Colorado’s Ultra Low NOx Law and Commercial Buildings

As published in the Colorado Real Estate Journal Property Management Quarterly

Article by Andrew Sams. Click here for full Property Management Quarterly.

What property managers need to know before the next furnace or water heater replacement

Colorado’s Ultra Low NOx emissions law (HB23-1161) took effect January 1 and is gaining attention across real estate sectors. While much of the early conversation has focused on housing, certain commercial properties may also be affected. The reason is simple: enforcement is based on the type of equipment being installed, not how a building is classified.

This is a statewide product standards law, not a building code. It regulates what new equipment can be sold, leased or installed, rather than imposing direct requirements on buildings themselves. Existing equipment does not need to be removed simply because of emissions standards. The trigger occurs only when systems are replaced, meaning the impact will emerge gradually through normal maintenance cycles.

Across Colorado, many smaller commercial properties, like medical offices, retail suites, mixed-use buildings and professional condos, rely on residential-style gas furnaces and water heaters. Because of that overlap, property managers may be the first to encounter how changing product standards influence maintenance planning, tenant coordination and capital budgeting.

What the regulation actually changes

The newColorado regulation limits nitrogen oxide emissions from certain new gas-fired furnaces and water heaters. The law establishes emissions thresholds tied to equipment categories, including:

●       Forced-air central furnaces generally below approximately 175,000 BTU input

●       Gas-fired water heaters up to roughly 2,000,000 BTU input

●       More restrictive limits are applied to smaller systems, particularly those under 75,000 BTU input

The law does not regulate buildings directly. Instead, it restricts the sale and installation of new products that do not meet performance standards. For managers accustomed to replacing like-for-like equipment, that shift may introduce more decision points at the time of failure, depending on inventory and compliance options available.

Alternative compliance options may include installing equipment that meets the most recent ENERGY STAR standards or transitioning to electric heat pump systems where feasible. Supply houses are also permitted to sell through existing inventory manufactured prior to the effective date, which means some properties may not experience noticeable changes until later in 2026, as older stock is depleted.

Why smaller commercial properties require closer attention

Large engineered mechanical systems, such as boilers or certain rooftop units, may fall outside the scope of this specific regulation. However, smaller commercial buildings often use equipment that mirrors residential installations. Many neighborhood retail spaces and professional office condos rely on standard forced-air furnaces and tank-style water heaters.

When these systems reach the end of their service life, managers may encounter longer lead times, different venting requirements or shifts in installation approach compared to past replacements. Understanding which properties rely on residential-grade HVAC or water-heating systems allows managers to prepare well before an emergency occurs.

Maintenance planning and lifecycle awareness

From a property management perspective, the most practical takeaway is maintaining clear visibility into mechanical systems. Tracking installation dates, service history and expected lifespan helps shift decision-making from reactive replacement to proactive planning.

Pro Tip: Start documenting equipment age and planning for compliant replacements in upcoming budgets. For portfolios with aging residential-grade HVAC equipment, this law may increase capital expenditure expectations due to evolving product standards and installation requirements.

During routine walks or inspection reviews, consider documenting:

●       Equipment type, size and fuel source

●       Approximate age and remaining service life

●       Venting configurations and mechanical room access

●       Any tenant improvements that may have altered the original layouts

This information supports more predictable reserve planning and reduces last-minute decisions during peak heating or hot water demand.

Budgeting, tenant coordination and operational planning

Mechanical failures rarely occur at convenient times, and property managers often balance regulatory awareness with operational continuity. If a system fails mid-lease, replacement planning may involve temporary heating or hot water solutions, tenant coordination and revised project timelines.

Proactive conversations with ownership groups can help align expectations before an emergency arises. Reviewing potential replacement pathways with licensed mechanical contractors in advance may clarify whether future installations will remain gas-based, transition to ENERGY STAR-compliant equipment, or shift to electric heat pump solutions.

Clear communication with tenants becomes even more important when equipment standards evolve. Managers who understand how regulations influence equipment availability are better positioned to reduce uncertainty and maintain trust during maintenance projects.

Portfolio strategy and due diligence

For managers overseeing multiple assets, the Ultra Low NOx regulation presents an opportunity to evaluate portfolios through a mechanical systems lens. Identifying properties that rely on furnaces under approximately 175,000 BTU input or water heaters within the covered thresholds can help prioritize future upgrades and align capital planning across sites.

Inspection reports and mechanical assessments provide valuable insight during acquisitions, lease transitions and long-term planning. Rather than viewing regulatory change as a disruption, many property teams are using it to strengthen lifecycle forecasting and asset strategy.

A planning conversation rather than a compliance alarm

Much of the discussion surrounding the Ultra Low NOx law has been shaped by broad headlines that imply sweeping changes across all buildings. In practice, the impact is more nuanced. Because this is a product standards law governing what new equipment can be sold or installed statewide, most commercial properties will experience change gradually as aging systems are replaced.

Property managers who maintain strong visibility into mechanical systems and replacement timelines will be better positioned to manage risk, coordinate tenant expectations and protect long term asset value. In many cases, the Ultra Low NOx conversation is less about immediate compliance and more about informed planning for the next equipment replacement cycle.