Passive House Facade Design and Construction: Performance-Based Criteria Allow Flexibility While Reducing Energy Consumption

Koehl, Louis, AIA

Passive House Facade Design and Construction

Performance-Based Criteria Allow Flexibility While Reducing Energy Consumption

Paper by Louis Koehl, AIA, CPHD

Presented on August 5, 2020 at Facade Tectonics 2024 World Congress

Overview

Abstract

Buildings account for over 40% of global emissions (GlobalABC, 2018). Growing populations and higher standards of living are increasing pressure on the built environment to expend more energy to meet occupant’s demands making it critical that architects envision buildings to maximize energy efficiency without sacrificing design flexibility and occupant comfort. This requires a comprehensive approach to facade design that takes into consideration thermal conductivity, solar heat gain, air-tightness, vapor control, window performance, aesthetics, and more. By relying on performance-based goals rather than prescriptive standards, Passive House requires hyper-efficient envelopes while still allowing the design team the flexibility to respond to a given project’s unique context and client requirements.

Handel Architects is a New York based architecture firm working with the Passive House standard to design high-rise residential buildings with diverse occupancy groups. This paper will provide an overview of the Passive House performance criteria including maximum allowable heating, cooling, and overall source energy demands, air-tightness, and thermal comfort criteria. It will demonstrate how these requirements impact building envelope design by examining two detailed case studies and providing a look at the office’s upcoming Passive House projects. Each example will examine how a focus on whole-building performance criteria – rather than prescriptive solutions – allow the design team flexibility to respond to the client’s requirements and the project’s specific occupancy, context, budget, aesthetics, etc.

The challenges of designing extremely efficient facades results in innovative approaches that can be applied to all projects, even those without clear sustainability objectives. The following case studies will be examined:

Case Study 1: The House at Cornell Tech – Completed in 2017 on Roosevelt Island in NYC, this 352-unit residential tower is clad with a prefabricated aluminum panelized facade. It was the tallest and largest certified Passive House in the world when completed.

Case Study 2: Sendero Verde – A multi-phased three building mixed-use development with over 700 units of affordable housing in East Harlem. Primary facade types include hand-laid brick cavity wall and EIFS. The project is currently under construction.

Authors

Louis Koehl, AIA, CPHD

Project Architect

Handel Architects

lkoehl@handelarchitects.com

Keywords

masonry facade, air infiltration, energy efficiency, thermal break, energy and carbon, sustainability, design processes, codes-standards-rating systems

Background

In May of 2019, the Anthropocene Working Group voted to designate a new geologic epoch, the Anthropocene, an era in which people have become a major geological force (Subramanian, 2019)