Pre-Construction surveys and related monitoring services are vital components of risk management and damage prevention plans on any construction site. When construction activities are being conducted in urban areas and locations such as designated historic districts, surveys and monitoring programs are often required in order to comply with building codes that serve to protect adjacent structures. However, surveys and monitoring can also protect the interests of stakeholders involved.
Programs to monitor adjacent buildings begin prior to the start of construction activities. Construction activities which typically can have greater a impact or risk of damage on adjacent or surrounding buildings include foundation work, drilling, excavation, blasting and demolition. Building codes typically require that surveys and monitoring be conducted before and throughout the duration of certain construction projects, depending on a variety of other factors, including site location. In New York City, for example, when the construction activity is being conducted within 90 feet of a designated historic structure, preconstruction surveys and a monitoring program is mandatory for all adjacent structures in a radius of 90 feet.
Existing Conditions Documentation, or the Pre-Construction Survey is one precautionary measure that can mitigate potential risks involved prior to the start of any construction activity. It also serves to document any existing damage prior to the start of construction activities. This comprehensive survey involves a visual and photographic inspection of adjacent structures or properties, as well as extensive documentation. In order for a site to be fully compliant, a fully licensed technician is required to complete the mandatory existing conditions documentation.
The pre-construction survey will also determine where telltales and Crack Gauges may be required on the adjacent structures. Vibration Monitoring may be either recommended or required, depending on the type of property involved, or whether the site is within 90 feet of a designated landmark.
These measures not only mitigate risk on the structure, but may also protect interests of various parties involved, including the property owner, developers, contractors and others conducting the construction, as well as the owners/landlords involved with the adjacent structures. In specific building codes such as Technical Policy and Procedure Notice 10/88 in New York City, existing conditions documentation and monitoring programs are required specifically to landmarked buildings because they are particularly susceptible to damage.