At the end of a successful project, it's easy to assume perfect conditions existed throughout construction. As a rule, however, no construction project goes without complications.

Early challenges just below the ground surface can be disastrous to a project and may include proximity to neighbors, bad soil, undesirable water conditions (like a high water table) and other unforeseen excavation difficulties.

Any unforeseen problem must be addressed expeditiously and effectively (hopefully during the design process), so it doesn't threaten the immediate success of the project.

CASE STUDY: HOMEWOOD SUITES BY HILTON

At the Homewood Suites by Hilton, Salt Lake City-Downtown, the design team knew from the beginning it would need to address some excavation issues. The facility, which opened in 2006, was constructed on the edge of the city's downtown area. It had been conceived, designed and constructed as a downtown infill project, meaning it was to use ”reclaimed” urban land to help restore life and a sense of community to the city's waning core.

The urban location also meant the construction site would be enclosed by relatively immovable boundaries. Projects in less-developed areas sometimes have the option of temporary access to neighboring undeveloped spaces for construction work.

Homewood Suites' developers wanted to maximize available space by constructing a building with the largest footprint possible. Parking requirements were resolved with two levels of underground parking and a foundation excavation exceeding 30 feet, adjacent to a downtown street on the north side. A traditional sloped excavation would have required tearing out the entire street, but even if that had been possible from cost- and city-management standpoints, it was unacceptable to neighboring property owners. The conventional alternative — vertical excavation and shoring the entire 30-plus-foot excavation — was cost-prohibitive.

All parties wanted to forge ahead and the developers' design team and the city's engineering and facilities departments partnered to craft a workable option.

COMBINATION OF SLOPE AND SHORING

In order to produce a manageable schedule and excavation method, the city agreed to a layback of the upper portion of the excavation's slope, which required only two of four street lanes to be blocked off during construction. This allowed the excavated wall's vertical portion to consist of only its bottom 10 feet, which reduced the developers' required shoring cost to a manageable amount. The compromise also minimized accessibility inconveniences for neighboring property owners and automobile drivers, while allowing the project to move forward.

An additional benefit of the sloped excavation was as utilities were exposed, crews were able to support and retain them in existing form. In contrast, if the entire excavation had been vertical, those same utilities would have been replaced at additional cost.

By utilizing and empowering the design team, developers delivered a project with long-term benefits to all stakeholders: developers and investors; city and community leaders; downtown businesses and residents.

CASE STUDY: LODGE AT OSPREY MEADOWS

Another example of construction confined to a limited area-albeit a very different one-is Tamarack Resort's Lodge at Osprey Meadows, a jewel in Idaho's Payette River Mountains. This upscale four-season destination is known for the beauty of its natural and man-made features.

The Lodge at Osprey Meadows is a large Western mountain lodge with wood beams, native stone, hardwoods and hand-wrought iron inside hotel rooms, studios and condominiums overlooking spectacular outdoor views. Following the success of the Lodge, resort owners decided to add a second “stand-alone” wing adjacent to the original lodge three years after its completion.