Mr. Garner, a licensed professional
engineer with bachelors and masters degrees in civil engineering
talked to an audience of 35 about the investigation of existing
building foundations on high plasticity soils in order to determine
the cause of foundation movement.
of Mr. Garner's PowerPoint presentation:
of existing documents such as architectural and structural foundation
design plans and geotechnical reports should be conducted.
timeline of pertinent events should be written.
A site investigation
should be performed, including onsite interviews, photographs,
a visual condition survey of the foundation and superstructure,
spot elevation measurements of the foundation, leak testing of
the domestic water supply lines and the drain piping system, and
geotechnical borings under and around the building. For the spot
elevation measurements, Mr. Garner recommended foundation elevations
every 5 feet and outside grade elevations every 20 ft.
analysis of the existing documents, in combination with the field
data, should be performed to correlate observed distress, foundation
elevations, and sources of moisture and/or drying. Mr. Garner
emphasized that all data retrieved must correlate before the cause
of movement can be assessed.
is a proponent of cutting sections through the foundation and site
plan, showing exaggerated elevations in order to correlate apparent
vertical movement with such conditions as plumbing leaks and poor
outside drainage conditions.
said his firm, Carrasquillo Associations sometimes does not accept
a forensic project if the client is not prepared to spend the money
for sufficient testing needed to determine the cause of foundation