non-single family or duplex projects, zoning regulations have exclusions from area calculations for the additional thickness of insulation typically needed in this kind of building.6
For single family residences, the City has issued separate guidelines for Passive House projects that include numerous zoning relaxations. Recognizing that high energy efficiency typically requires thicker insulation, the additional thickness of wall is excluded from floor area calculations. Similarly, there are relaxations of height requirements, rear yard setbacks and overall building depth for Passive House projects. There are also exclusions for external shading, “roof-mounted energy technologies” and venting skylights.7
Passive House projects have recently taken off in a big way in the region. Leading the charge is Cornerstone Architecture who currently have 15 Passive House projects on the go; most are wood frame, mid-rise multi-storey residential buildings in Metro Vancouver. Recently completed is The Heights project, a six-storey wood frame building in the City of Vancouver with 85 units of rental accommodation and ground floor commercial. Under construction is Spire Landing, also in Vancouver, with four storeys and 95 units. The architects have been able to take advantage of the floor area exemptions in Vancouver’s bylaws for thicker, more heavily insulated walls on these and other projects. They also feel that the City’s enthusiasm for energy efficient and Passive House buildings has been helpful through the approvals process.
Due to its relatively low level of thermal conductivity relative to other construction materials, virtually all, if not all, Passive House buildings in BC to date have been of wood construction though the use of wood is not a requirement of the standard.
Another Vancouver project, this one at 1400 Alberni Street by Robert A.M. Stern Architects in association with Vancouver-based MCM Partnership, takes Passive House to a new scale. The two buildings, one 43 storeys and the other 48, would, for the moment, be the world’s tallest passive house towers. The design is an emphatic move away from Vancouver’s standard and grossly inefficient glass towers with massive thermal bridging through concrete slab extensions to the exterior. As an ambitious Passive House project, the 60,380 m2 (650,000 SF) of building has been received with considerable enthusiasm and support from the City in its early stages of rezoning so far.
Rezoning and Development permit applications for Passive House projects at the City are growing exponentially and Chris Higgins, a Green Building Planner there, says it is “likely Passive House will be used more broadly as a building code compliance and rezoning policy option” in coming years.
Passive House comes to the City of North Vancouver and Moodyville
Playing catch up to Vancouver in reducing GHGs from buildings is the City of North Vancouver. While municipal requirements are rapidly evolving, the City’s overall goals for energy savings are still relatively modest but change is on its way. The 2014 Official Community Plan calls for a 15% reduction in greenhouse gas emissions over 2007 levels by 2020 and a 50% reduction by 2050.8 North Vancouver has recently adopted the new BC Energy Step Code (described below) that has standards based on building type.
Of particular note, is the Moodyville Area of North Vancouver, a primarily single family residential area that has been recently rezoned for higher density housing. Seeing an opportunity for advancing their sustainability ambitions in the redevelopment of this area, the City of North Vancouver is offering a density bonus to projects that achieve Passive House certification.9 One of three conforming routes to high energy efficiency and resultant increased density, North Vancouver is actively promoting Passive House projects with a promise of prioritized treatment in the processing of permits. The strategy is yielding results and the municipality now has a raft of new Passive House projects before it for approval and starting construction.
BC Energy Step Code and the Passive House Standard
In April of 2017, the BC government introduced the multi-tiered BC Energy Step Code10 to attempt to bring a consistent set of standards for energy efficiency to the many jurisdictions in the province. With the introduction of the new code, the Province is stripping individual jurisdictions, with the exception of Vancouver, of the power to set their own energy efficiency standards; in place of this power municipalities have a choice of levels of energy performance from within the Step Code to choose from.
At its highest levels, or “steps”, the new code requirements approach Passive House standards and the overall code approach is now more closely aligned with Passive House principles. For instance, the BC Energy Code effectively prioritizes building envelope performance. Under the new code buildings must be tested for air tightness. More insulation and better windows than is currently typical will be needed to meet all but the lowest level of the code. Also, energy modeling is also now required for all projects as the Step Code is performance based rather than prescriptive.
The Step Code has two sections, one for Part 9 residential buildings that applies province wide and a second for multi-unit residential and commercial that applies only to Climate Zone 4 (the Lower Mainland, southern Vancouver Island, southern Okanagan). In contrast, Passive House requirements are the same across all building types and all climate zones.
For Part 9 buildings the new code has 5 levels or “steps”; for multi-unit residential, 4 levels; and for commercial, 3. To meet Step 5, the highest level for Part 9 buildings, Passive House Certification provides a clear route to compliance. Section 220.127.116.11 3) of the new energy code states “buildings designed and constructed…. to the Passive House Planning Package, version 9 or newer, are deemed to comply”.11 In the provinces guide to the new code, Step 5 is described as “equivalent” to Passive House.11
The requirements for Step 5 are similar to Passive House but not identical. Thermal energy demand is the same for both at < 15 kWh/m2year or Peak thermal load < 10 W/m2.
Air changes per hour in the code are 1.0 whereas the PH is slightly more stringent at 0.6. While the Step Code has a requirement only covering Mechanical Energy Use Intensity with a maximum 25 kWh/m2year, Passive House measures overall Primary Energy Renewable (PER) setting the limit at 60 kWh/m2year (see Table 1).
With multi-unit residential, the steps in the new energy code only go up to 4. In this instance thermal energy demand is again set at < 15 kWh/m2.year – the same as Passive House. While the Step Code sets a maximum total energy use intensity at 100 kWh/m2.year, Passive House has a requirement for Primary Energy Renewable with, as previously noted, a limit of 60 kWh/m2year (see Table 1).
Lastly, for commercial buildings, the Step Code only goes up to Step 3. Here the thermal energy maximum is increased to 20 kWh/m2year and the maximum total energy use intensity goes up to 120 kWh/m2year which matches earlier versions of the Passive House Standard.
Table 2 Comparison – Passive House vs. BC Energy Step Code
|Air changes per Hour
@ 50 Pa
|Primary Energy Renewable
|Mechanical Energy Use
|Equipment and Systems – Maximum Total Energy Use Intensity
|Passive House prerequisite||0.6||< 15
(or Peak thermal load < 10 W/m2)
|Step 5 (Part 9 only)||1.0||< 15
(or Peak thermal load < 10 W/m2).
|Step 4 (Multi-unit residential only)||NA||< 15||NA||NA||100|
|Step 3 (Commercial only)||NA||< 15||NA||NA||120|
The BC Energy Step Code, though different from Passive House, has made a significant move to the methodology and criteria of the Passive House Standard. By explicitly accepting Passive House as an “equivalent”12 of the highest levels of the Step Code for each of the three building types referenced, the Code has provided the option of using one universal standard for energy for energy compliance.
How effective the Step Code will be in reducing GHGs from buildings remains to be seen. For now, the energy code only applies to Part 9 buildings for the vast majority of the province that is not in Climate Zone 4. Also, with the stated target of net zero ready by 2032 and no interim targets, the BC Energy Step Code in its current form allows municipalities to stay pretty much where they are for another decade or so. Indeed, the guide to the Step Code recommends that – “at least until 2020 – local governments that are considering the application of the BC Energy Step Code on a community-wide scale should only require the Lower Steps”.13 Given the normally slow adoption of change within the building and development industry, the timelines of the Step Code may appear reasonable. However, when you consider that 15,000 scientist just issued a “Warning to Humanity” of catastrophic environmental collapse and stated “soon it will be too late to shift course away from our failing trajectory, and time is running out”, 14 we know we are up against the clock, and losing, on climate change. One can only hope that individual jurisdictions will show moral leadership and ambition, and move to the highest levels of the Step Code as quickly as possible.
A Singular Standard
We can see that the adoption of the Passive House Standard is increasingly being recognized by jurisdictions in BC as an effective way to reduce greenhouse gas emissions associated with buildings. While requirements vary between jurisdictions and building types, the Passive House standard is explicitly mentioned in new regulations in BC, as well as the Cities of Vancouver and North Vancouver, as meeting their most stringent requirements for energy use. Within the often-confusing patchwork of regulations, Passive House provides a single standard and methodology that can meet energy requirements in zoning and codes throughout the province. The Standard comes with straightforward energy modelling tools, a consistent methodology, construction best practices, and thousands of precedent projects to assist designers and builders. As municipalities and the Province increasingly strive to meet zero or near zero emissions targets for buildings, we can expect to see increasing reference in regulations and codes to Passive House. With this knowledge, architects, designers, developers, regulators and contractors have a roadmap for the evolution of the building industry in British Columbia in the climate change era.
Look for an expanded version of this article in the October 2018 issue of Construction Canada magazine.
1 Passive House Institute. Press Release. November 6th, 2017 https://passivehouse-international.org/upload/20171106_Pressemitteilung_COP23_Bonn_EN.pdf
2 Jason Packer. Recollective Consulting.
4 “Green Buildings”. City of Vancouver website. http://vancouver.ca/green-vancouver/green-buildings.aspx
5 “Green Buildings Policy for Rezoning – Process and Requirements”. City of Vancouver Bulletin. Amended April 28th, 2017 http://bylaws.vancouver.ca/Bulletin/G002_2017April28.pdf
7 “Passive House Guidelines for RS-1”. City of Vancouver guideline. November 3rd, 2015. http://guidelines.vancouver.ca/P012.pdf
8 City of North Vancouver, Official Community Plan, p.56 http://www.cnv.org/Your-Government/Official-Community-Plan
9 “Moodyville Area”. City of North Vancouver – Major Studies and Projects. http://www.cnv.org/property-and-development/projects-and-developments/major-studies-and-projects/moodyville-development-controls-process
10 Energy Step Code – Convenience Copy. https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/construction-industry/building-codes-and-standards/revisions-and-mo/esc-convenienceweb-april2017.pdf
11 Energy Step Code – Convenience Copy. Section 18.104.22.168 3) https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/construction-industry/building-codes-and-standards/revisions-and-mo/esc-convenienceweb-april2017.pdf
12 “BC Energy Step Code – A Best Practices Guide for Local Governments”p.50 https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/construction-industry/building-codes-and-standards/guides/bcenergystepcode_guide_v1.pdf
13 “BC Energy Step Code – A Best Practices Guide for Local Governments” p.37. https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/construction-industry/building-codes-and-standards/guides/bcenergystepcode_guide_v1.pdf
14 “World Scientists’ Warning to Humanity: A Second Notice”. BioScience. https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/bix125/4605229