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SUMMER 2006 NEWSLETTER $2 Million Waterproofing & Concrete Restoration Project Adds Value for Owner & Tenants Parking garage waterproofing and concrete ENGINEER’S REPORT restoration isn’t the most glamorous type of DETAILS DETERIORATION construction project, but key improvements can greatly impact the usability and safety of a A well-known Fortune 100 company in facility. That in mind, waterproofing and concrete Houston has been experiencing the effects restoration can do more than bring a facility up of two deteriorating parking garages on their to structural standard; it can also serve the campus near the Galleria. As happens to most functional needs of owners and their tenants. parking structures over time, parts of the concrete and steel decking, as well as the walls, Due to their utilitarian nature, parking structures began deteriorating due to rust forming on parts are sometimes ignored, yet they can pose a of the steel within. Given the nature of the unique set of expensive repair problems if not problems, a structural engineering firm was maintained properly. brought in to evaluate Heavy automobile the overall condition traffic wears out the After of the garages. The concrete surfaces and engineer’s report deteriorates the joints found several areas that are designed to of the concrete drive provide both parking and surface along with waterproof protection to the underlying steel the occupants of the decking in critical garage. The heavy load need of repair. imposed by a large The report also number of parked detailed other vehicles, wet weather, Before issues related to hot temperatures and the waterproofing extreme cold can further of the concrete Parking deck before and after waterproof traffic coating was applied. damage a garage components that INSIDE structure. The parking garage’s concrete, steel needed to be addressed to ensure structural this issue decking and expansion joints, therefore, must be integrity and to help prevent further deterioration adequately maintained. If neglected, the short- and of the structure. long-term effects of deferred maintenance can be very costly. ( Continued pg. 2...see GARAGE RESTORATION) Waterproofing & Concrete Restoration........................2 Back to Basics.............3 & 5 CONSULTANT’S Back To Basics: Factors to Consider When Designing a Building Envelope Preparing for Severe CORNER: Of the many factors that must be considered in the design of a Weather ............................4 building envelope, there are a few basic truths of science with which architects, engineers and contractors must deal. When Safety Program ignored, these cause the most problems with waterproofing. Recognized ........................5 A building envelope is comprised of the walls, roof and floor foundation (including below-grade walls and slabs-on-grade). By Claire McIntyre, AIA Projects in Progress............6 McIntyre & McIntyre, Inc. Different exposure factors for each of these lead to different ( Continued pg. 3...see BACK TO BASICS) WWW.CHAMBERLINLTD.COM ( GARAGE RESTORATION Continued from pg. 1 ) PHASE III BEGINS Before Sr. Project Manager Todd Eads with The original plan was to color code each Jones Lang LaSalle, led the building parking level by painting one wall on infrastructure reinvestment, which, in each floor a different color, but after the addition to the garage restoration, building owners saw the vast improvement included a complete air handling and that the color made, they chose to have HVAC renovation, elevator upgrades and all remaining walls in the garage painted various external repairs. “The garages white to provide a lighter, more were the single biggest portion of the secure environment. campus improvement project at over three million dollars,” said Eads who When construction was completed in hired Turner Construction as the general December of 2005 on Garage A, the contractor for the rehabilitation project. building owners were pleased with their beautifully restored parking garage and Chamberlin has completed many wanted Garage B to be equally as secure successful projects with Turner over for their employees, protected from the the years including The Calpine Center, After elements and structurally sound. “The vote Hilton Americas Convention Center Hotel was unanimous to utilize the Turner and and the Galleria Expansion project. Chamberlin team on Garage B,” said Because of Chamberlin’s proven track Eads. “We learned some valuable lessons record and wide range of waterproofing on Garage A and it was important for us to services, Turner entrusted the firm to be apply that knowledge to the second garage the single source contractor for the with a team that understood the project entire garage restoration project, with and our expectations from the beginning.” the exception of the electrical work. SECURE AND CONCRETE AND STRUCTURALLY SOUND STEEL DECK REPLACEMENT Garage B is an exact replica of Garage A Work commenced on Phase I of with very similar problems, so Turner and Garage A in November of 2004. Chamberlin knew exactly what to expect. Chamberlin began by removing and Steel deck before and after waterproofing and restoration. Restoration on Garage B began in March replacing deteriorated areas of the 2006 and is anticipated to be complete concrete and steel deck on five levels several weeks ahead of schedule in and patched portions of the concrete October of 2006. Upon completion, walls that were crumbling. All cracks in Chamberlin will have performed over the concrete that were less severe were $2.3 million of waterproofing and concrete strengthened with epoxy injections. restoration on both garages. “Our Metal doors and frames were replaced success on this project is due to our as well as sections of the metal deck wide range of waterproofing services, and various other steel components. experience and teamwork from everyone involved,” said Shane Hubbard, Phase II included pressure washing Chamberlin Senior Project Manager. all surfaces, vehicular traffic coating, striping parking spaces, caulking the Chamberlin is a single source provider entire garage and installing a new of complete garage restoration services. perimeter cable barrier system to Technically speaking, we provide the comply with revised building code expertise and attention to detail necessary restrictions. Chamberlin crews also to complete restoration projects up coated the steel joists attached to the to the highest standards. On a more underside of the deck to protect it from personal level, we’re proud that offering further oxidation. Upon completion, they this service contributes to creating a moved on to Phase III of the project: safer, more friendly structure for those interior concrete wall painting. Applying vehicular traffic coating to parking deck. that use the garage. HOUSTON 2 ACTIVE MEMBERS OF: AMERICAN SUBCONTRACTORS ASSOCIATION ( BACK TO BASICS Continued from pg. 1) designs and materials being selected Materials expand and contract with to waterproof each separate area. changes in temperature. Some materials are more stable than BASIC TRUTHS OF SCIENCE others, however. These differentials in temperature movements can stress In order to create a weatherproof the skins of walls and roofs resulting building envelope, the design in small microscopic cracks or large professional and contractor must not openings. Even small cracks in forget the fundamental laws of physics masonry or plaster walls will allow and thermodynamics. No matter what water intrusion from capillary action or new materials are developed, there rain being blown directly into the wall. are some basic truths that have always been and always will be Allowances must be made for these actions that must be accommodated factors to design and construct an in building envelope design and exterior veneer wall that will function Graphic A illustrates some basic truths of science. construction. Some of them are properly. Graphic A (at right) illustrates Source: National Institute of Building Sciences Whole Building as follows: these truths. Design Guide Web site article by Daniel J. Lemieux, AIA and Paul E. Totten, PE, Wiss, Janney, Elstner, Associates Inc. Water will seek the lowest level. If it DOUBLE INDEMNITY http://www.wbdg.org/design/env_wall.php happens to “bottom out” at a window or door head or sill or at the base of Okay, so we’ve established that water a wall cavity, then it must be directed will get through the exterior veneer and back to the exterior before it can into the wall cavity, whether due to come in contact with the interior movement cracks, blowing wind and wall components. capillary action or construction error. Now what? The answer is to provide a Wind creates differential pressures. secondary weather resistant barrier as These pressures can drive rain a drainage plane to the flashing that through a seemingly waterproof directs water back out. exterior wall and into a building interior. Air travels from high pressure to low The exterior veneer is the first line of pressure, and that pressure can drive defense for walls. It should not be quite a lot of water through very small relied upon as the only protection cracks in an exterior veneer. from the elements. Photo 1 (at right) illustrates what not to do. In the “old Air molecules move from warm to cold. days” this secondary wall membrane Photo 1: Construction Don’t! No Secondary Warm air holds more moisture than was often building paper (asphalt weather barrier and open joints in sheathing are an open invitation for water damage. Notice the lack of cold. Condensation forms when warm, impregnated sheets) lapped shingle flashing at the base of EIFS and the top of the stone. moist air is cooled to the dew point style to shed water. New products And look at all that mortar in the cavity space! (the temperature at which the air and code regulations have made the This building leaked like a sieve. cannot hold the water molecules). selection process more complicated. The dew point temperature is dependent on the relative humidity Once in the cavity space, water can of the air. Areas of low humidity will come in contact with the sheathing have a lower dew point temperature layer (the outside face of the wall than areas of high humidity.