Bricks Made From Waste Fly Ash

Originial Article appeared here:

http://online.wsj.com/article/SB10001424052748704746304574506030258504644.html

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By CARI TUNA

Amid buzz about algae biofuel and electric cars, some start-ups hope to use "green" technology to reinvent more mundane products like bricks and cement.

CalStar Products Inc. plans to open a factory next month to make bricks from fly ash, a byproduct of coal burning. It claims to use roughly 85% less energy than traditional clay brick manufacturing, with an equivalent reduction in carbon-dioxide emissions.

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Cari Tuna for The Wall Street Journal

Workers at CalStar's Newark, Calif., facility press the fly ash into a test mold.

"Innovation is not necessarily discovering new things, but discovering how to use old things in a new way," says Amitabha Kumar, CalStar's director of research and development.

The process for making clay bricks—mining clay, forming it into bricks and firing in kilns using coal or natural gas—has remained largely unchanged for decades, though manufacturers have made improvements to reduce environmental impacts.

CalStar forms its bricks from fly ash—a gray, chalky byproduct of burning coal— and a proprietary stew of chemicals. During eight hours of steam baths, the calcium in the fly ash hardens, making bricks that look, feel and act like their clay counterparts, Mr. Kumar says.

CalStar says the bricks are designed to meet standards set by ASTM International, a standards-setting organization, for things like strength, durability and water absorption—and will be installed in buildings for the first time early next year. CalStar says the bricks will be priced competitively with commercial clay bricks. In Chicago, for instance, its bricks will sell for 53 cents apiece on average, compared with 55 cents on average per commercial clay brick, Calstar says.

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Cari Tuna for The Wall Street Journal

CalStar makes bricks using fly ash, a byproduct of coal burning.

Executives at the Brick Industry Association argue that CalStar's fly-ash products aren't bricks by definition, and question whether they'll last as long as clay bricks. "No one knows how the fly-ash unit will really perform," says Dick Jennison, the trade group's president.

Richard Klingner, a civil engineering professor at the University of Texas at Austin who sits on the ASTM's panel for brick standards, says the ASTM's standards don't apply to fly-ash bricks. That doesn't mean they are unsuitable for buildings, he says, "it just means that there isn't a standard for them yet."

The Environmental Protection Agency says fly ash is not hazardous and has advocated its reuse in building materials, though an EPA spokeswoman says the agency is reconsidering the classification this year. Most fly ash is mixed into concrete or disposed of in landfills.

CalStar's Caledonia, Wis., factory will recycle fly ash from a neighboring Wisconsin EnergyCorp. coal plant, making 40 million bricks annually and shipping only to nearby cities, to minimize carbon-dioxide emissions.

Cement maker Calera aims to capture carbon-dioxide emissions before they are released into the atmosphere. The start-up, is backed by nearly $50 million from Khosla Ventures.

In Moss Landing, Calif., Calera will pipe exhaust fumes from Dynegy Inc.'s natural-gas-burning power plant to its pilot facility, set to open this year, where it will flush the gas through seawater or brackish water. That will produce chalky substances it can use to make cement.

Producing one ton of traditional cement releases roughly one ton of carbon dioxide, says Calera founder Brent Constantz. But making one ton of Calera cement captures half a ton of the greenhouse gas. And like CalStar's bricks, Calera's cement is less expensive to produce than traditional cement, he says.

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Fly Ash bricks made by CalStar

Photo Source: http://calstarproducts.com/

Small Brick Structure, Vauxhall, London England

I don't have any other information about this, but its near Vauxhall (the stainless steel bus shelter/subway entrance in the background). I came across it on a walk from Battersea power station.

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Battersea Power Station, London England, 1930-1950

Loads more information and photos here: http://en.wikipedia.org/wiki/Battersea_Power_Station

Report for Berkeley Prize, Travel/Volunteering in England and Ireland

The Rebuilding of the Cotswold Canals, Gloucestershire, UK

(Note: I'll try and post bigger/better photos, but I might just put up individual entries in the coming weeks featuring the architecture discussed here)

This report was written for the travel fellowship I was granted by the Berkeley Prize for writing this paper about aspects of Canada's bricklaying history.

September 2009

As part of the Berkeley Prize travel proposal, I outlined a trip that would allow me to observe several themes related to brick masonry architecture. The intentions of the travel proposal were as follows; first, observe examples of historic brick buildings that have been adapted and reused for new purposes; second, learn about the traditional bricklaying practices that were used for these buildings' construction which results in their longevity; and third, look at mid-density residential building examples that are prevalent in Europe, but not so common in Canada. This lead me first to London to study the modifications to the Tate Modern building, next I headed to the Cotswalls for some volunteering where I learned how to lay bricks, and finally I ended up in Dublin where I studied how to respectfully insert modern buildings into an historic city fabric. Naturally, I learned just as much in unplanned observations as I did in those that I sought out, therefore I will discuss what I found most relevant and interesting during my travels.

Observations in London
In early August I arrived in London and made my way to Chelsea where I had arranged to stay for a few days. Exiting “The Tube” at the Baron’s Court stop, I found myself in a tightly knit three storey Victorian neighbourhood. The buildings were built of brick masonry and set back about 10 feet from the sidewalk to allow for basement entry and daylight to penetrate the lower windows. These smaller residential blocks of flats were planned and constructed together to create one continuous elevation of symmetrically mirrored units that surround the block and create an interior “courtyard” between the two sides of the block. Backsides of the flats allow for small outdoor courtyards for the main floor units, but more importantly they enable trees, small flower gardens and vined green space that can be observed from all of the upper floor units. Attached housing means shared walls between units which results in less material used for construction, and heat loss is reduced to two sides instead of a detached unit that has four sides. What I found most interesting about these residential blocks was the way each unit became uniquely defined by way of incremental changes. Over time certain units had painted or replaced front doors, had new mortar repointed in a different colour or style, planted vines, perhaps added a stained glass transom window or roof dormers to gain precious space, all small changes which ultimately combine to make street elevations of pleasing variety, but still harmonious from one unit to the next because of similar overall form and massing.

A notable difference between the European and North American concepts of architectural history is the approach to re-use versus restoration. The North American ideal tends to favor perfection where historic buildings are frequently “restored” to an artificial new museum like state. Most, if not all, evidence of human use and previous modifications to the building are erased and, in extreme cases, complete portions are re-built to keep the building 'consistent' with a certain era. The European approach to historic buildings includes a much more sensible practice of re-use. The idea that a structure has value in its age is acknowledged, and buildings are often stabilized structurally so that the ‘historic thread’ is demonstrated by the building’s patina, modifications, repairs and so forth.

The Tate Modern art gallery in London is a great example of the European approach to re-use. The building, originally designed by Giles Gilbert Scott as a power station, was re-invented as a modern art gallery by Herzog and deMeuron in 2000. Modern entrances were inserted where necessary at the ground level, and modifications were denoted by the use of red brick as a mild contrast to the original yellow brick which is toned grey/black from patina. These changes transformed an antiquated structure and have allowed it a new life where it has been seen and used by over 30 million visitors since reopening nine years ago. Future plans include a new addition on top of subterranean oil tanks which will add an additional 60% of space to the gallery. The proposed addition is to be completed in 2012.

Tate Modern, London

Not far down the Thames River from the Tate gallery is the OXO development. This project includes the dramatic modification of an existing building where the façade facing the river and a portion of the original building were left intact, and a new mixed-use building was created between the two structures. The new development includes exterior access to design shops and studios located on the first three floors with residential units on the upper floors, and adjacent space in the remaining portion of the original building. By leaving a space between the new and old buildings, an outdoor courtyard is achieved where ground floor restaurant patios and pedestrians walking along the river are free to use the space. A particularly interesting aspect of the new design exposes an old connection between previous buildings by the “ghosted” section left on the elevation. This sort of historic reveal is fascinating to see and its inclusion is a valuable contribution to the public because it demonstrates the original construction method and the fact that cities are continuously growing and changing.

OXO Development, London

Another site I visited in London was the Battersea Power Station, a handsome example of Victorian industrialization and also an integral component to providing power to London. It now sits vacant with steel hording installed to keep it from crumbling. Several proposals over the last ten years have been put forward for the re-use of the building and surrounding site, but the current economic recession has put a hold on the project and it remains uncertain what will ultimately happen with the building.

Battersea Power Station, London

These three examples of creative solutions to existing buildings allow for the re-use of building material where possible and enable the story of the building to remain, they demonstrate a vibrant alternative to a strict museum quality “restoration” that can be the unfortunate fate of many North American re-use projects.

Canal Restoration in the Cotswolds
After a few days in London I headed west in England towards where I planned to volunteer for a week working on a Cotswold canal restoration project. I took the train to Stroud where I was picked up by the camp directors and brought to the Scouting Hall where myself and the rest of the volunteers would be sleeping and eating for the week.

Let me back up for a minute and explain a few things; In England before trucking and trains became the common method of transportation, there existed an elaborate system of canals and rivers where long narrow boats were used to ship cargo around the country. For centuries this was the way that building materials, food, coal, and livestock were moved in England and it functioned very well. After the automobile became the main method of shipping some of the canals were filled in as a result of disuse. Today, many of the canals still exist and are primarily used by houseboats in an elaborate canal cruising sub-culture that really needs to be seen to be fully understood, but essentially some people live in, and other people vacation on long narrow boats that travel through the canals and dock at various quays. Its pretty wacky, but its also fascinating, especially the architecture of planning a 7' x 40' living space.

In order to keep the canals in working order a British organization called theCotswold Canals Trust exists that arranges weekly volunteer groups through the summer months to help keep the canals functioning and work towards re-instating several historic canals that have since been buried or fallen into disrepair. These canals run through many small villages in England and provide bike and walking paths in a charming setting where the public can stroll next to the river.

My time in Stroud was spent with a group of nineteen other volunteers who worked together on a site at Gough's Orchard. In order to join the canal systems to various rivers water locks were engineered and built to compensate for the change in elevation and allow boats to move uphill, the site at Gough's Orchard included one of these water locks. This particular location was infilled in the past and consequently the restoration first began this July with a dig-out of a fifty foot portion of the buried canal and lock chamber. Previous volunteer groups continued excavation work through July and erected scaffolding in early August. Our group arrived mid-August to a well prepared site where the restoration work began.

The water lock walls were constructed of 10 wythe deep brick walls laid in English bond which meant alternating courses of the long side (header) bricks and short side (stretcher) bricks. The mortar for the walls was originally a mix of lime, sand, fine aggregate, and water, which resulted in a soft mortar that allowed moisture to drain through the walls. This straight forward construction method allowed our group of untrained volunteers to learn the basic tasks and then work together to repair the walls as necessary.

Stroud Canal Restoration Site

The main jobs on the site were as follows:

Demolition - Observing the masonry walls to indicate lose, cracked, and rotten bricks that were "soft" from moisture absorption. A hammer tap test was also preformed to listen for unsound bricks. Once indicated, the bricks were removed mainly by using hammers and chisels, more difficult areas used small hand held jack-hammers to facilitate the process.

Brick sorting & cleaning - After bricks were removed from the wall they were sorted into re-useable and unusable piles. Even after more than one hundred years, many lose bricks were in good shape they simply needed to be re-set with new mortar in the wall; these bricks were cleaned using chisels and wire brushes to remove old mortar and then stacked to be re-set in the wall.

Mortar Mixing - Two people were needed to continuously mix mortar from a lime, sand, fine aggregate and water combination, and supply it by wheel-borough to the folks laying bricks in the walls.

Bricklaying - Under the guidance of two former 'brickies' (also volunteers), we were shown how to set bricks to a level line, how to lay a bed of mortar followed by a 'buttered' brick (prepared with mortar), and how to lay them flush with adjacent bricks. Once semi-dry, the final step was to remove excess mortar with a soft brush and finish the mortar joint profile with a tool.

Volunteers were given demonstrations for the various jobs on site. Each day tasks alternated depending on our own interests and the week-long goal of completing one side of the water lock.

In previous readings about brick masonry work, I learned that historic brick walls were often laid with lime mortar. This mortar mix allowed moisture to pass through from the interior of the wall to the exterior, and it dried softer than brick which meant that it would allow mild "give" as walls naturally shift and settle over time. I had also learned that it was poor practice to use cement mortar with historic brickwork because this type of mortar dries harder than old bricks and as the bricks move, expand, and contract with seasonal moisture they often crack and fail because the cement does not allow the "give" that lime mortar does. During the canal rebuilding project I was able to see firsthand and understand when and how to use these two types of mortars and the clear difference between the two. The canal walls had been repaired in the past with cement mortar in certain areas and it had caused many bricks to crack and crumble instead of shifting with the wall. As we worked to remove rotten bricks and repair the wall it was very evident where cement mortar had been used because it was nearly impossible to remove with a hammer and chisel and required large portions to be jack-hammered out and removed with crowbars. Very few of the bricks laid with cement mortar could be salvaged because of the damage caused during removal compared to those laid with lime mortar.

Restoring the brick masonry canal

The canal restoration was a week of satisfying outdoor work and learning. What I found most pleasing was talking with the local people as they passed by our construction site excited to see the canal being worked on. Many asked questions and several people returned to see the progress through the week and watch us build. As the week came to an end, we were able to realize our goal of rebuilding one side of the lock wall and preparing the other wall for the next group of volunteers.

Observations in Dublin
The last part of my trip involved traveling through Ireland to Dublin where I spent the remainder of my time studying the city's urban fabric and observing the placement of contemporary and historic brick buildings in this setting.

1. Timberyard Social Housing, Cork Street, Dublin 8.
An bold example of a well scaled modern residential building is the Timberyard Social Housing by O'Donnell + Tuomey Architects. The project has a variety of elevations that take cues from the varying conditions on each side of the site. On one side of the development is a significantly smaller two-storey attached residential neighbourhood, which is acknowledged by a stepping down in height towards these lower buildings. The opposite side of the site is presented with a four lane boulevard which allows for a taller, bolder elevation. This new development is well placed contextually and engages in a dialogue with the surrounding area, as landscaping and trees fill in, the building will become a real part of the neighbourhood.

Timberyard Social Housing, O’donnell + Tuomey Architects, Dublin

2. Historic Georgian Housing, St. Stephen's Green, Dublin.
Georgian Housing in Dublin was originally built for the wealthy, but many of the buildings were converted to tenement houses in the 19th century with the interiors divided into multiple living units. History aside, these buildings' uniformity in scale and horizontal alignment of windows provide an overall order and organization to form a continuous street elevation. Individual property divisions are indicated by changes in brick tone and colour, and from a pedestrian's point of view the variety in mortar shades, stone bases, doors, and iron details become a richly crafted architecture. These properties from the 18th and 19th centuries contain many good lessons about how to be a good neighbour in relation to the street and adjacent buildings.

Georgian Housing, Dublin

3. National Photographic Archives, Temple Bar, Dublin. O'Donnell + Tuomey Architects. (Post Script Note: I did not realize two of these buildings were by the same architects until I looked them up afterwards. Evidently, I appreciate their work) More important than the style of this building is the scale and material used in its construction. The surrounding Temple Bar area of Dublin consists of four to six storey buildings built primarily of red brick. This building was designed in conjunction with the lot behind to develop an outdoor market and gathering space where video projections can be shown. By matching the materials and scale of existing adjacent buildings the National Photographic Archives demonstrates a contextual sensitivity that allows the whimsical post-modern design and details to blend into the streetscape.

National Photographic Archives & Context photo, Dublin. O'Donnell + Tuomey Architects

Final Remarks
What made the largest impact on me during this trip is the notion of designing with contextual awareness. Historically, many areas in England and Ireland constructed buildings using similar materials as a default because those were the available resources at the time. Today we have many more options in terms of construction methods and materials that enable almost anything we can imagine. Studying the surrounding context to choose building materials and appropriate scale can develop and contribute a respectful architecture that acknowledges existing buildings and engages in a dialogue with the neighbourhood.


Bibliography:

Architect Jeffrey Scherer discusses "historical thread"
(http://www.metropolismag.com/story/20070518/a-stitch-in-time)

Additional Photos and Observations from my travels
(http://brickmasonry.blogspot.com/)

Further Information on UK Canals & Volunteering
(www.cotswoldcanals.com)