The following procedures are followed by Granite Foundation Repair during the installation of concrete pilings to assure that the customer receives the best possible foundation repair by driving the piling system as deep as possible.
Clay soil limits the installation depth of pressed concrete pilings. Pressed concrete pilings are carefully driven by Granite Foundation Repair to refusal. Refusal is defined as that depth at which the piling system encounters sufficient resistance to prevent the attainment of further depth. Resistance is caused both by the sides of the piling and the end. In Dallas, Coppell, Garland and surrounding DFW Metro areas, the refusal may be caused either by compressed clay, or rock/sandstone and typically occurs at depths of ten to twenty five feet. It is possible to attain refusal at depths as shallow as five feet, but this is not a recommended practice except unless refusal is caused by stone.
- Review locations of utility markings.
- Crew chief shall review general condition of structure, inside as well as outside.
- Identify pier locations per the pier diagram- some location adjustment may be necessary due to trees, plumbing, A/C, buried cables, etc.
- With the property owner, review pier placement in those areas with bushes, trees, garden plants, flowers and concrete breakouts. Concrete breakouts are necessary to install pilings in areas covered by sidewalks, driveways or patios.
- As needed, place protective ground cover (plastic or plywood).
- Identify locations for electrical and water hook-up to the house.
- Remove plants as needed for pier installation. Small plants and most bushes may not survive being transplanted.
- If concrete break-out is required for pier location, saw cut edges and jackhammer out the concrete.
- Dig top holes approximately 3’x 3’ to a depth of approximately 27” below the grade beam. Cut sprinkler lines as needed and later splice.
- Place pre-cast concrete cylinders under grade beam and use hydraulics to slowly drive the pilings to refusal. The grade beam should rise 1-2 inches to assure refusal. Use water as needed to facilitate increased drive depth. Driving adjacent piers at the same time is not recommended.
- Place trapezoidal block atop concrete cylinder piling, and hydraulic jack atop block.
- After all pilings are installed, lift house in pre-determined sections using hydraulic jacks. Lift as much as practical. Place 2 concrete cylinders cut to length atop block. Insert steel shims as needed. Requires one individual periodically inside house to monitor lift.
- Fill holes with soil, mounding to allow for future settlement. Splice sprinkler lines. Replace plants where practical.
- Patch concrete breakouts, touch up mortar and caulk in areas of pilings.
- When specified by contract, epoxy patch cracks in slab.
- Rake area and remove excess dirt.
- Final walk around property with customer to assure customer satisfaction.
Same process as exterior piers, with following additions:
- Customer should have furniture removed and carpet lifted for an area of 6 feet from any pier location. We recommend a carpet repair specialist, who can as well remove and replace furniture and re-seam. Pets must be removed.
- Customer shall have area cleared so that a worker with standard wheel barrel can transport dirt outside of the house.
- Pier location shall approximate drawing, and where practical the pier shall be located at a grade beam. When no beam is available, depending upon slab strength, metal reinforcement may need to be used under the slab. Typically that reinforcement is a 4”-6” I Beam, approximately 2 feet long.
- Floor shall be covered by Granite personnel with sufficient plastic and/or fiberboard (RAM BOARD) to create a walkway to outside, except in areas of bare concrete breakout.
- It may be necessary to put plastic on the walls to minimize dust accumulation. Advise customer that we can minimize, but cannot guarantee dust accumulation, which is the responsibility of the customer.
- Interior openings in occupied structures shall be covered overnight.
- Saw cutting can create a dust storm and is seldom used inside the structure.
- Remove plastic and sweep or vacuum as needed after pier installation and patching of the concrete.
- Final walk around the property to assure customer satisfaction.