Brick Notes

INTRODUCTION  
The scale and materiality of brick have always been prompts for the architectural and constructive imagination. Bricks are small enough for most to grasp in one hand, but they allow for unlimited potential configurations when stacked or arranged. The manufacturing process for brick can produce variations in color, texture, and material properties. Bricks encourage play with the material, in the sense of exploration of stacking configurations, bond patterns, corbelling techniques, and a myriad of possible compositions. The imaginative power that we attribute to brick is exemplified in the fact that Lego bricks are called “bricks” and not “blocks” or “units”.  

There are of course many architectural examples of creative applications of brick. To cite just a few: Alvar Aalto used discarded “clinkers” in his exterior wall construction at Baker House (Cambridge, MA) and experimented with a variety of bond patterns on the Muuratsalo Experimental House (Finland). The University of Virginia campus has several garden walls of curved single wythe brick, in serpentine form, from the sketchbook of Thomas Jefferson. More recently and closer to home, Billie Tsien and Tod Williams used green glazed brick on Skirkanich Hall at Penn. A list of unique uses of brick in architecture, near and far, would obviously be much longer.  

Within this volume of CONTEXT, other contributions discuss the question of what a brick wants to be, and perhaps what a brick needs to be today. But what if you wanted to explore how brick becomes those things? To move from the design possibilities inherent in brick and to learn more about its construction and detailing? I would like to delve a bit into a type of writing that is generally unexplored — the “technical note”. Similar in some ways to a detailing manual or a book of design standards, the technical note seems unique in its scope and breadth. This essay is part review, part personal history, and perhaps part nostalgia for printed materials (a little more on that later). The topic brings together several threads of thought for me — how we communicate technical information in support of architectural goals; how we learn while practicing architecture; and the particular flexibility and imaginative power that we attribute to brick.  

WHAT ARE THE TECHNICAL NOTES? 
Let’s assume that your particular brick wants or needs to be an arch. You would have an interest in learning how to design, detail, and construct one. If I needed to detail an arch, I would turn to Technical Note 31, Brick Masonry Arches, published in 1995 by the Brick Industry Association (BIA). Technical notes are a genre of architecture writing and, while not exactly a lost art, the genre doesn’t receive the respect that it might deserve.  

When I was a younger architect, we had a thick binder full of the “Brick Notes” in the office. These were an indispensable resource, with a wealth of information on construction detailing, but also (and perhaps surprisingly) on history, terminology, and construction practices. The term “technical note” seems so dry as to be uninteresting and not worthy of consideration except for strictly utilitarian matters. But the brick notes themselves — the collected “Technical Notes on Brick Construction” compiled by the BIA — bely this understanding. For the BIA, the notes represent a way of communicating proven construction methods and educating design and construction professionals. In my experience, the technical note format is an effective way for architects (in particular younger professionals, but really of all experience levels) to build a vocabulary of construction terminology and an understanding of details. Much more than a description of standard details, the brick notes put the uses and forms of brick in a larger context. Browsing through and working with the information in the notes, one begins to see how a current project might be part of a larger tradition of construction, and also where it might make sense to deviate from that tradition. The brick notes provided a foundation of information that allowed for imaginative — but feasible — construction of details. 

Starting with Technical Note 1, Hot and Cold Weather Construction, and running through to Technical Note 48, Sustainability in Brick, the Technical Notes currently comprise 86 pamphlet length expositions on brick topics. (Some of the notes have been broken down into subtopics over the years, for example, Note 6 Painting Brick Masonry and Note 6A Colorless Coatings for Brick Masonry.) There are so many Technical Notes in part because we can envision brick being employed in so many different ways and performing a variety of architectural functions.  

THE BIA DESCRIBES THE BRICK NOTES IN THIS WAY:  
Technical Notes on Brick Construction are recommendations on the use of fired clay brick. Drawings, photographs, tables, and charts illustrate appropriate topics. They are explicitly written for fired clay brick which are manufactured: 

• from clay, shale, or similar naturally-occurring earthy substances, and 

• with a firing process that creates a fired bond between the particles of the brick. 

The properties of fired clay brick and the clay brick masonry made from them were used to establish the recommendations in these Technical Notes. Using these recommendations with other products that are not manufactured as outlined above may not result in the same performance associated with fired clay brick masonry. Further, use of these Technical Notes for the design, installation and maintenance of construction built with other products may in fact be detrimental to those products and the building on which they are installed. Thus, BIA does not advise the use of these recommendations with other products including but not limited to those claiming to be similar to fired clay brick products such as “fly ash” brick, concrete brick and other unfired or non-clay brick (https://www.gobrick.com/resources/technical-notes).  

Briefly exploring just three of the 86 brick notes will give a sense of the range of information available, and the benefits, and maybe some limitations, of the technical note genre. And, yes, we will get to that arch!  

THREE SPECIFIC NOTES 
Technical Note 9 Manufacturing of Brick (December 2006) 
Technical Note 9 provides an in-depth discussion on the process of turning raw materials into finished brick. As architects, we often select brick based simply on the appearance of samples, but the visual and tactile qualities of the final brick are the result of a myriad of factors. These factors include the natural characteristics of the mined clay or shale material but also specific decisions made within the manufacturing process — such as whether bricks were placed front-to-front or front-to-back while firing. The note is full of illuminating and sometimes surprising facts about the brick manufacturing process. Did you know that “de-hacking”, or the unloading of the kiln following brick firing, is often performed by robots?  

For most design professionals, materials just “show up” at the construction site. As we work to reduce embodied carbon in our building designs, this note provides a timely reminder of the need to better understand the circumstances of material production and transportation prior to arrival at the job site. Material production and material geography impact environmental responsibility in ways that are not always well understood during the design process. Note 9 does contain a descriptive section on the environmental responsibility of brick manufacturing, describing the general efficiency of the process. It is noted that many brick manufacturers are located within close proximity to their source raw materials. The relative abundance of clay material is also touted, indicating that brick manufacturing does not further deplete scarce resources. One could take issue with the fact that sand, which is used in some (not all) brick production, is not mentioned in this context. With the increasing focus on embodied energy and embodied carbon in building products, perhaps the BIA will update this Technical Note with data to assist with life cycle analysis studies.  

Technical Note 31 Brick Masonry Arches (January 1995) 
Note 31 is where we read about the methods and design details for constructing an arch, or more accurately, the various types of arches. (Apparently, there are many things, covered in Notes 1 though 30, that bricks want and need prior to getting to discussion of arches!) The brick note on arches is nothing less than a history and catalog of the arch, in its many forms, combined with a comprehensive discussion on arch construction and performance. Notes 31A, 31B, and 31C expand on and further delve into arch-related topics. Note 31A on the Structural Design of Brick Masonry Arches may also be quite helpful as you design your arch. Far more than simply providing details to be copied and pasted, Note 31 provides all of the rich terminology that describes each line and element of an arch. Of course, this includes terms that you probably recognize — centering, keystone, voussoir. But what about these — intrados, extrados, and skewback?  

The abundant detailing information is specific to brick arches but also at least somewhat applicable to other construction materials and scenarios, given a little imagination and critical thinking (despite the BIA’s disclaimer quoted earlier in this article). There is specific discussion of keystone size, placement, and configuration, as well as the different ways of detailing the skewback and abutment (where the arch bears on a wall or pier). Looking ahead to building maintenance, it is noted that: “With most arch types, the likely location of the first crack when the arch fails is at the mortar joint nearest to the midspan of the arch.” The comprehensive nature of the discussion — from history, to terminology, to aesthetic considerations, to construction detailing, to maintenance of the constructed building — mirrors the challenges of the design professions and provide unexpected reminders of the overall context of our work. 

Technical Note 48 Sustainability in Brick (November 2015) 
The last brick note in the series discusses sustainability and conveys the feeling that the BIA felt compelled, if not particularly inspired, to address the issue. The note goes into some detail on how brick can contribute to LEED Certification (in addition to addressing other topics). While much of this content is not particularly innovative, it does provide a reasonable summary. Not noted or discussed in the note is the presence (or not) of Environmental and Health Product Declarations (EPDs and HPDs) within the brick industry. This would be a useful addition to a future update on this technical note. 

The note offers a critique of green building rating systems, and their approach to materials, stating: 

However, what is often lacking in these rating systems is a means by which to promote and measure the avoidance of negative impacts. For example, efficient use of materials is not well recognized. Brick masonry elements that perform multiple functions avoid the use of other materials, such as paints, sound insulation, etc. Another limitation of these programs is inattention to durability. 

Durability of materials is sometimes difficult to estimate or quantify, but of course, materials (and buildings) that last longer are often more environmentally responsible. Durability of exterior wall systems is often determined by weakest link, and Note 48 provides helpful wall section and detailing recommendations to ensure the long-term performance of brick walls.  

Conclusion 
The “brick notes” belong to a dwindling set of printed resources once used by architects in the day-to-day practice of designing and detailing buildings. For me, that technical bookshelf included a SMACNA sheet metal manual, the book of steel design and steel shapes, multiple reference books by Francis D.K. Ching, and Architectural Graphic Standards. Of course, these resources are now available online in one form or another. As a genre, the “technical note” has survived the transition from print to digital. The best online example that I can offer would be the approximately monthly “Insights” published by Building Science Corporation (on buildingscience.com). The insights are generally very informative, and occasionally funny, examples of the genre.  

Originally printed pamphlets that were collected in a three-ring binder, all of the brick notes are now available online. A young (or older) architect considering or working through brick details could do much worse than to browse through the brick notes. I wonder, though, if a little something has been lost in the translation from a binder of paper pamphlets to an online cache. That four-inch-thick binder that I remember? We still have it, and the pamphlets appear to have been last updated in 2006. I haven’t looked at it in years, until I was preparing to write this article. While encouraging my colleagues to take advantage of the online brick notes, I might just spend some time myself paging through the hard copy pamphlets and looking for inspiration.  

Acknowledgement: While difficult for me to footnote any particular passage in this essay, I would like to credit Dan Willis from Penn State University, for his thinking and writing on brick, as one of the inspirations for this issue of CONTEXT. 

Todd Woodward, AIA is a Principal at SMP Architects, Lecturer at the University of Pennsylvania, and a member of the CONTEXT editorial board.