When performing historic foundation repairs, compliance involves meeting a combination of local, state, and national preservation standards. The primary requirements include:

• Professional Engineering and Inspection: Repairs must begin with a structural engineer foundation inspection. A licensed Professional Engineer must assess the structure and produce a sealed report, which serves as the blueprint for all repairs and ensures the project meets Colorado building codes.
• Preservation Mandates: Designs must comply with local preservation mandates (such as those in Denver and Douglas County) and follow National Park Service (NPS) preservation guidelines. These standards emphasize minimal intervention, prioritizing the repair of original materials over replacement to maintain historical character.
• Material Compatibility: Code and preservation standards require the use of compatible materials. For example, using modern high-strength mortar on historic stone can cause structural failure; instead, lime-based mortars or period-appropriate mixes should be used.
• Site-Specific Engineering: Structural stabilization, such as helical pier underpinning, must be based on a geotechnical report and site-specific soil analysis to ensure the repair method accounts for the load requirements and structural constraints of the historic building.
• Permitting: All restoration plans must confirm that necessary permits are obtained and that the proposed work adheres to established preservation guidelines before implementation.

• Historic Foundation Restoration: Colorado Homeowner’s Guide