When a client needs more space, the right answer is often expansion of an existing structure. Each expansion presents the structural engineer with a new set of challenges, and often the opportunity to innovate to achieve specific client goals. Walter P Moore has worked with owners and architects for over 80 years to expand every type of structure – many that were not originally design by our firm and many for which no credible structural documentation was available. In expanding these buildings, we have solved a myriad of challenges presented by unknown underground conditions, limited structural capacity in existing columns, lateral systems and foundations, ongoing occupancy and events during construction, and the need to match existing floor heights. When there are undocumented materials, we draw on the expertise of our diagnostics specialists to evaluate their strength and characteristics. And, we use the latest cloud technology to document the exact location of existing structural elements.
Foundation and column strengthening
The most fundamental concern in vertically expanding a structure is the capacity of the existing foundations and columns. Walter P Moore carefully analyzes the loading capacity of these crucial elements with the goal of avoiding strengthening if possible. Where strengthening cannot be avoided, we draw on a full array of structural solutions to increase the capacity of foundations, columns, and walls.
Vertical expansions of existing structures are often the right answer to add needed functional space. When vertical expansion has not been anticipated in the original design, Walter P Moore will carefully analyze the existing structural frame including options to minimize the cost of any required reinforcing or disruption of the existing operations. We develop structural expansion options that minimize the weight and cost of new construction impacts while providing the needed quality of new space.
Sequencing and phasing design
Proper phasing of vertical and horizontal building expansions is often crucial to minimize disruption to existing operations and minimize overall costs due to access and construction efficiency. Walter P Moore works with owners and builders to optimize expansion phasing, often using 4D modeling to clearly communicate phasing issues.
Evaluation of undocumented structures
When documentation of an existing structure is unavailable, incomplete or unreliable, Walter P Moore uses a variety of assessment techniques to rationally determine the capacity of the structure. These techniques include electronic and/or physical measurements of elements, visual and analytical assessment of materials, and sampling and laboratory testing of key materials. In most cases we are able to adequately ascertain the capacity of the structure to inform the desired improvements.