Installing foundation bolting for a residential seismic retrofit involves creating a continuous load path that prevents your home from sliding off its foundation during an earthquake. As a family-owned and operated team serving the Denver area since 1996, we follow a precise process to ensure structural integrity:

1. Professional Assessment: Before any physical work begins, you must obtain a structural engineer’s inspection and report. This forensic evaluation identifies settlement issues, wood rot, or soil conditions that might require additional measures like Helical Piers to reach stable strata.
2. Mudsill Bolting: We install bolts through the wooden sill plate directly into the concrete foundation. Following FEMA guidelines, we typically locate bolts within 12 inches of each end and every 6 feet on center. We drill holes at least 7 inches deep, clean them thoroughly, and insert anchors—using expansion anchors for solid concrete or epoxy anchors for cracked sections—then torque them to 50–80 ft-lbs.
3. Cripple Wall Bracing: For homes with short wood-framed walls between the foundation and the first floor, we install plywood panels to prevent lateral collapse. These are cut to size and secured with 8d common nails spaced at 4 inches on the edges.
4. Moisture Protection: To prevent long-term corrosion of the hardware, we recommend installing a Moisture / Vapor Barrier (6-mil polyethylene) over the crawlspace floor and sealing all bolt penetrations with closed-cell foam.

Because every home in Colorado has unique soil and structural needs, we recommend a custom on-site inspection to provide a tailored quote for your project.

• Seismic Retrofit Foundation Bolting: Complete Colorado Home Guide