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Denver Voters Pass I-300 Green Roof Building Code!

on November 9, 2017 at 5:02 pm under

Denver Voters Pass I-300 Green Roof Building Code

Green Roof Ordinance I-300 Passes from Denver Voters by 52%

After a hard fought battle from both sides, the votes were in late last night: Denver voters approved the I-300 Green Roof Code on Tuesday, November 7.  The initiative passed by about 52.5 to 47.5% of the vote, in spite of the fact that the opposition outspent supporters by a margin of 12 to 1.

Starting January 1, 2018, buildings in Denver larger than 25,000 square feet will be required to green a portion of their roofs either with vegetation or solar.

Battle of the Advertising Budgets

Huge financial support was garnered from the opponents of the measure, who spent an estimated $250,000.  In particular, Denver commercial real estate developers, some businesses, and the opposition campaign “Citizens for a Responsible Denver” were the leading challengers to the proposed mandate.

Contrast that amount to the meager $10,000 collected by the Denver Green Roof Initiative over the past months!  Grassroots leader and Denver Green Roof Initiative Campaign Manager Brandon Reitheimer says most of the money was spent on social media advertising.

And in particular, Brandon emphasized the importance of volunteer canvasing across the city, from homes to Democratic house district meetings to neighborhood association meetings.

Denver Voters Pass I-300 Green Roof Building Code

Denver Botanical Gardens.

Citizen-led Initiative with a Great Reach

The Denver victory is great for all of us in the living architecture field, but especially for the citizens of Denver.  And, hopefully it’s a sign that future municipalities also will provide leadership on sustainability.

The citizen-led initiative had much support from locals and within the greater greenroof community.  Many of us donated money, time, and marketing to the cause, including, Green Roofs for Healthy Cities (GRHC), and others within the U.S. greenroof industry.

Favorable Cost-Benefit Study from Green Roofs for Healthy Cities & Green Infrastructure Foundation

In mid-October, Green Roofs for Healthy Cities prepared a detailed cost-benefit analysis of the economic impact relating to the proposed I-300 Ordinance, entitled Making Informed Decisions: A Green Roof Cost and Benefit Study for Denver.”

GRHC found that widespread greenroof installation would result in 57.5 million square feet of living roofs, and generate $1.85 billion in savings by 2058 and approximately 25,000 job-years in employment over a 15 year period.

“The study doesn’t quantify many important green roof benefits or the solar component in the proposed law. We used conservative data on costs and benefits from Denver which suffers from terrible urban heat island impacts, combined with studies from other jurisdictions that have implemented mandatory green roof requirements,” ~ Andy Creath, Green Infrastructure Foundation board member and president, Green Roofs of Colorado in the 10.13.17 Green Roofs for Healthy Cities & Green Infrastructure Foundation Media Release

Denver Mayor Michael Hancock Weighs In

Denver Voters Pass I-300 Green Roof Building Code

Denver EPA Greenroof.

Mayor Hancock was against the measure, saying it went “too far,” in Denverite but added that the city would implement the will of the people.

“We are concerned that it may mean more initial costs. Once the people have spoken, that’s our job. There may need to be some tweaks, based on legal challenges. Though we were not going to line up and support the initiative, our values align.” ~ Denver is one of the first U.S. cities to require green roofs – so what happens now?

What Does Happen Now?

Regarding the passage of this Initiative, two important items remain:

1. I-300 will be reviewed by a Technical Committee which can put alterations to a vote by the Denver City Council;

2. And in six months, the Denver City Council would have the option of repealing or making changes to the ordinance with a two-thirds majority.

Denver Voters Pass I-300 Green Roof Building Code

Denver Residence on Quivas Street.

Is Denver Ready?

At present, the mayor and city council members are researching all of the possible opportunities and challenges that might be inherent in implementing the initiative. And Andrea Burns with Denver Community Planning and Development says the new ordinance will take a lot of effort, but that they will make it work for the people of Denver.

Green Roofs for Healthy Cities says it will continue to work with local groups, the Technical Committee, and the Denver City Council to strengthen and support the initiative and grow the area greenroof market.

Leila Tolderlund, LEED AP, GRP, an assistant professor in the University of Colorado Denver’s College of Architecture and Planning – and one of our Speakers at the Greenroofs & Walls of the World™ Virtual Summit 2017 – provided commentary to Denverite:

“We’re ready,” Tolderlund said of the landscape architects of Denver. Bring it on.” ~ Denver is one of the first U.S. cities to require green roofs – so what happens now?

Kudos to All

Congratulations to the tireless and persistent volunteers at Denver Green Roof Initiative, in particular Brandon Reitheimer, for their incredible work on passing the first fully citizen-led ballot initiative of this kind in Denver!

Additional work needs to be accomplished to keep Initiative 300 on track for next January 1, and you can count on us for continued media support.

Denver Voters Pass I-300 Green Roof Building Code

Community College of Denver.

For additional information, contact Brandon Reitheimer at or call (717) 433-3663.

By Linda S. Velazquez, ASLA, LEED AP, GRP Publisher & Greenroofs & Walls of the World™ Virtual Summit Host

Register now and join us online for our 2017 Virtual Summit through December, 2017.  Round #2 started on October 16th!

Denver Voters Pass I-300 Green Roof Building Code


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