Underpinning is the extension of the existing foundation down to competent bearing material, which is material that will support the weight of the house and foundation without settling. Techniques include installing reinforced concrete piers, driven steel piles or push piles, hand-dug pits, helical anchors or self-drilling anchors.
Underpinning helps stabilize the foundation, and is often necessary as first step to a major home remodel.

Underpinning is often an excellent solution to level floors, stop the foundation from moving, lift the home close to it’s orginal position, and greatly increase the value of your home.

RWR uses portable equipment during installation, with minimal disruption to your home and surrounding area.

Schedule a free inspection with one of our professional consultants, and get our recommendations for your situation.

Here is an example estimate from RWR, so you can get an idea of the detail and professionalism you can expect from our team of specialists.

This estimate based on plans, drainage plans and structural drawings. The bid is for the installation of a new reinforced concrete retaining wall as described below.

This price includes labor and materials to complete job as per the itemized scope of work listed below.

Scope of Work
Structural Sheet S1
• Mobilize to jobsite. Demobilize.
• Supervision.
• Perform weekly cleanup.
New Concrete Foundation Installation
• Excavate for and install new reinforced concrete foundation footings, grade beams; stem walls and garage structural slab as per structural details and layout on page S1. Includes exterior patios and concrete stairs. Rat proofing is not included in this price.
• Clean up site and remove RWR related construction debris.
Pier Installation Option #1 (14 ft. deep Piers)
• Drill and install (69) 16” diameter x a maximum of 14 ft. deep reinforced concrete piers, (60) as per structural detail 1/SD3 and (9) as per structural detail 3/SD3. Remove drilling spoils from site. (See attached casing installation and removal cost).
Additional cost for Metal casing Installation to Option #1 (14 ft. deep Piers).
• The installation of the reinforced concrete piers may require the installation of metal casing as per verbal conversations with Pete Sequeira and the descriptions of the findings based on the soils report by Salem-Howes Associates Geotechnical Consultants. Casing installation and removal price is estimated . (To be added to the drilling price provided). Price based on full lengths of casing recuperated and re-used.
Pier Installation Option #2 (18 ft. deep Piers)
• Drill and install (69) 16” diameter x a maximum of 18 ft. deep reinforced concrete piers, (60) as per structural detail 1/SD3 and (9) as per structural detail 3/SD3. Remove drilling spoils from site. (See attached casing installation and removal cost).

Additional cost for Metal casing Installation to Option #2 (18 ft. deep Piers).
• The installation of the reinforced concrete piers may require the installation of metal casing and the descriptions of the findings based on the soils. Casing installation and removal price is estimated. (To be added to the drilling price provided). Price based on full lengths of casing recuperated and re-used.

Drainage plan C1.0
• Excavate and install (1) trench drain as per plans.
• Excavate for and install a new SDR 35 tite line for new roof drains (RD) and downspouts (DS) as per sheet C1.0 layout. Outlet as per plans.
• Excavate for and install new SDR 35 perforated foundation drain lines along the outside perimeters of the new house foundation as per C1.0. Foundation drainage lines consist of a new SDR 35 perforated line surrounded in ¾ crushed rock wrapped in filter fabric pocket approximately 1 ft. deep x 1 ft. thick approx located along the bottom of the new perimeter concrete footings (estimated at 18” maximum depth from existing grades). Waterproofing or drainage board installation is not included in this price.
• Excavate for and install for new 4” and 6” diameter storm drain lines and connect to one of the new outlet locations as per plans.
• Excavate for and install (9) different types of DI’s and AD’s as per sheet C1.0 layout, including all SDR 35 4”and 6” diameter perforated and tite lines.
Un-reinforced Rat Proofing
• Install approx. 2400 square ft of 2” thick un-reinforced concrete rat proofing at all new crawl space areas of the new house as shown on C1.0.

Notes
• Access to property was not possible. A site visit is necessary prior to confirm bid inclusions and exclusions due to unknown site conditions. Estimate is based on plans and normal conditions.
• Metal casing is priced based as rental price and all casing is assumed to be 100% recuperated.
• Elevations and layout to be provided by General Contractor performing the remainder of the project.
• Structural Shoring must be installed to a minimum of 1.5 ft. below the new slabs and footings sub-grades prior to RWR commencing the job. (See Alternate price for both items presented above).
• All soft and hard demolition must be performed prior to RWR starting the excavation task.
Optional Installation of Helical Piers
• Upon approval of soils engineer and structural engineer install sixty nine (69) 2-7/8 x a maximum of 20 ft. deep vertical helical piers with a 12” x 12” helix head in10 ft extensions. See Notes below.
• Helix is to be driven into the ground using track equipment to a torque of 10,000 maximum. Final Depth to be determined by soils engineer.
• Includes standard new construction helical head.
• Additional cost per ft for helical piers
• Helical Piers are 2 7/8” (o.d.) galvanized pipe material
Qualifications and Clarifications
• In full compliance with Cal-OSHA rules, annual permits and regulations for the performance of this job.
• Job is bid as package unless agreement to otherwise.
• Includes one mobilization only.
• Prices are subject to adequate supply of rock, concrete, asphalt, PVC resins, PVC pipe, fittings at prices quoted at bid time and are good for 30 days.
• Proposal is based on working std 40 hours per week, 5 work days and mutually agreeable schedules.

Exclusions
• Cost of plans, permits, bonds, inspections and testing.
• Any work on utilities including buried pipes.
• Increased cost of drilling or excavation due to hard rock, tree roots, underground water or caving soils. (Hard rock drilling is defined as a penetration rate slower than 1 ft. in 5 minutes.) (Hard rock excavation is defined as material that cannot be excavated with a conventional backhoe or excavator bucket).
• Hard/soft demolition.
• Metal I-beams/metal work or any related not mentioned above.
• Provide or install of shrink/leveling grout.
• Any drainage work not mentioned above.
• Asphalt Flat work/sub base preparation or any other than mentioned above.
• Concrete retaining walls or any additional concrete work not shown or related to house foundation.
• Repair to landscaping or irrigation.
• Cost of surveying if needed.
• Excavation of hazardous materials, underground tanks, or materials unacceptable at dumps.