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Sharring experiences in urban infrastructure delivery.
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Reusing Historic Street Bricks

By: Tom Davis Category: Misc Urban Infrastructure, Placemaking, Sidewalk Features

One of our Cotswold projects anticipated removing many old street bricks. We found bricks in many streets but the street where they were to be saved for reuse was also where we were removing unused old railroad tracks and placing the new water, waste water and storm water lines. But, we did not find enough bricks to rebuild the planned two blocks of Commerce Street either side of Main Street.CIMG6936.JPG

Looking back on that disappointment I now believe that was a blessing. Not that it was a bad idea but that we did not have the contract requirements in place to recreate a pavement equal to what our forefathers built. We also did not have a consistent brick source. We did plan plan to install the old bricks on a concrete slab to support the heavier vehicles of today.

We did find enough bricks to create two parking lanes–one in each block. Unfortunately the bricks found were from various blocks apparently placed at different times and were not uniform and hence we did not achieve a smooth surface with minimum gaps.

What should the construction specifications have required? Based on my years of trying to support the designers when they emphatically proclaim that all contractors should foresee the intent of the design and anticipate that anything a bit unusual may require mind-reading to properly bid, I strongly recommend that the preface to the spec section clearly state that the old/historic bricks to be reclaimed–or that have already been reclaimed–do not meet today’s manufacturing tolarences and will require special care to achieve the uniform surface. What was missing from the construction contract requirements was clear language with measurable parameters to measure the adequacy of the contractor’s installation¬† so it looked like, rode like, and walked like what we see in the old photos and that is reasonable for today’s standards.

As you consider the QA part of the requirements keep in mind how bricks and pavers are typically installed: i.e. on a sand bed. The sand is distributed over the base and screeded or troweled into a flat surface to support the bricks. Then the bricks are placed edge to edge on that flat surface. If the old bricks are wider in one direction than the other you will have uneveneness. In some cases that variance in dimension is very small and not consistent. The thicker bricks can be pressed into the sand but then the bed must be releveled before the next brick is placed or it will be slighly higher. I am sure the designers are saying that is obvious and a “good” contractor would slow down the installation and have the workers carefully re-level the sand bed. There are a few contractors that will foresee the coming issues that the designer did not care to note and that contractor will spend the money to make it right. But most superintendant’s are cost driven and their end of the year bonus is dependent on the job’s profits. The designer, the inspector and the contractor¬† can fight it out but the work will suffer all because the intent was not presented in the specs.CIMG6934.JPG

The specs should include a tolarence for vertical unevenness. I do not have a recommendation for that measurement at this time. One such measurement that we are familiar with is the ADA vertical maximum raised edge in a pathway: i.e. approximatley 1/4-inch. But if a series of bricks vary up and down by 3/16″ you will have a very rough surface to drive across–much less walk over.

This walking surface issue is very important in crosswalks. At crosswalks you will also need to consider how to address the traffic manual required white Stop Bar and the crosswalk stripes. Believe me that paint and thermoplastic look bad and do not last when applied to historic bricks. Besides there seems to me something sacrilegious about such an application on the old bricks.

You can avoid the uneven issues by designing the crosswalks to be concrete or concrete unit pavers. Be sure to read the posts at this blog site about paver crosswalk issues.

A measurement of vertical unevenness could also work against you as you are measuring from one old brick to another–not likely hard, even surfaces.¬† Consider including in your bid documents historic photos of a street with brick pavers that is what you want and what will be part of the basis for determining the acceptability of the finished work. Ideally if it is a photo of the same street where the pavers were or will be reclaimed. In our case there are many photos of streets in the immediate area that could have been included and the bidder would have been warned of what was to be achieved and the foreman would know what the crew must create with the old bricks. Given the few bricks we found along the 12 blocks we rebuilt and the randomness between them we still could only have created the parking lanes you see here in these photos.

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