Complying with the Green Buildings Ordinance

“Green space” is any area open to the sky and containing trees, groundcover, shrubs, urban agriculture, natural grass, turf, or a vegetated roof. Green space can be provided on a roof (a vegetated roof or “green roof”) or at grade.

For this compliance option, the ordinance requires an amount of green space related to either the gross floor area, total roof area, or available roof area. To calculate available roof area, start with the total roof area and deduct the following:

• Private terraces equal to or smaller than the gross floor area of the abutting unit at the roof level
• Outdoor amenity spaces, including but not limited to areas for recreational or social use
• Rooftop mechanical, electrical, or other equipment, including cell towers and other equipment leasing space on the roof, and all required clearances around these areas
• Skylights
• Glass-covered atriums
• Glazing (windows)
• Areas covered by renewable energy devices

Green space at grade

Existing green space cannot be used to meet the green buildings ordinance, unless it is improved with trees or an above-grade, vegetated, water quality facility. Review the following information in the Rules and Regulations:

• Requirements for trees
  • Protecting or adding trees in the public right-of-way
• Water quality facility

New buildings that have a vegetated storm water treatment area or a zoning requirement for open space can count these spaces, provided the area meets Section 4.02(e)(1) of the Rules and Regulations.

Zoning permits for green space at grade

Denver’s site development plan (SDP) review team will review any proposed green space on the ground to ensure it meets zoning standards as well as the green buildings ordinance.

First, read Section 4.02(e) in the Rules and Regulations. This section details minimum planting area sizes, what qualifies as climate-appropriate vegetation, guidelines on irrigation/potable water use, and when soil testing is required.

Then, include the following information in your submittal:

• Cover sheet that includes the building area calculation and the following note:

• Green space is shown on this site development plan for compliance with Article XIII of Chapter 10, must be maintained, and cannot be used for purposes other than that shown on this site development plan. Should a future amendment change the amount or location of this green space, then additional green space must be provided to document compliance or payment of cash-in-lieu fees will be required.

• Site plan
• Roof plan
• Maintenance plan
• Landscape plan
• Photometric plan (only if new lighting is being installed)

Green roofs

Green roofs are subject to the design and construction requirements detailed in Article IV, Section 4.02(d) in the Rules and Regulations. Read this section carefully before submitting architectural, structural, plumbing, electrical, or mechanical plans for a green roof.

Construction plans for a green roof must be accompanied by maintenance and irrigation plans that include the items listed in Section 4.02(d)(ii)(4-5) in the Rules and Regulations. Vegetation and growing media specified on the construction documents must coordinate with the maintenance plan.

Green roof construction permits

Projects incorporating a green roof will receive a building permit for the green roof and a standard roof permit for the underlying roof/waterproof membrane of the building.

The green roof permit requires a Denver-licensed green roof installer. Licensed roofing contractors will need to obtain licenses in lawn irrigation and green roof installation to build green roofs. The lawn irrigation and green roof licenses help ensure a high standard of green roof construction by individuals who are skilled in selecting vegetation appropriate for Denver’s climate and equipping it for successful growth and maintenance going forward, long after a green roof installation is complete.

The lawn irrigation and green roof installation licenses are designed for people with irrigation and landscaping experience and do not explicitly cover roofing, so a licensed roofer or building contractor will need to be part of every green roof project.

Reference:

• Section 4.02 of the Rules and Regulations(PDF, 2MB) for green space/green roof requirements
• Section 4.06 of the Rules and Regulations(PDF, 2MB) for green space in combination with other compliance options

The green buildings ordinance allows buildings to provide onsite renewable energy or to purchase it through five-year contracts from Xcel or a community solar project.

Purchasing renewable energy

• Today, off-site renewable energy can sometimes be purchased from Xcel Energy’s Solar*Rewards Community®. Contact SolarRewardsCommunity@xcelenergy.com with questions. Capacity may be limited since new Community Solar*Rewards solar gardens are limited in quantity and often sell out quickly. 

• Learn more or join the waitlist for Xcel's Renewable*Connect program. 

• Xcel's Windsource program does not allow buyers to purchase from dedicated renewable energy resources. Buyers would be purchasing kWh (electricity used) rather than kW (renewable energy production), so this program does not meet the green buildings ordinance.

If your project is purchasing renewable energy, include an energy model in your permit submittal that indicates the anticipated consumption.

When purchased renewable energy is less than 100% of the building’s consumption, the purchased renewable energy must provide the same amount of electricity as the required amount of onsite solar panels would have achieved and the submittal must demonstrate that the building will achieve the requisite energy cost savings.

Before the building can receive a certificate of occupancy (CO), the building owner must present the five-year contract for the renewable energy purchase. A new contract must be submitted every five years or upon expiration of the previous contract for the life of the building. Email contracts to energizedenver@denvergov.org.

Installing onsite solar or renewable energy

Include the following in your submittal:

• All documents listed under “Solar Photovoltaic Systems” in building code policy IRC R324(PDF, 216KB) – These are standard requirements for any solar permit.
• Manufacturer’s specifications documenting the panels’ efficiency rating. The minimum efficiency rating allowed under the ordinance is 16%.
• If the amount of solar coverage provided is based on the project’s roof area, make sure the roof plan submitted outlines the total roof area and identifies all panels, equipment, and clearances.
• If the amount of solar coverage provided is based on the system’s ability to generate 100% of the building’s annual electricity use, include the most recent complete year’s annual electricity use in your submittal. For new buildings, include an energy model indicating the estimated annual electricity use.
• If you are using an alternative renewable energy source, submit documentation that it generates similar capacity as the required amount of solar panels would have achieved.

Existing solar panels can count toward the solar coverage requirements of the ordinance, provided the panels have a minimum efficiency rating of 16%.

Solar panels that are not flush-mounted to a roof (within one foot of the roof surface and parallel to the roof) will require a zoning review. Projects in a historic or landmark district will need approval from Landmark Preservation before applying for electrical, zoning, or building permits.

Net zero energy

For buildings proposed to be net zero energy, include an energy model and energy use intensity (EUI) showing the estimated annual energy use wholly offset by the onsite renewable energy source.

After operating at 60% or more of normal occupancy for 12 months, email the following to the Denver Department of Public Health & Environment (DDPHE) at energizedenver@denvergov.org:

• Confirmation that the systems and building are performing as anticipated and the building has met the requirements of a net-zero energy building
• An analysis of the solar panels or other renewable energy source
• A continuous 12-month period of utility bills starting after the temporary certificate of occupancy (TCO) was obtained and 60% of normal occupancy levels were achieved.

If the variance is greater than 5%, the system will need to be reevaluated and corrective measures proposed.

References:

• Section 4.03 of the Rules and Regulations(PDF, 2MB)
• Section 4.06 of the Rules and Regulations(PDF, 2MB) for combination green space/renewable energy approaches

To demonstrate an energy cost savings beyond the current building code, include the following in your submittal:

• An energy model indicating baseline code compliance and a predicted EUI for the building (with the assumptions that went into making that prediction)
• In a separate section of the report, identify the items being included in the design that exceed code. Clearly delineate the additional systems, their above-code performance features, and scope of work.
• All other energy code compliance items listed in the IECC Commercial Provisions building code policy(PDF, 1MB). These are standard requirements for any commercial building permit.

Before the project can receive a temporary certificate of occupancy (TCO), a preliminary commissioning report must be submitted indicating that the items have been installed in accordance with the manufacturers’ recommendations and are performing as designed and intended.

References:

• Section 4.04 of the Rules and Regulations(PDF, 2MB) for Energy Cost Savings
• Section 4.06 of the Rules and Regulations(PDF, 2MB) for combination green space/energy efficiency approaches

Include the following with your permit application submittal:

• The LEED design package, scorecard, or equivalent
  
  • For existing buildings, this can mean LEED Silver (BD C or O&M), National Green Building Standard (NGBS) ICC/ASHRAE 700 Silver, or Enterprise Green Communities.
  • New buildings can meet LEED v4 BD C Gold, NGBS ICC/ASHRAE 700 Gold, or Enterprise Green Communities. Before a certificate of occupancy (CO) can be issued, the building will need to either be pre-certified or must submit the LEED design review (or equivalent) with a plan for how any requested changes will be made. Within 18 months of receiving a CO, submit proof of certification to CASR by email at energizedenver@denvergov.org.

Other equivalent certification programs that encompass the entire building may also be accepted.

Reference:

• Section 4.05 Building Certification of the Rules and Regulations(PDF, 2MB)

$50 per square foot of green space required but not provided

For each project that elects to pay into the Green Building Fund instead of meeting another compliance option, CPD will calculate the amount owed based on the amount of green space that would have been required. The fee amount is $50 per square foot of green space required.

When a project is able to provide at least 75% of its green space requirement, but not the full amount, the owner can elect to pay $50 per square foot for the green space not provided, up to a maximum of 25% of the required green space coverage.

This fee must be paid before permits will be issued.

More about the fund

The Green Building Fund is managed by the Department of Public Health & Environment. The money must be invested into the following purposes, with priority given to low-income areas that have less green space and trees, high-impact projects, and green spaces located near the buildings that paid into the fund:

• Green space acquisition and improvement (ecosystem protection and restoration, such as native plantings or native plantings as part of invasive species control)
• Water quality improvements and green infrastructure
• Urban forest protection and expansion
• Installing green roofs in partnership with land owners/developers
• Driving rooftop solar or community solar adoption among low-income and affordable housing developments

Rate Study(PDF, 3MB)

The Energy Program is managed by the office of Climate Action, Sustainability & Resiliency. To learn more on how the Green Buildings Ordinance Energy Program and Energize Denver Ordinance requirements align, visit the:

Green Buildings Ordinance Energy Program webpage

“Cool roof” roof covering materials must meet the solar reflectance values in the table below. For existing buildings that are only replacing sections of the roof and not the entire roof, a “roof section” is roof bounded on all sides by a wall, parapet, edge, expansion joint, or roof divider.

Roof areas exempt from providing a cool roof:

• Area covered by solar systems or components
• Area covered by solar air or water-heating systems or components
• Green roof areas
• Above-roof decks or walkways
• HVAC systems and components and other opaque objects mounted above the roof
• Swimming pools, sport surfaces, and glazing
• Portions shaded during the peak sun angle on the summer solstice by neighboring buildings or other portions of the same building
• Portions ballasted with a minimum stone ballast of 15 pounds per square foot or, in the case of an existing ballasted roof, the weight of ballast for which the roof was originally designed
• Roof sections visible from a public vantage point (like a publicly accessible street, park, or campus), so long as this portion does not exceed 10% of the total roof area
• The remainder of a roof section where at least 75% of the section meets the exemptions above, is a character-defining roof, or is a cool roof

Submit a roof section drawing

For all projects incorporating a cool roof, include the following in your submittal:

• Submit a roof section drawing
• For steep-slope roofs, design to meet IBC 1203.2 (ventilation)
• For low-slope roofs, provide at least Class III vapor retarder and air barrier at deck (can be one product) & above-deck insulation exceeding any below-deck insulation by at least R-18 (IECC insulation minimums still apply)
• If the roof does not meet the code requirements above, also submit an analysis by a professional roof consultant, architect, or engineer indicating dew point, location of barriers, etc. to demonstrate how condensation issues will be mitigated

All drawings and documents prepared by an architect or engineer must bear their professional seal and a valid electronic signature.

Reference:

• Section 3.02 Cool Roof Requirements of the Rules and Regulations(PDF, 2MB)
• Cool roofs fact sheet(PDF, 217KB)

Administrative Modification Request

Property owners may apply for an administrative modification to propose specific roof materials not itemized or included in the solar reflectance table above.

Administrative modification requests must be submitted though e-permits.

A character-defining roof must be at least partially visible from a public vantage point, like a publicly accessible street, park, or campus. The roof’s relationship to the overall shape of the building and its distinctive materials, craftsmanship, or decorative details must be important to the overall visual character of the building. If the materials, color, or shape of the roof were to change, it would impact the visual character of the building. For buildings that have character-defining roofs, the cool roof requirement may be reduced to allow the use of materials and colors that keep with the visual character of the building.

To request a character-defining roof determination, include the following in your submittal:

• Roof plan (new buildings only or existing buildings if a roof plan exists)
• Photographs of the building and the roof from public vantage points (existing buildings only)
• Elevations (new buildings only since photographs would not be possible)
• General information about the proposed roof materials, color, and finish; the materials’ solar reflectance; and the importance of the roof in context of the building or its location
• Demonstrate at least one of the following:
  • The roof is highly visible and contributes to the architectural identity of the building or its context.
  • There are certain roof features important to the profile of the building against the sky or its background, such as cupolas, multiple chimneys, dormers, cresting, or weather vanes.
  • The roof material’s color or patterns (such as patterned slate tile) is more noticeable than the shape or slope of the roof.
  • The roof is identified as being an integral part of the building’s character and an identified feature for any historically designated building in its designation materials. Such historical designation may be local, state or national.

Staff will review this information to determine whether the roof is a character-defining roof or if it will need to comply with the cool roof provisions of the ordinance.

Guidelines for Submitting Dew Point Analysis Reports for Green Buildings Ordinance Reroof Projects(PDF, 286KB)

Projects that submitted a formal site development plan (SDP) or complete building permit application and paid review fees under the previous green roofs ordinance have the option of continuing to meet the previous ordinance or submitting revised drawings to meet the new ordinance. There is no required completion date for projects continuing under the old ordinance. 

Archived resources for projects continuing under the old ordinance:

• Previous "Green roofs ordinance" language(PDF, 4MB) (November 2017)
• Rules and Regulations for the old ordinance(PDF, 1MB)
• Declaration Form(PDF, 245KB)

Guides for existing buildings

• Building additions requirements for existing buildings(PDF, 174KB)

• Building certification requirements for existing buildings(PDF, 156KB)

• Renewable energy requirements for existing buildings(PDF, 204KB)

• Cool-roof-requirements for existing buildings(PDF, 132KB)

• Energy program requirements for existing buildings(PDF, 149KB)

• Enrolled in energy program requirements for existing buildings(PDF, 145KB)

• Green space requirements for existing buildings(PDF, 209KB)

• Payment into the green building fund requirements for existing buildings(PDF, 215KB)

Guides for new buildings

• Payment into the green building fund requirements for new buildings(PDF, 213KB)

• Renewable energy requirements for new buildings(PDF, 181KB)

• Renewable energy requirements for new buildings(PDF, 165KB)

• Building certification requirements for new buildings(PDF, 152KB)

• Energy savings requirements for new buildings(PDF, 120KB)

• Green space requirements for new buildings(PDF, 188KB)

• Green space and energy savings requirements for new buildings(PDF, 195KB)

• Green space and off-site solar requirements for new buildings(PDF, 205KB)

• Green space and on-site solar requirements for new buildings(PDF, 219KB)