Tag Archives: building

Analysis: Best Practices for Providing Effective Daylight in Mid-Century Modern Structures

DOCOMOMO_OREGON and the Northwest Chapter of the Association for Preservation Technology recently held an Energy Conservation Symposium that explored issues facing mid-century modern buildings: How can modern historic buildings comply with today’s energy conservation standards? Is it possible to maintain the integrity of the historic building materials and aesthetics while also meeting new energy conservation requirements?

At PMA we believe that while challenging, it is possible to maintain the integrity of these historic mid-century modern buildings and meet new energy conservation requirements. In an effort to explore this possibility, we submitted an abstract for the symposium, and Halla Hoffer, AIA, subsequently presented on Best Practices for Providing Effective Daylight in Mid-Century Modern Structures.

BACKGROUND
Effective daylighting can reduce both lighting and cooling loads while improving user comfort, satisfaction, and health. Despite plentiful glass, using daylight in mid-century modern building can be challenging. Glare and uneven light distribution can cause user discomfort and pose challenges to effectively daylighting spaces. Frequently, artificial lighting is used to balance lighting in spaces over lit by the sun, negating any potential energy savings. For existing buildings, the available methods to provide effective daylighting are limited by the existing constructions and configuration. To both preserve existing structures and provide ample daylight a critical question must be answered – what are the best practices for improving daylight in existing buildings? This study provides insight to daylighting existing structures, specifically, how light can be controlled and distributed in mid-century modern buildings with plentiful glazing.

1963 RESIDENTIAL TOWER
This study explores and analyzes how common daylighting strategies can be implemented on existing mid-century modern structures. The study focuses on a sixteen-story 1963 residential tower in Portland, Oregon, and explores how interior reflectivity, interior/exterior light shelves, shading, and glazing can impact daylight availability and distribution. The study looks at a variety of ways each strategy can be implemented and analyzes the results to determine best practices based on daylight distribution/availability, glare, lighting loads, and heating/cooling loads.
on Best Practices for Providing Effective Daylight in Mid-Century Modern Structures

TOOLS USED FOR SPECIFIC ANALYSIS
Emerging tools and technologies provide effective methods of analyzing hundreds of different daylighting simulations. Applications such as Grasshopper and Dynamo, which are visual programming environments for Rhinoceros 3D and Revit respectively, allow users to explore a variety of different design interventions and determine optimal solutions. Prior to starting the daylight analysis, we began with a “base geometry” of the existing conditions that we modeled in Rhinoceros 3D. We then developed a Grasshopper file to create daylighting interventions. For this study the interventions consisted of interior light shelves and exterior shading devices based on numerical inputs for shelf depth and height. Using Grasshopper in lieu of traditional 3D modeling allowed us to systematically test multiple variations of intervention geometry. In addition to studying how new geometries would impact daylighting we also studied how existing/new materials could impact daylighting performance.
on Best Practices for Providing Effective Daylight in Mid-Century Modern Structures

The daylighting analysis was performed using DIVA for Rhino, a plug-in that performs daylighting and energy analysis directly in Rhino. DIVA also offers several Grasshopper nodes, allowing the analysis to be controlled and managed directly in Grasshopper. For this analysis the primary results we extracted and used to measure performance included:

Annual Daylight: Percentage of time space receives at least 300 lux. This value can be mapped over the area under analysis. Typically, areas that receive 300 lux at least 50% of the time have the potential for daylighting.

Spatial Daylight Autonomy (sDA): Percentage of a space that receives 300 lux for at least 50% of the annual occupied hours. This metric provides a single number for quickly determining daylight potential. A value over 55 indicates that daylighting will be at a minimum nominally accepted by occupants. A value over 75 denotes a space where daylighting will likely be preferred by occupants.

Annual Sunlight Exposure (ASE): Percentage of a space that receives over 1,000 lux for at least 250 hours per year. High values indicate that the space may be overlit and cause glare/discomfort.

Daylight Factor: A ratio comparing light levels on the interior of the structure to the light levels on the exterior. Typically, a value under 2% indicates that the space cannot be adequately daylit, a value between 2%-5% is preferred for daylighting, and a value over 5% indicates that the space is well daylight, but may be overlit.

on Best Practices for Providing Effective Daylight in Mid-Century Modern Structures

CONCLUSIONS
Reflective interior surfaces can have a significant impact on daylight distribution.

Without any shading there is a high probability for glare according to ASE and DF values.

Interior light shelves alone can reduce the ASE values and the probability of glare.

Interior light shelves alone are not as effective as exterior shading devices in reducing glare.

A combination of reflective interior materials, interior light shelves, and exterior shading devices is the most effective method to provide adequate levels and even distribution of light.

Written and presented by Halla Hoffer, AIA, Assoc. DBIA / Associate

Abstract: Best Practices for Providing Effective Daylight in Mid-Century Modern Structures

When we think of energy conservation standards for our built environment an increasing amount of existing buildings do not comply with today’s standards. A large portion of these existing buildings are from the mid-century modern era. Additionally, mid-century modern buildings are approaching historic status, if not already there. This status compounds finding the best way to integrate current energy standards because aesthetic impacts to a historic resource must be kept to a minimum. At PMA we believe that while challenging, it is possible to maintain the integrity of historic mid-century modern buildings while meeting new energy conservation requirements. In an effort to explore this possibility, we have submitted an abstract for an upcoming Energy Conservation in Mid-Century Modern Buildings Symposium presented jointly by APT Northwest and DOCOMOMO_Oregon.
window-detail
ABSTRACT: BEST PRACTICES FOR PROVIDING EFFECTIVE DAYLIGHT IN MID-CENTURY MODERN STRUCTURES
Effective daylighting can reduce both lighting and cooling loads while improving user comfort, satisfaction, and health. Despite plentiful glass, using daylight in mid-century modern building can be challenging. Glare and uneven light distribution can cause user discomfort and pose challenges to effectively daylighting spaces. Frequently, artificial lighting is used to balance lighting in spaces over lit by the sun, negating any potential energy savings. For existing buildings, the available methods to provide effective daylighting are limited by the existing constructions and configuration. To both preserve existing structures and provide ample daylight a critical question must be answered – what are the best practices for improving daylight in existing buildings? This study provides insight to daylighting existing structures, specifically, how light can be controlled and distributed in mid-century modern buildings with plentiful glazing.

Emerging tools and technologies provide effective methods of analyzing hundreds of different daylighting simulations. Applications such as Grasshopper and Dynamo allow users to explore a variety of different design interventions and determine optimal solutions. This study explores and analyzes how common daylighting strategies can be implemented on existing mid-century modern structures. The study focuses on a 1963 residential tower in Portland, Oregon, and explores how interior reflectivity, interior/exterior light shelves, shading, and glazing can impact daylight availability and distribution. The study looks at a variety of ways each strategy can be implemented and analyzes the results to determine best practices based on daylight distribution/availability, glare, lighting loads, and heating/cooling loads.

Speaker Bio
Halla Hoffer, AIA, Assoc. DBIA
Associate / Peter Meijer Architect, PC

Halla is passionate about rehabilitating historic and existing architecture by integrating the latest energy technologies to maintain the structures inherent sustainability. Halla joined PMA in 2012 and was promoted to Associate in 2016. She is a specialist in energy and environmental management, as well as building science performance for civic, educational, and residential resources. Halla meets the Secretary of the Interior’s Historic Preservation Professional Qualification Standards (36 CFR Part 61).

Advocacy for Urban Character

Quebec

Quebec City is a beautiful, fascinating place. It is a place like no other North American city. Walking on the streets immediately transports you to a French provincial, charming town. Its’ citizens and language are French. Its’ foundations are literally built on the historic fortification walls. And as a result of the physical evidence of the historic urban fabric, Quebec City has become a World Heritage Site, the first in North America.

Strolling through Quebec City creates a direct experience with the history of the city, the region, and, in fact, the world because Quebec City was the debarkation and trade center for both England and France and the capital of a vast fur and trading region stretching west of the Mississippi River. To experience Quebec City is to experience urban history through the built environment, the streets, buildings, parks, and natural features. It is seemingly impossible to convey the connectivity of modern Quebec City to the historic events and people without the physical examples from its past.

Marquette Plaza (historic photograph)

The city’s character, like the character of many cities, resulted directly from advocacy for retaining historic places. Advocacy often begins with a few individuals thinking and acting against conventional wisdom. Or more appropriately, postulating positions and thoughts about preserving cultural aspects of the built environment long before the majority believe the places embody history.

It is not that the individual is smarter, or more prescience than the majority in determining the necessity of advocacy. But perhaps the urban environment has triggered an experience that resonates as a connection with the community. That moving through the built environment creates an evidence of knowledge within the individual, or group, causing a desire to offer the same opportunity for others in far future generations to experience the same connection to community.

Piazza d’Italia

So as a firm with a practice centered on design, science, and preservation, PMA has a profound interest in the built environment. In specific, an interest in preserving existing places for future generations. Advocacy is a natural outcome of our practice and we view advocacy as enabling future generations an opportunity to experience current urban places as significant cultural resources.

Buildings go through cycles of use, maintenance, and age. The first 30 years may be characterized as the new, adoration cycle. From 30 – 60 years old is the cycle of danger for buildings when use has caused wear, and system have reached the end of their life cycle, and age is not deemed old enough to be historic. The cycle after 60 years old is the celebratory cycle when dedication anniversaries are highlighted and resources are again invested.

James R. Thompson Center

It is the cycle of danger that is dependent upon advocacy. When the built environment has lost the luster of new, and the connection with community has waned, and when older generations cannot convey historic character to newer buildings, and the younger generation has not yet been taught the recent past; advocacy is needed to initiate the discourse and once again create the evidence of knowledge connecting buildings and urban fabric, building the character of our collective places. Whether as an individual, a group, or under the leadership of PMA, advocacy is critical to urban places, necessary for human existence, and crucial to healthy dialogues about the future of our cities.

Written by Peter Meijer, AIA, NCARB, Principal.