Historic Preservation Construction Rules in Colorado

Historic preservation construction in Colorado sits at the intersection of state and federal regulatory frameworks, local landmark ordinances, and specialized building standards that differ materially from conventional commercial or residential construction rules. This page covers the key regulatory bodies, permitting pathways, classification systems, and decision boundaries that govern construction, rehabilitation, and alteration work on historic properties across the state. Understanding these rules matters because noncompliance can void federal tax credit eligibility, trigger stop-work orders, and result in loss of landmark designation.

Definition and scope

Historic preservation construction refers to any ground-disturbing, structural, or exterior alteration work performed on a property that holds a recognized historic designation — whether at the federal, state, or local level. In Colorado, three distinct tiers of designation create overlapping but separate regulatory obligations:

1. National Register of Historic Places (NRHP) — administered federally by the National Park Service (NPS) under the National Historic Preservation Act of 1966 (NHPA). Listing on the NRHP does not by itself restrict private owner actions, but it triggers Section 106 review for any project involving federal permits, licenses, or funding.
2. State Register of Historic Properties — maintained by the Colorado State Historical Fund and the Colorado State Historic Preservation Office (SHPO). Properties listed here qualify for Colorado state income tax credits under the Colorado Historic Preservation Income Tax Credit program.
3. Local Landmark Designation — governed by individual municipal or county ordinances. Denver, Boulder, Fort Collins, Pueblo, and Colorado Springs each maintain independent historic landmark commissions with their own design review standards and permit workflows.

The Secretary of the Interior's Standards for the Treatment of Historic Properties (36 CFR Part 68) define four treatment categories: Preservation, Rehabilitation, Restoration, and Reconstruction. These are not interchangeable terms — each carries distinct technical expectations that determine what materials, methods, and alterations are permissible.

Scope and coverage limitations: This page addresses Colorado-specific preservation construction rules applicable to properties within the state. It does not cover tribal historic properties governed by the Native American Graves Protection and Repatriation Act (NAGPRA), nor does it address federal agency undertakings subject exclusively to Section 110 of the NHPA. Properties outside Colorado or under exclusive federal jurisdiction fall outside this scope.

How it works

The regulatory pathway for historic preservation construction in Colorado follows a structured sequence:

1. Determine designation tier. Identify whether the property appears on the NRHP, State Register, a local landmark list, or a combination. Designation tier determines which agencies have review authority.
2. Identify federal nexus. If the project involves federal funding, a federal permit, or a federal license, Section 106 of the NHPA requires the lead federal agency to consult with Colorado SHPO before any project affecting historic properties proceeds. SHPO has 30 days to respond to most Section 106 submissions.
3. Apply the Secretary of the Interior's Standards. All rehabilitation work seeking federal Historic Tax Credits (HTCs) — which provide a 20% credit on qualified rehabilitation expenditures under 26 U.S.C. § 47 — must satisfy these standards as reviewed by both SHPO and the NPS.
4. Submit local design review application. Locally designated landmarks typically require a Certificate of Appropriateness (COA) from the municipal historic preservation commission before any exterior alteration, addition, or demolition. COA requirements vary: Denver's Landmark Preservation Commission operates under Denver Revised Municipal Code Chapter 30.
5. Obtain building permits. After COA approval (where required), standard Colorado building permits apply. Municipalities may apply modified code compliance pathways under the International Existing Building Code (IEBC), which Colorado has adopted as part of its International Building Code framework.
6. Pass inspections. Construction work is subject to standard building inspections plus any preservation-specific reviews required by the local commission or SHPO.

Colorado SHPO operates within History Colorado, located in Denver, and serves as the state's primary liaison to the NPS for federal tax credit certifications.

Common scenarios

Rehabilitation for tax credit qualification. A developer acquiring a contributing building in a National Register Historic District undertakes interior and exterior renovation. The project must pass a three-part NPS certification: historic district/building certification, Part 2 (proposed work), and Part 3 (completed work). Failure to maintain historic character-defining features — original window profiles, masonry mortar composition, storefront configuration — typically results in NPS rejection of Part 2.

Local landmark alteration. A property owner in a Colorado municipality proposes adding a rooftop mechanical unit to a locally designated landmark. The historic commission evaluates the proposal against local design guidelines. If the addition is visible from a public right-of-way, the commission may require screening, setback, or material changes before issuing a COA. Work begun without a COA can result in fines and mandatory removal. For context on how Colorado building codes interact with these reviews, the IEBC Chapter 12 covers historic buildings specifically.

Asbestos and lead paint abatement in historic buildings. Pre-1978 buildings designated as historic frequently contain asbestos-containing materials and lead-based paint subject to Colorado Department of Public Health and Environment (CDPHE) regulations. Abatement methods must be coordinated with preservation requirements — full removal of historic plaster containing asbestos, for example, may conflict with Secretary of the Interior's Standards guidance to retain historic materials where feasible.

Section 106 triggered by CDOT projects. Colorado Department of Transportation infrastructure work intersecting historic properties initiates Section 106 consultation. CDOT construction projects affecting NRHP-eligible properties require an Area of Potential Effect (APE) determination and adverse effect finding before construction proceeds.

Decision boundaries

The primary decision fork in historic preservation construction is designation tier and federal nexus, because these factors determine regulatory authority and compliance requirements:

Rehabilitation vs. Restoration contrast. Rehabilitation (the most common treatment) permits compatible new uses and allows limited modern alterations, provided historic character is retained. Restoration, by contrast, requires returning a property to a specific historic period, removing later additions, and replicating lost features based on documentary evidence. Most commercial historic tax credit projects use the Rehabilitation standard; Restoration is typically reserved for museum properties and publicly funded preservation projects.

When the IEBC historic building pathway applies. Section 1201 of the International Existing Building Code provides an alternative compliance path for buildings designated as historic. Under this pathway, strict conformance with current energy codes or structural upgrade requirements may be modified by the Authority Having Jurisdiction (AHJ) when full compliance would threaten the building's historic character. This pathway requires a formal determination by the AHJ and is not automatic.

Demolition thresholds. Local landmark ordinances typically prohibit demolition of designated structures without a separate demolition review — a process distinct from standard demolition permits under Colorado construction permitting rules. Some municipalities impose a delay period of 6 to 12 months to allow alternatives to demolition to be explored before the permit is issued.

For contractors and developers navigating licensing obligations on historic projects, Colorado construction licensing requirements apply in full — preservation designation does not create exemptions from contractor licensing or bonding obligations outlined in Colorado contractor bond requirements.

References

• National Historic Preservation Act of 1966 (NHPA) — National Park Service
• Secretary of the Interior's Standards for the Treatment of Historic Properties (36 CFR Part 68) — National Park Service
• Federal Historic Tax Credits (26 U.S.C. § 47) — National Park Service
• Colorado State Historical Fund / Colorado SHPO — History Colorado
• International Existing Building Code (IEBC) — International Code Council
• Colorado Department of Public Health and Environment (CDPHE) — Asbestos Program — CDPHE
• National Register of Historic Places Program — National Park Service

Related resources on this site:

• Colorado Construction Directory: Purpose and Scope
• How to Use This Colorado Construction Resource
• Colorado Construction: Topic Context