811 Louisiana, formerly known as Two Shell Plaza, is a 26 story class A office building in Houston’s Central Business District. Camarata Masonry Systems, Ltd. (CMS) was contracted to help bring the forty-four year old building back to Class A standards and give it a modern aesthetic.
The renovation included removal of 1,800 pieces of the original travertine exterior cladding on the lower four floors and replacing it with 3,000 pieces of Virginia Mist Granite. The Virginia Mist Granite was supplied in three different finishes, honed, GEM8 and polished, to provide textural interest. CMS replaced the exterior sidewalk with 1,800 Brandy Crag Silver slate pavers in a flamed finish and replaced the interior lobby flooring with 3,555 pieces of Brandy Crag Silver and Concordia Schist in a honed finish. The Concordia Schist was used in the lobby area to accentuate the area around the security desk. The honed flooring created a path to the desk and polished Concordia Schist was installed on the wall directly behind the security desk creating a dramatic reflective surface. The three sizes of Schist pavers continued up the wall to further tie in the space. CMS also furnished and installed Aquasol Quartzite on the balance of the interior stone walls throughout the lobby. This material was book matched and end matched in the seating area of the lobby creating a unique natural work of art.
There were many special requirements on the project. First and foremost was the mandate that all of the stonework be completed after hours since the building was occupied. This involved the extensive use of task lighting which was necessary for safely demolishing, unloading, distributing and installing the stone. Fine stonework requires excellent visibility and is not easily performed by task lighting. Then, was the necessity to keep the sidewalks open and functional for safe pedestrian use throughout the work. This required the demolition and installation to be divided into two halves parallel to the street. The next requirement was the to keep the stone lippage to an absolute minimum since the design called for very powerful LED down lighting directly above the stone wall. The design also required mechanical stone anchors, a running bond joint pattern and long narrow stones. All of these elements enhance the possibility of stone to stone surface plane variance. CMS checked every stone to stone joint to ensure that the lippage was less than 1/16” and, in most instances, less than 1/32”. In many cases the stones had to be humored since they were warped but within allowable tolerances. Another requirement was the need for just in time deliveries. Normally, this is not possible with a project of this size and scope but CMS was limited to a modest amount of space in the garage which primarily accommodated tools and supplies. Most of the stone was stored offsite and delivered, unloaded and distributed at night on a just in time basis.
CMS faced quite a few challenges in addition to the special requirements mentioned above. One challenge was that the narrow strip windows had narrow strips of stone in between them thus requiring exceptional layout and installation accuracy. This was compounded by the fact that the mullions abutting the stone are plate steel with minimal joints. Another challenge was that all of the stone was erected on miscellaneous steel backup. Given the running bond joint pattern, extensive coordination was required to ensure proper steel member placement. An item requiring extensive time and coordination was the location of the structure which was covered by the original skin and pavers. True field conditions could not be determined until they were removed. Once removed, the building required the modification of wall heights and paver setting bed thicknesses. Some of these required very quick engineering, fabrication and supply solutions. Another challenge that required special planning was the installation of the 6’ x 6’ spandrel pieces. These pieces were installed 13’ above grade and weighed over 600 pounds. Because of their location, there was very little room to maneuver the stones with conventional equipment and CMS designed a special jig that would cradle the stones while they were being fit into position. The interior stone installation required extreme care not to damage or break any of the book matched and end matched stones as they were irreplaceable. Also, the Concordia Schist and Aquasol Quartzite walls contained stainless steel strips which appeared in a seemingly random fashion throughout the installation. Finally, the paramount issue was to preserve the safety of the building occupants and the automotive and pedestrian traffic. Throughout the eighteen month construction process, there were no incidents.
Through careful planning, extensive coordination between CMS, the Contractor and other trades, along with some outside the box thinking, Camarata successfully addressed all of the requirements and challenges on the job. The result was a successful update of a classic Houston building utilizing a range of unusual stones in an eye catching design.