DENVER GBOMeet the Green Buildings Ordinance with solar that pays you back
Green Buildings Ordinance Compliance. Denver.
Replacing a roof or building 25,000 square feet or more in Denver means meeting the Green Buildings Ordinance. Most compliance options are pure cost. Rooftop solar meets the requirement and then lowers your operating costs for decades. We size it to the smallest compliant system and capture every credit and incentive available in your area.
Get a GBO Compliance ReviewDoes it apply to you?
Who the Green Buildings Ordinance covers
Every covered project must install a cool roof and choose one compliance option. Single-family homes, duplexes, and certain townhome-style buildings are excluded.
Existing buildings replacing a roof
Buildings with 25,000 square feet or more of gross floor area that replace or re-cover more than 5 percent of the roof or a roof section.
New buildings
New construction with 25,000 square feet or more of gross floor area.
Building additions
Additions of 25,000 square feet or more to an existing building.
Your options
Compare the compliance options
Each path satisfies the ordinance. Only one keeps paying you back after the inspection is signed off.
On-site solar
Install rooftop or on-site solar sized to the city's coverage rules. It produces electricity that offsets your utility costs for decades and counts toward Energize Denver.
Green roof or green space
Vegetated roof or new at-grade green space. Adds structural, irrigation, and ongoing maintenance requirements.
Green Building Fund payment
A one-time payment calculated by the city at permit time. Simple, but it is a cost with no return.
Energy Program
Enroll and hit an energy use intensity improvement target within about five years, alone or paired with renewables.
Off-site renewables
Contract for renewable electricity covering 100 percent of building use, with a minimum five-year term kept for the program length.
Green certification
LEED Silver or higher, Enterprise Green Communities, NGBS Silver, or an approved equivalent.
Minimal cost. Real ROI.
Size to the smallest compliant system
The rules offer more than one way to size solar. We calculate each pathway for your building and design to the one that meets the requirement at the lowest cost.
Turn a requirement into an asset
Instead of a fee or a green roof to maintain, you own a system that lowers energy costs and we help you capture every credit and incentive available in your area.
Install once, on the new roof
We coordinate with your roofer so panels go onto the new roof within the city's 12-month window, without tearing anything up later.
Get credit toward Energize Denver
Under the city's April 2025 updates, renewables owned within Denver count at a 1.5x credit multiplier toward Energize Denver requirements.
The solar option, by the numbers
How much solar the GBO requires
A summary of the on-site solar rules in Denver's GBO Rules and Regulations. We confirm the exact requirement for your building during the compliance review.
Existing building, full roof
Panels covering 5 percent of gross floor area, 42 percent of total roof area, or enough to supply 100 percent of annual electricity use.
Existing building, one roof section
The requirement is prorated to the section being replaced: 42 percent of that section, or the floor-area share for it.
New buildings
Panels covering 70 percent of total roof area, or enough to supply 100 percent of estimated annual electricity use.
12 months to install
Existing buildings have 12 months from final roof inspection. Miss it and the building is enrolled in the Energy Program.
Panel and plan requirements
Panels rated at least 18 percent efficient, plus a roof plan showing panel areas, access, and clearances.
Flexibility for tight roofs
Provide at least 75 percent of the required coverage and pay into the Green Building Fund for up to the remaining 25 percent.
Summarized from the City and County of Denver's Green Buildings Ordinance guidance and GBO Rules and Regulations. Requirements can change, so confirm current rules with Denver Community Planning and Development before you file.
How it works
GBO compliance, handled end to end
We work alongside your roofer and project team so solar compliance never holds up your permit or your schedule.
Compliance review
We confirm whether the GBO applies, review your roof, floor area, and electricity use, and compare each solar sizing pathway.
Design & roof plan
We engineer the system and prepare the roof plan, panel specifications, and capacity details the city asks for.
Permitting & install
We coordinate with your roofer, handle permitting and interconnection, and install within the city's timeline.
Power on & savings
We commission the system, set up monitoring, and support it as it lowers your operating costs year after year.
Add storage for steadier power and lower demand
The same rooftop array that satisfies the GBO can charge a commercial battery system. Storage trims peak demand on many commercial rate plans and keeps critical equipment running through outages.
- Battery storage and UPS that integrate with solar
- Peak demand reduction on eligible rate plans
- Backup for the loads that cannot go down
Pair your GBO roof with the federal solar credit before it ends
Solar installed on a GBO roof replacement can also earn the federal clean electricity investment credit, but only if the system is completed and powered on by December 31, 2027. The credit starts at 30% of eligible project cost, and bonus adders of 10% each can push it higher. Roof replacements, permitting, and utility interconnection all take time, so plan the solar with the roof.
Base federal credit
Domestic content bonus
Energy community bonus
Low-income community bonus
Battery storage is not part of the 2027 cutoff. Storage keeps the full credit for projects that begin construction by December 31, 2033, then steps down to 75% in 2034 and 50% in 2035.
Bonus adders depend on project location, equipment, and eligibility, and the low-income bonus also requires an allocation. Systems 1 MW AC and larger must meet prevailing wage and apprenticeship rules for the 30% rate, and equipment sourcing rules apply. Confirm your credit with a tax advisor.
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Green Buildings Ordinance questions, answered
Understanding the GBO
What is the Denver Green Buildings Ordinance?
Denver's Green Buildings Ordinance (GBO) took effect November 2, 2018. It applies to new buildings 25,000 square feet or larger, building additions 25,000 square feet or larger, and roof permits for existing buildings 25,000 square feet or larger. Covered projects must install a cool roof and choose a compliance option such as green space, on-site solar, off-site renewables, the Energy Program, a green building certification, or a payment to the Green Building Fund.
Does replacing my roof trigger the Green Buildings Ordinance?
For existing buildings with 25,000 square feet or more of gross floor area, yes. According to the city's GBO rules, a roof replacement or roof recover covering more than 5 percent of the total roof area or of an individual roof section triggers the cool roof requirement and a compliance option. Single-family homes, duplexes, and certain townhome-style buildings are excluded.
Is the GBO the same as Energize Denver?
No. Energize Denver sets annual benchmarking and energy performance requirements for buildings 25,000 square feet and larger, with the city's April 2025 updates moving deadlines to 2028 and 2032. The GBO is triggered by a construction or roof permit. The two connect through the GBO Energy Program option, and the city expects most buildings on track for their Energize Denver targets to meet Energy Program requirements.
The solar option
How much solar does the GBO require for an existing building?
For a full roof replacement on an existing building, Denver's rules call for on-site solar covering 5 percent of the building's gross floor area, 42 percent of the total roof area, or enough to provide 100 percent of the building's estimated annual electricity use. For a single roof section, the requirement is prorated to that section. The coverage area includes code-required access and clearances, and panels must have at least an 18 percent efficiency rating.
How long do I have to install solar after my roof is replaced?
Under the GBO rules, owners of existing buildings have up to 12 months from final inspection and approval of the roof replacement to complete the solar installation. If the panels are not installed in that window, the building is automatically enrolled in the Energy Program.
Can I combine solar with a payment to the Green Building Fund?
Yes. If you cannot provide all of the required solar or green space coverage, the rules allow you to provide at least 75 percent of the requirement and pay into the Green Building Fund for no more than the remaining 25 percent.
Why choose solar over a green roof or a fund payment?
A fund payment is a one-time cost with no return, and a vegetated roof adds irrigation and maintenance. Solar produces electricity that lowers operating costs for decades, and we help you capture every credit and incentive available in your area. Under the city's April 2025 Energize Denver updates, on-site or off-site renewables owned within Denver also count at a 1.5x credit multiplier toward Energize Denver requirements.
Planning a roof replacement in Denver?
Request a GBO compliance review. We confirm your requirement, compare every solar sizing pathway, and show the lowest-cost system that meets the ordinance and pays you back.
Get a GBO Compliance Review