Date: April, 2011
Location: Cleveland, OH
Contractor: Expert Basement Repair (EBR)
Engineer: Joe Nyzen, PE
Luxury homes are not immune to poor construction standards and methods or the hydrostatic pressures of the earth and surrounding soil.
A 10 year old luxury home in the greater Cleveland area had suffered foundation distress due to poor construction methods and hydrostatic soil pressure on the basement walls. Shifting and movement of the 9' high 12" concrete block walls caused the basement walls to crack. After a thorough review by a Professional Structural Engineer a repair plan was designed to correct the damage and stabilize the foundation.
Several problems had to be considered in order to effect repairs. One issue was the overburden load on the perimeter walls. The backyard elevation was nearly as high as the top of the basement foundation wall. A swimming pool and patio was already in place, consequently the grading could not be lowered with excavation not an option. Another concern was the removal of large areas of the floor in order to install all new deeper support pillar footings and stabilize a large stairway into the basement. Removal of floor sections to install deeper support pillar footings would possibly cause the perimeter footing to shift or fail.
The perimeter walls needed to be stabilized before any other repairs could be started. Design specifications called for 93 Fortress Carbon Kevlar grid straps 9' high installed from floor to ceiling at spacing varying from 2'0"-3'4" on center. 75 locations at the bottom of the block were also to be grouted at spacing varying between 2'0"-5'0" on center for shear protection. A section of wall beside a stairway would require 6 helical wall anchors be installed to prevent the wall from shifting at the bottom once that floor section was removed.
EBR elected to install the perimeter grouting first due to occasional overlapping of carbon fiber and grout locations. With the grout locations installed, capped off flush and cured, carbon fiber could be installed without having to adjust carbon fiber locations which overlapped grouted locations. After the carbon fiber installation had been completed the helical wall anchors were installed. With the Fortress carbon fiber and grouting installed the wall anchors will no longer be a critical stabilization element once the floor is repoured.
Fortress Carbon / Kevlar grid straps along with core grouting was chosen not only for extremely high strength but these methods of stabilization leave the face of the block wall virtually flat and requires no maintenance for future basement finishing. A lifetime transferable warranty will be issued to the homeowner by EBR on completion.