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Overview of Architectural Styles in Oregon: 1840s to 1970s

The City of Gresham applied for and was granted a CLG grant from the State Historic Preservation Office to increase community interest in historic preservation. The City felt that a presentation focused on architectural styles would be likely to generate some interest. They contacted PMA to find out if we would work within their budget and provide a powerpoint presentation geared towards citizens with no planning or architecture background, but also useful for City staff and historians. PMA was happy to be able to provide an overview of Oregon architecture styles from “settlement era” up until mid-1970s. The presentation highlighted the styles most likely to be seen in the Gresham area, especially residential and commercial uses. It was educational for our office to find those historic properties in Gresham and incorporate some of them into the presentation.

Use, Type, Style
It is difficult to understand style without an appreciation of the ways style can be overlaid on various types and uses of buildings. The USE of a building is its primary function. For instance, a church (use) might have a hall with steeple (types or forms) and be Neoclassical (style). The use or purpose of a building is strongly linked to its form, but even within a category of use such as residential, one might find various types such as “apartment block,” “bungalow,” or “four-square.” TYPE just means the basic form, so it is useful for historians to categorize these forms into expected sizes or arrangements of volumes. An apartment block is generally a simple rectangular building with several apartment units and a shared entry. A bungalow is simply a small house, one or 1.5 stories, horizontal in expression. Bungalows are often Craftsman in style, but a handful of other styles are sometimes used with a bungalow type. A four-square is a larger house, typically 2 or 2.5 stories, consisting of a somewhat square footprint with 4 rooms on each floor, and a broad front porch with columns or posts.

The building’s STYLE is determined by the architectural and ornamental details and exterior features applied to the basic structure. Styles change with the times. In fashion and out of fashion, some endure longer. The timeline included is generally reflective of Oregon architectural fashions. However, style also can be affected by technology- for example, the development of steel frame buildings allowed for a new style to emerge: Modernism. Older bearing-wall masonry construction only allowed for small windows set between structural wall areas. A proliferation of new building types, such as the geodesic dome, occurred in the Modern era.

We categorize buildings by type, use, and style when doing a survey of resources in a particular area. The data can be compared quickly and easily to data from other surveys, so we can see the patterns and history of development emerging in any particular area.

Stylistic Timeline of Architectural Styles in Oregon
From Vernacular Forms and Styles, to Renaissance Revivals, Northwest Regional Style and Post Modern, Oregon has a robust and diverse vocabulary of architecture. The stylistic timeline below is meant as a broad overview, highlighting key attributes per style listed, to help you identify your local and regional architectural resources.

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Written by Kristen Minor, Associate, Preservation Planner

The Form and Function of Lighting Design

When we experience an interior architectural space, lighting plays a large role in setting the mood and functionality of a space. No matter an existing, modern or historic building, light of a space is a critical aspect of great interior design. Lighting elements can be designed to enhance the space and architectural details, set the mood, and compliment furniture, color schemes, and art work. For spaces without an abundance of natural light, lighting design becomes even more critical design consideration. For a recent project, PMA designed lighting schemes for two historic four-story tall interior atriums.

The existing atriums utilize natural light from skylights above; however the original design provided no artificial overhead lighting in the space. During the winter months or at dusk and night, the light quality of space relies on the little ambient light from the skylights or artificial light from the surrounding rooms and halls. The light during these times is inadequate for the necessary function of the space. PMA was tasked with providing a lighting solution that would sensitively address the historic nature of the atriums and provide adequate visibility in the space.
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Defining the Project Challenges
The concepts for our lighting schemes were based on the intended function of each identical space. The focus of the design and specified need of the client was to provide lighting for evening social gatherings, networking, and overall entertaining. Lighting needed to be adequate enough for speakers presenting to a crowd and for listeners to be able to read any related literature. Therefore, it was crucial to design lighting schemes that could provide ample lighting for evening events without compromising the historic integrity and ambiance of each space. To provide a solution for our clients’ challenge, we considered the following when approaching our design for the lighting schemes:

  • How to provide power to the source of lighting without compromising the historic elements.
  • Designing for large volumes of vertical space: hanging lighting within the atrium versus lighting from the top; how the light travels in the space, how it casts down shadows, the reflections off the floor and other surfaces.
  • One atrium exhibits permanent hanging sculptures and art; the lighting design required minimal approach to integrated and highlight the sculpture without distracting from it.
  • Designing for and highlighting the atriums’ architectural details, like the cornices, in addition how to hide or incorporating other non-historic architectural details like the structural support columns.
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    Methodology for Design Solutions
    The prominent design goal was to increase overall light levels through a refined, modern scheme that would provide juxtaposition to the historic architectural elements and hanging sculpture. As in any historic project, it is important to avoid solutions that are faux historic, competing with, compromising, or confusing the original historic character. The few pragmatic design parameters defined by the client allowed for design freedom to provide several unique, distinct solutions. While creating our designs, PMA experimented with the type of fixtures (down lights, sconce, defused) and placement of these fixtures within the large volume of the atriums. PMA explored these options in a Revit model of the atrium spaces, which enabled evaluation of the design solutions through lifelike renderings that portrayed the quality and levels of light. Illuminance studies of lux levels provided a way to evaluate each design and provide refinement to meet necessary levels defined by the function of the space. Some lighting design options included:

  • Design lighting to highlight and contrast architectural features from surroundings, for example placing fixtures in the cove of architecture cornices located above openings within the atrium.
  • One atrium has a glass block floor element which could be illuminated from below to provide a dramatic light feature.
  • Accenting the verticality of the space with defused ribbon lighting set within the non-historic structural C-channels. This would transform these elements into elegant vertical lines leading the eye to the above skylights.
  • Pendant lights interspersed between sculptures would provide orbs of light to highlight elements of the sculpture. These fixtures would provide defused-light with optional downlights within the same fixture.
  • Suspended down lights at top of atrium with lights accenting sculptures from above and side.
  • Wall sconces to accents light and wash the atrium walls and columns; this would provide an overall glow to the space.
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    Scheme 1 unified serval lighting design ideas to provide different light level options in the space. Wall sconce lights provide general illumination of the space. Large circular hanging fixtures consist of defused tube lights and large circular defused downlights. Each group of fixture types can be controlled independently and dimmed to provide the ambience desired.

    Scheme 2 specifically works with the sculptures in the second atrium space. Vertical ribbon lights provide ambience illuminance of the space while concealing non-historic structural elements. Pendant lights hang interspersed within the sculptural elements. These have a defused light with an option for downlights. Each grouping of fixtures can be illuminated together or separately depending on the quality of light needed.

    Scheme 3 was chosen by the client and until announced must remain confidential. Stay tuned for the reveal.


    Written by Hali Knight.

    Means and Methods of Architectural Design

    On a recent trip to Italy, I couldn’t help but contemplate the progression of architecture styles across time and contemporary architecture’s divergence/evolution from past practice. Architecture, alongside art, has long reflected contemporary trends, culture, and politics. More than ever, contemporary architecture reflects our societies’ obsession with technology, efficiency, and value-engineering. As I stood within the walls of Carlos Scarpa’s Brion Cemetery, taking in the attention to detail and crafted experience of the space, I wondered if architecture would ever return to this level of craft, detail, and whimsy. It is hard to image Carlos Scarpa’s intricate and unique detail being created in the architectural world today. From my perception, the art of architecture on a mass scale is being transformed to a systems and science of architecture where unique, non-functioning, artful details are being abandoned as superfluous and cost prohibited.
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    A Paradigm Shift
    Great works of historic architecture were conceived by pen and paper as artistic minds envisioned each space on iterative gestural pages; translated from enigmas to sketches to drawings to reality. Materials were crafted by hand and details seamlessly integrated within each trade’s identity. Today’s paradigm shift toward Building Information Modeling (BIM), factory production, and intelligent building systems have transformed the means and methods of the tradition discipline. Traditional detailing known by each trade has been lost to time as architects and builders move to new systems. The design process has continued to evolve and transitioned to computer based iterative processes. This creates a new dialog where the computer program itself has an influence over the design.

    Architectural contemporary styles are named for the processes in which they were designed, such as Diagramism, Revitism, Scriptism, and Subdivisionism. These processes include designing in CAD, BIM, and other 3D programs, which can predominantly drive the design style and form. Architects and designers need to be aware of how architectural design is affected by each program’s restrictions and work flow tendencies. There can be a detachment for the final goal of the built form as we go down the virtual rabbit hole. The benefit of 3D modeling is that it allows designers to more fully comprehend form and its intersection with the overall building systems. However, if the design process is pushed into modeling without a strong concept, the objective can be easily replaced with creating a well-organized and systematic Building Information Modeling, instead of holistic architectural design.
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    Architectural Design and BIM
    BIM designs are based primarily of component systems that create efficient, intelligent, and informative models. Designers can easily draw schedules and quantities that greatly speed up processes, however in the design process, focusing on components can also create a disassociation from the whole building and design concept. The translation of an artistic gesture of a material or space can easily be lost in the clunky world of 3D representation and restrictions.

    I am certainly a proponent of BIM, but I am also an advocate of preserving the art and craft of architecture. BIM is a terrific for understanding buildings in their 3D form as a composition of components and systems. BIM’s intelligence allows for continued updating of schedules and quantities, allowing for time efficiency. However, these components are limited to the software’s modeling options and the designer’s skill at modeling. The virtual world is still not an accurate representation of all the properties of building materials or their structural capabilities. In other words, BIM cannot be a means from the start to the end. Our profession is obligated to continue to push for high design standards and syndicate and extrapolate. I continue to see architecture that either allows BIM to drive design or prioritizes efficiency and value-engineering over quality of design. As BIM evolves within architecture as a means to design, I hope it can assist designers in their creative process and challenge our profession’s boundaries.

    Written by Hali Knight, Architect I

    Sources
    Prospect Magazine
    Archdaily
    DI

    Using Revit for Historic Architecture

    Revit is used widely for designing new architecture and for documentation of existing structures. When first looking at Revit one may assume that it is tailored for use with contemporary designs. The default ‘Families’ (the term Revit uses to describe all types of elements from furniture to windows, doors, annotation symbols, wall constructions, etc.) are all generic to new construction. Despite the pre-set generic components, Revit’s strength lies in the ability to create custom ‘Families’ and its capability of tracking both three dimensional design as well as linked information about components. When used correctly Revit can be a powerful tool for building assessment and historic renovation. At PMA we have found several tools in Revit that can help us accurately show historic elements, track information about conditions, show repair strategies, and graphically present data.
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    When working on historic structures it can be very important to accurately show existing elements. We often need to indicate exact pieces of terra cotta that require replacement or how a stone entry stair is configured so that the cost for replacement stones can be correctly estimated. We frequently create custom ‘Families’ to accurately show historic detailing. ‘Families’ of all types can be created to refine a model and add historic detail. Some of the common custom elements that we create include windows with historically accurate profiles, stacked walls that let us show terra cotta banding and differentiation in materials/wall thicknesses, complex historic roof structures, and custom patterns that match existing stonework. By adapting the generic Revit ‘Families’ and creating our own we are able to accurately represent historic features and structures.

    Capabilities
    One of Revit’s most useful capabilities is its ability to record and track information about building components. Unlike earlier drafting and 3D modeling applications, Revit can store information about material finishes, specification references, and much more! In Revit you can assign ‘Parameters’ to ‘Families’. ‘Parameters’ are used in a variety of different ways – but one of the most useful we’ve found is their ability to track the condition of specific building elements. For example, when we perform window surveys we can assign ‘Parameters’ to all of the modeled windows that describe the typical deficiencies observed. For each individual unit we can then record what deficiencies were discovered in the field. Once all of the information has been added to the Revit model you can create schedules in Revit to describe the condition of each window unit and total quantities. The information can be extracted from Revit and into spreadsheet software to analyze the data, present trends, and identify repair scopes for individual units.
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    Using Fliter’s
    Revit’s ‘Filter’s’ function is another tool that we use in conjunction with ‘Parameters’ to better understand and present information that we’ve recorded in the field. Filters allow one to alter the graphics for components based on their ‘Parameter’ values. For example we commonly use ‘Filters’ to graphically show the condition of a building’s windows after a survey. We do this by creating a condition ‘Parameter’ where a value can be assigned to each window, for example, good, moderate, and poor. We can then use filters to highlight all of the windows in good condition green, those in moderate condition yellow, and those in poor condition red. Unlike a window schedule which may require some analysis – the color coded elevations Revit can create with ‘Filters’ are easy to understand and an excellent tool for presentations.

    At PMA we have found Revit to be an invaluable tool that we use day to day for a variety of uses including 3D modeling, displaying point clouds, rendering, tracking information, and presenting data. Revit is a capable tool and with a little creativity one can tailor the application to complex historic projects. The ability to create complex custom ‘Families’ that track data about the structure make it possible for our office to efficiently record, analyze, and present date we observe in the field – bringing projects all the way through development, documentation of construction documents, and construction itself.

    Review our ongoing building envelope project that utilizes Revit.

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    Written By Halla Hoffer, Associate, Architect I

    Portland’s Architectural Heritage from the Recent Past

    In March 2015, we wrote about PDX Post Modern and Mid-Century Modern architecture, which to our eyes was being referenced by local architectural firms for their new designs located at the Burnside Bridgehead and elsewhere. A year later and the City of Portland is continuing to build, build, build especially around the Burnside Bridgehead. In addition, cries for the demolition of a Post Modern icon of architecture: Michael Grave’s designed, Portland Public Service Building, have turned into a proposed $200 million design-build project. Has Portland come to appreciate its architectural heritage from the recent past?

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    Portland Building, PacWest Center, Koin Tower

    Before definitively answering, let’s look at efforts to repair and utilize some of Portland’s recent past architectural resources.
    DoCoMoMo_Oregon, a local chapter of DoCoMoMo_US, is a non-profit organization dedicated to promoting the interest, education, and advocacy of the architecture, art, landscape, and urban design of the Modern Movement. Recently the Board voiced concerns for the type of alterations proposed for the late modern (post modern!) PacWest Center designed by Hugh Stubbins & Associates / Skidmore, Owings & Merrill, which underwent a Design Advice. John Russell, the original developer of the project who chose Hugh Stubbins as the architect, from a shortlist that included Philip Johnson and Minoru Yamasaki, provided testimony that agreed with the design team that the retail in the building isn’t currently working, but that the building’s design isn’t the major contributor. Overall, the Design Commission encouraged the design team to treat the PacWest Center like a historic building, and use the Secretary of the Interior’s Standards as an approach for the renovation.

    The Koin Tower, designed by ZGF Partnership in 1984, is one of the most prominent buildings in Portland’s downtown rising sky-line, and an example of Post Modern architecture. It is Post Modern with whimsical lines and historical references to Gothic, Spanish, and Deco architectural characteristics. (King, 106) However, unlike the Post Modern Portland Building (interiors designed by ZGF), the Koin Tower has been accepted for its architectural whimsy in a place with a known tag line, “Keep Portland Weird.”

    And on a smaller scale that truly connects to placemaking, the Lovejoy Fountain Pavilion designed by Charles Moore in 1962 as part of Lawrence Halprin’s fountain sequence was thoughtfully restored in 2012.

    Appreciating the Recent Past
    So, has Portland come to appreciate its architectural heritage from the recent past? While these four examples offer a glimpse of optimism towards the maintenance and rehabilitation of architecture from the recent past, there is still an uphill battle towards the preservation and rehabilitation of Post Modern, Modern, and historic architectural resources. This is not an argument to save every resource, but it’s our responsibility to our present and future communities to have places rich in architectural resources from different movements of history- architecture rich in diversity. For architectural diversity contributes to our place making, culture, and identity. Let’s Keep Portland Architecture Weird by both adding to and maintaining and rehabilitating.

    Lovejoy Pavilion

    Lovejoy Pavilion

    Written by Kate Kearney, Marketing Coordinator

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    King, Bart. An Architectural Guidebook to Portland. 2nd ed. Corvallis: Oregon State University Press, 2007. Print.

    Post Modern Building Materials Part One

    Advances in science and material properties have always played a role in the development of building products. Postmodernism fueled the advent of several new building materials including Glass Reinforced Polyester (James Stirling, Olivetti Training Center, c.1972), Insulated Exterior Metal Panel Systems (Richard Meier, Bronx Development Center, c.1979), Dupont’s Fabric Tensile Structures (University of Florida Gainesville, O’Connell Center, c.1980), polycarbonate sheets (Kalwall, et.al.), pre-fabricated brick panel systems, and many other new construction technologies.

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    Richard Meier, Bronx Development Center, 1977


    Post Modern Building Materials and Life-Cycle
    Like any new technology or building material, the life span of postmodern materials is now known but there is a lack of case studies and journalistic papers describing the failure mechanisms, and more importantly, how to repair, retain, or preserve the exterior materials. On one level there is an inherent impermanence of the original materials based on a default decision making process that limited a building’s longevity to a twenty-five (25) year life-cycle. On another level, the façade of the Postmodern building incorporates building systems or individual components that are neither produced nor assembled currently in similar manners due to improvements in technology and building envelope science. In either case, the process and method of building envelope repair could dramatically or minimally impact the exterior character of Postmodern structures.
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    Aldo Rossi, Theatro Delmondo, Venice 1982


    There are some Postmodern structures, despite the polarizing opinions regarding the aesthetic values, that are iconographic examples of the high-end of Postmodern style. Included with those structures named above, are the Portland Building (Michael Graves, c. 1984), Piazza d’Italia (Charles Moore, 1982), and Theatro Delmondo, (Aldo Rossi, Venice 1982) to name a few. Rossi’s Theatro Delmondo poses an even more challenging theoretical debate as to whether or not to preserve or repair the structure since the theater was built as a floating temporary stage set.

    Rehabilitation and Postmodern materials
    The rehabilitation of Postmodern materials is compounded by the lack of physical or chemical stability in the original product (e.g. color fading or material breakdown by UV light); changing urban context and surrounding development; inadequate original construction means and methods, and lack of precedence – Postmodern buildings are just now reaching the end of their design life-cycle. Proposals to improve envelope performance are challenged in finding products that will improve performance and retain the aesthetics of a Postmodern building. Given these challenges, is the proper repair, rehabilitation, or conservation of Postmodern structures to retain the appearance of insubstantial material installed incorrectly? Or should any new work, often entailing proposals for replacing the building facades, to discount the design appearance and fix the problems regardless of the impact.

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    ZGF, Koin Center, 1982


    Moving forward, there are precedents set by the early and current challenges associated with mid-century modern structures that can be followed. For example, circa 1960 glass curtain wall upgrades have created methods to retain the exterior appearance while upgrading the thermal efficiency of the system or conversely, left the existing original curtain wall in place and upgrade the mechanical system and distribution system as both more cost effective and more energy efficient over the life of the building. The solutions towards postmodern materials will similarly be led by research, initiative, and innovation. Engaging the manufactures in the dialogue is essential, particularly when replacing a failed product is critical to retaining the building design character.
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    James Stirling, Olivetti Training Center, 1972


    Unique Challenges
    There are unique challenges with Postmodern buildings, but as is the case with all new materials and systems, developing a strategy of research, methodology, and documentation will result in extending the life-cycle of these provocative structures.
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    Portland Building

    Written by Peter Meijer, AIA, NCARB / Principal

    PMAPDX 2015 Year in Review

    HAPPY HOLIDAYS!!

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    Wishing you a holiday season filled with cheer and delight from Peter Meijer Architect.

    As we look back over the past year and reflect on our completed, on-going, and upcoming projects, we’d like to take the opportunity to say we have truly enjoyed collaborating and communicating with you.

    2015 PROJECT HIGHLIGHTS
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    PMA HAPPENINGS
    Peter Meijer AIA, NCARB, was a Presenter at the RCI, Inc. 2015 Symposium on Building Envelope Technology. He presented on, When Field Performance of Masonry Does Not Correlate with Lab Test Results. PPS Grant High School was the case study presented.

    Kristen Minor, Preservation Planner, is the newest member of the City of Portland Historic Landmarks Commission.

    When Field Performance of Masonry Does Not Correlate with Lab Results

    First presented at RCI 2015 Symposium on Building Envelope Technology, Nashville, TN

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    Background
    When it was completed, Grant High School was typical of the high schools constructed by Portland Public Schools in the pre-World War II era. In addition to being an extensible school, including educational buildings constructed between 1923 and 1970, the school was also reflective of fire-proof construction through its use of a reinforced concrete structure with brick in-fill. (Portland Public Schools, Historic Building Assessment, Entrix, October 2009)

    Over the last fifteen years, Portland Public Schools (PPS) noted an accelerated degree of masonry face spalling on the original 1923 main building and 1923 Old Gym particularly when adjacent to concentrated sources of surface water. Other areas of spalling were not as obvious including protected wall surfaces. The masonry spalling was not occurring on later additions including the north wing (circa 1925), south wing (circa 1927), and auditorium building (circa 1927). Upon closer visual examination, it was observed that individual units were failing in isolated protected areas of the wall surface. Failures in such areas could not be accounted for under direct correlation of heavy water intrusion and typical failure mechanisms.

    The failure of the brick was potentially due to a number of separate or cumulative conditions including 1) excessive water uptake by the brick; 2) sub-fluorescence expansion of salts in the masonry, 3) freeze thaw; 4) low quality of the original 1923 brick; and 5) the application of surface sealers preventing water migrating to the exterior surface.

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    Field Investigation
    In order to determine if the damage to the masonry was deeper than the surface, several wall-lets, an invasive exterior wall opening, were performed confirming the assembly of a multi-wythe masonry wall constructed in a typical fully bedded bond course with interlocking headers and no cavities between the first three brick courses. Hooked shaped, 3/32” gage, steel wire masonry ties in alternating courses and approximately twelve inches (12”) on center ties were found to be in good condition with no deterioration. The absence of corrosion on the in place brick wire ties indicated that little moisture was present inside the multi-wythe wall.

    As a result of the hypothesis and field observations, it was prudent to conduct a series of lab tests to the brick, mortar, and patch materials to assist in the determination of 1) the quality of the brick; 2) the physical composition of the brick; 3) the quantity of naturally occurring compounds in the masonry and mortar, particularly salts in the masonry; and 4) the quality of the mortar. The findings would help narrow the potential cause of the spalling and lead to a more focused repair and maintenance process. Bricks were removed for testing of Initial Rate of Absorption (IRA – a test for susceptibility to water saturation) freeze thaw testing, and petrographic analysis, a way to determine the inherent properties of the clay and manufacturing process. Both pointing and bedding mortar samples, as well as, the previous patching material were removed and also tested. To rule out damage caused by maintenance procedures, faces of the brick material were sent to determine if sealants were used on the brick and, if present, determine the sealant chemical makeup. The presence of a surface coating may lead to retention of water within the brick and thus prevent natural capillary flow, natural drying, and water evaporation.

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    Testing & Results
    Samples sent to the lab for coating assessment were analyzed via episcopic light microscopy, and Fourier- Transform Infrared Spectroscopy (FTIR) per ASTM D1245 and ASTM E1252. The results found no hydrocarbon or organic formulations used on the surface of the brick refuting the hypothesis of a surface sealer.

    Following modified ASTM standards, a 24-hr immersion and 5-hr boil absorption test on the brick were performed. The brick have a very low percent of total absorption at 9.5% for the 5-hr boil and 7.5% for the 24-hr test. The maximum saturation coefficient is 0.79 which is 0.01 over the maximum requirements for Severe Weathering bricks recommended for Portland climate (ASTM C216-07a Table 1). The Initial Rate of Absorption (IRA) is 5.7g/min/30in2 which equates to a very low suction brick or brick with low initial rates of absorption. The freeze thaw durability tests resulted in passing performance. All of these tests refuted the hypothesis that freezing temperatures were the cause of masonry spalling.

    A brick material analysis was performed in general conformance with ASTM C856, ASTM C1324 (masonry mortar) and included petrographic analysis, chemical analyses, x-ray diffraction and thermogravimetric analysis. Samples were analyzed under a polarized light microscope for information such as materials ratio and presence or absence of different deterioration mechanisms. These tests were used to assess the overall quality of material, presence of inherent salts, excessive retempering, cracking, ettringite formation, and potential alkali‐silica reactivity.

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    The Petrographic Characterization resulted in the most unusual findings and the most relevant results related to the observed failures. The polarized light microscope indicated carbonate based salt crystals seeping into the masonry from the mortar. No sulfate based salts, typically associated with the clays used for making brick, were present. Furthermore the inherent properties of the brick showed very small rounded voids and interconnected planer voids. Planner voids result from poor compaction during the raw clay extrusion process prior to firing.

    Performance of brick in the field is a result of both material properties and resistance to micro-climates within the brick’s capillary void structure which cannot be repeated in the lab. Studies have shown a connection between small voids in the material property and susceptibility to longer water retention near the surface. With natural absorption properties, the brick is taking in a small quantity of water in very small pores. 24-hour immersion results are very low (7.5%). Publication of more in-depth studies correlates maximum saturation values for brick with low 24-hour immersion values. The effect of low immersion values and small quantities of absorbed water may increase the susceptibility in brick with small pore structure to freeze thaw failure.

    The presence of salt migration out of the mortar and into the brick, plus small pore structure and low immersion values, combining with a cleavage plane resulting from manufacturing are contributing to the Grant High School brick spalls. Brick with smaller pores are less capable of absorbing the expansive forces of freezing water and drying salts. Interlaced pores creating linear plains parallel with the face of the brick create stress failure points resulting in surface spalling. Since the characteristics of the brick resulted from the firing and manufacturing process, the brick will remain susceptible to the failure mechanisms.

    Conclusion
    Field observations of masonry failures generally correspond with known failure mechanisms. However, it is not unusual that further analysis is necessary to confirm in-field performance and that typical laboratory test results are in conflict with in-situ performance.

    The best corrective action is to minimize the amount of surface water and proper mortar joints and mortar composition. Additional spalls are likely to occur in the future due to the accumulation of expansive forces over a long period of time. Replacement of the spalled bricks is recommended over further patching. Leaving spalled brick in place will continue to worsen the condition over time and affect adjacent brick.

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    Written by Peter Meijer, AIA, NCARB, Principal

    Navigating the Historic Tax Credit Application

    Historic Tax Credits were founded in partnership with the National Park Service (NPS) and the Internal Revenue Service (IRS) in 1986. As one of a number of incentives to help owners preserve historic properties, Historic Tax Credits have since become the premier financial incentive towards the rehabilitation of income-producing historic properties. Historic Tax Credits can be used for older, non-historic properties as well, so long as they are income-producing, at a lower credit amount. An owner can receive a 20% rehabilitation tax credit for the amount spent on the qualifying rehabilitation of a National Register-listed property, or 10% tax credit for the amount spent on the qualifying rehabilitation of an older property with no historic status.

    There is a minimum threshold of rehabilitation investment that must be met in order to qualify. Rehabilitation project costs must be equal to the Real Market Value (as assessed by the local tax authority) minus the value of the land or $5000, whichever is greater. Rehabilitation Tax Credits for tax-exempt historic properties are possible provided that the investment partner using the tax credits is a for profit, tax paying entity. Typically, separate Limited Liability Corporations are established through which rehabilitation funding flows to the project.
    Pacific-Tower-Tax-Credits20% Rehabilitation Tax Credit
    The most common use of historic tax credits is the 20% Rehabilitation Tax Credit. To qualify for the 20% historic tax credit a property must be listed on the National Register of Historic Places either individually or as a contributing resource within a historic district. Properties must be a building as defined by Treasury Regulation 1.48-1(e), income producing, and undergo a certified rehabilitation process, which is evaluated by the NPS and the State Historic Preservation Office (SHPO). This process includes the completion of a three part application: Part 1-Evauation of Significance (not typically necessary if the building is already on the National Register); Part 2-Description of Rehabilitation; and Part 3-Request for Certification of Completed Work. Once completed and approved by the NPS the 20% tax credit can be claimed for the tax year in which the property was certified by the NPS. Tax credits can be taken in phases as well, as long as each phase meets certain conditions.

    10% Rehabilitation Tax Credit
    To qualify for the 10% rehabilitation tax credit a property must have been built before 1936. Properties eligible for the 10% tax credit must be buildings, income producing, non-residential, and remain on the original site. Historic properties that have been relocated do not qualify. Other conditions include the retention of at least 50% of the external walls, at least 75% of internal and external walls, and at least 75% of the internal framework. Unlike the application process for the 20% Historic Tax Credit, there is no formal review process or certification. However, the tax credits are redeemed the same way. Buildings listed individually or contributing resources within a Historic District on the National Register of Historic Places are not eligible for the 10% tax credit.

    Current Trends
    The staff at PMA have years of experience navigating the Historic Tax Credit application, placing properties on the National Register of Historic Places, and working with the State Historic Preservation Office and the National Park Service to assure the rehabilitation project qualifies and receives historic tax credits.
    US-Custom-House-Tax-Credit
    From initial application of Part I through final certification of Part III, 180 days or more can elapse. Current development practices and financial investment processes place pressure on the development schedule to initiate rehabilitation prior to final approval by the National Park Service. Early construction places the tax credit under risk and final approval can be withheld pending review of all rehabilitation impacts. Market demand for open space with exposed mechanical, electrical, and plumbing systems is creating a trend in rehabilitation of historic properties to expose these functional systems.

    PMA’s experience in working with the market demand and reaction to the trend by SHPO and NPS, can provide owners with advice on where reviewers will be more stringent. PMA has worked with NPS when a Condition of Approval was placed on the submitted Part 2 Description of Rehabilitation requesting alteration of completed ceiling conditions throughout the building in occupied space. Although the owner did know that construction prior to approval was a risk, they also needed to have some spaces complete in order to retain certain tenants and meet the financial loan terms. PMA sought a compromise with NPS retaining completed ceilings, but altering the design intent and finish in those spaces not yet complete in order to meet the new Condition of Approval.
    usch_Ground Floor_Northeast Room (Viewing Northwest)
    Similarly, PMA has noted in the Part II application process an acceptance of exposed fire sprinkler lines and exposed conduits but resistance to exposed ductwork and exposed cable trays. Whereas it could be argued that exposed mechanical and wiring systems are akin to exposed electrical systems in that the exposed work does not have a long-term impact on the historic walls, floors, and ceilings, the combined affect changes the subjective visual impact from NPS perspective.

    Each of the above trends requires diligent documentation and on-going discussion during the construction process, which, in itself, can be very fluid and entail rapid changes. The tax credit consultant must be skilled in communication and work with both the development team and tax credit reviewers.

    PMA Technical Assistance
    PMA is proud to undertake historic tax credit commissions as these projects have been a great way for our office to combine our specializations in architecture and preservation. Over the last five years, PMA has completed numerous Historic Tax Credit applications throughout Oregon and Washington. Overall, Historic Tax Credits have proven to be vital to the financial proforma and successful investment strategy to preserve and rehabilitate historic properties.
    Pac-Tower-Tax-Credit

    Written by Peter Meijer AIA, NCARB, Principal / Kristen Minor, Preservation Planner / Brandon Grilc, Preservation Specialist

    Assessing Union Station to be Part of Our Future

    Portland’s Union Station is the only major railroad station built in Oregon, and one of the oldest major extant passenger terminals on the West Coast. From its inception, Union Station has functioned as a major transportation link to Portland and the west coast, with a continued vital role to play in future rail and multimodal transportation planning.
    Union-Station-Historic-photo
    A Sense of Place
    Critical to adapting Union Station, and other historic structures, for current and future use is to thoroughly understand key elements and components that convey the sense of place and rich history of the structure. A deeper understanding enables informed decisions to be made about the potential of key characteristics to remain for future generations. Union Station was constructed between 1892 and 1894 and was designed by Van Brunt & Howe architects in the Queen Anne style with Romanesque detail. From 1927 thru 1930, the Main Concourse was modernized by Portland’s internationally known architect, Pietro Belluschi, to reflect the streamline era of rail technology. Like the original 1892 elements, the Belluschi modernization’s are equally important stories to tell.

    Creating a graphic document annotating “changes over time” is an essential tool for evaluating how Union Station has adapted to improvements in rail technology, fluctuations in passenger volume, cultural shifts regarding train travel, as well as modifications to specific architectural elements that impact the historic integrity and interpretation of original design intent.
    Union-Station-Report-Outline-pg2
    Methodology for Assessment
    Our method of developing the graphic drawing is to compare historic floor plans and historic photographs to current plans and images through a process of layering plans from different eras over one another and drawing the altered, or missing, elements (e.g. walls, furniture, spaces, etc.) in different colors. This methodology provides an easily interpreted floor plan. The use of color enhances the image and creates a visual record of both changes and original historic fabric. In reading the graphic drawing, it becomes readily discernible that changes include: wood floors replaced with concrete and new floors added; openings in the main concourse were moved and enlarged; the women’s waiting room and toilet were removed to widen the south hall, the stairs were renovated, and a new baggage counter was constructed. The covered concourse was glassed in and a section was made into the First Class Lounge, which remains today. And in the 1940s, a nursery, or crying, room was added.
    Union-Station-PMAPDX-drawing
    What is fascinating about the history of a building like Union Station, is that the rail lines and street patterns are also integrated with the function and use of the structure and have changed over time as well. The construction of Union Station came soon after Portland was fully connected by rail in 1883 to California, Montana, and rail lines running to the East Coast across the U.S. The Spokane-Portland-Seattle rail connection was finished in 1908. In 1922, Union Station became accessible to all major passenger railroads operating through Portland.

    When originally constructed, six passenger car rail lines approached the rear of Union Station. The waiting platform consisted of planks on dirt with no canopy. The block across from Union Station consisted of a small restaurant, bar, other stores, and stables. A five foot iron fence bordered a large lawn and sidewalk to the south and west of the station. The High Shed, a large two-story metal shed was the first canopy built to cover the passenger platforms and extended perpendicular to the station. Under this High Shed, two smaller scale platform canopies were erected paralleling the tracks. A mail canopy was built at the north end of the building in 1915.

    By 1920, the block across from Union Station’s main entrance had been converted to parking to relieve congestion. As automobile use increased throughout the city, parking configurations were constantly changing over the years. By 1923, an elevated walkway was built to connect the Broadway Bridge to the main entrance.
    union-station-pmapdx-changes-overtime

    With the introduction of larger diesel locomotives and potential for high speed rail along the northwest corridor, the track, platforms, and canopies have had to be modified. Safety and accessibility have also driven the need for changes and modernization. Documenting these alterations with graphics, provides a foundation from which to advocate for further refinement while recognizing historic precedent and protection of historic elements.

    union-station-pmapdx-historic-photo

    Written by Peter Meijer, AIA,NCARB, Principal

    PMA is part of the DOWA-IBI Group team for this exciting PDC Union Station Renovation Project.