Mandate Plants On Building Roofs? Denver Ballot Initiative Says, Yes

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Photo: Green Roof Community College of Denver
A green roof at the Community College of Denver.

Big, new buildings in Denver would have to be topped with plants if a ballot initiative passes. Supporters say green roofs combat rising temperatures in the city, among other benefits. Critics don't disagree, but say a mandate is the wrong choice.

Initiative 300 would mean new buildings larger than 25,000 square feet must dedicate some of their roof space to trees, plants, solar panels or a mix. The bigger the building, the more covering required.

Existing buildings aren't covered unless they expand to above 25,000 square feet, or if they need a new roof. There are some exclusions for smaller apartment buildings and condos.

We brought the two sides of this initiative together for a debate.

Ean Thomas Tafoya of the Denver Green Roof Initiative, and Katie Kruger with Citizens for a Responsible Denver which is opposed.

They spoke with Ryan Warner.

Read The Transcript

Ryan Warner: This is Colorado Matters from CPR News. I'm Ryan Warner. Big new buildings in Denver would have to be topped with plants if a ballot initiative in Denver passes. Supporters say green roofs combat rising temperatures in the city among other benefits. Critics don't disagree, but they say a mandate is the wrong avenue. We're going to debate this now with Ean Thomas Tafoya of the Denver Green Roof Initiative and Katie Kruger, of Citizens for a Responsible Denver, which is opposed. She's on the phone and welcome to you both.

Ean Thomas Tafoya: Hi.

Katie Kruger: Thanks, Ryan.

RW: Initiative 300 would mean new buildings bigger than 2,500 square feet must dedicate some of their roof space to trees, plants, also solar panels can be in the mix. The bigger the building, the more covering required. Existing buildings aren't covered unless they expand to above 25,000 square feet or if they need a new roof. There are some exclusions I'll say for smaller apartment buildings and condos. Ian, what's so beneficial about green roofs that you think they should be mandated? Give me your elevator pitch.

ET: Yeah, thanks again. It's a pleasure to be here on behalf of I300, the Green Roof Initiative. I300 is a citizen driven ordinance on the ballot this election. The ordinance requires…

RW: What would you say are its benefits?

ET: Obviously it cleans the water, it cleans the air. It reduces the temperature. There's energy savings. It provides habitat for animals and it provides kind of a green space often for people to participate in. But I do want to point out that trees, we combat this a lot, trees is a very extreme, intensive case of green roofs. Most of the examples that you see here in Denver are nothing like that. There's succulent plants based in four inch medium and they clean the water and do all those great things.

RW: Based in four inch medium meaning there's some sort of soil atop a roof?

ET: Yes, absolutely. When you think about green roofs you need to think about kind of how you put on coats, right. These are different layers that add up. You have this base layer that keeps the water out. You have these layers that help hold in the soil then you add the plants.

RW: You said obviously this cleans the water. I don't know why that's the case.

ET: The reason that it obviously cleans the water is the same reason that why we use bioswales or why we have these great projects that restore the greenery around rivers because the soil microbes and the plants naturally clean the water.

RW: Okay, water that falls from the sky on top of a building would sort of go through this green roof system.

ET: Yeah, it filters down through, eventually ends up in the waste water stream.

RW: Speak briefly to the heat benefits here.

ET: Yeah, so the heat island effect, which everyone talks about is basically you have all this concrete that takes in energy from the sun all day and then it radiates it back out. By not having a black roof and having plants instead in the soil, it lowers the temperature that you would have instead.

RW: So critics say the upfront costs would be passed down to renters and would make public projects more expensive. The Denver Post reports the cost to install a rooftop garden could be anywhere from $25 to $35 a square foot, that could add thousands or hundreds of thousands of dollars to costs. How would this cost effect affordability in Denver, particularly in the housing market, which is of such concern these days?

ET: Yeah, I think what we're failing to see here is a long-term vision. When we're talking about quarterly earning reports, are we talking about 25 years from now? Most of the research that's been done including by the state of Colorado Energy, they show that it pays it back in 6.2 years.

RW: Is it the Energy Office, you're saying?

ET: Actually the office that I'm thinking about is PACE, which is the energy tax incentive that gets people to advance their buildings.

RW: You say then the costs can be recuperated if you're looking long term?

ET: Yes, absolutely.

RW: How are the costs recuperated?

ET: By energy savings.

RW: Katie, your opposition group has the support of numerous businesses including the Denver Metro Chamber of Commerce and the Denver Metro Association of Realtors, of which by the way you're CEO. You're not opposed to green roofs I understand, you're opposed to the mandate. Why should someone in Denver be concerned about Initiative 300 in your opinion?

KK: Thanks again for having us, Ryan. We really appreciate the opportunity to speak. It is the mandate issue that we are tripping over the most. It isn't just a concern for the people in Denver. It's going to be a concern for Coloradans all across the state because it's going to drive up housing costs and push out small businesses. When you drive up housing costs in the core of our state, those people looking to find more affordable options, whether that be for their own housing or for moving their small businesses to someplace more affordable, they're going to start to put pressure on the surrounding municipalities and those surrounding metro areas. That demand is going to drive up housing costs for everybody in our state.

RW: What about this idea that costs can be recuperated over the life of a project? Is your view of cost very short sighted do you think?

KK: So our builders and developers in Denver, it's an exciting and tenacious market. Everybody kind of wants to be here and we want to keep it that way. They're always contending with kind of labor shortages and rising material costs. They're very good at finding any kind of natural cost savings measures. So we believe that if these kind of energy efficiency uses and green retrofitting pieces were actually going to improve their budget, they would already be doing it.

RW: What do you say to that Ian, the idea that if there's such a savings to be had, builders would be doing this of their own volition?

ET: What I would say is that builders again are trying to maximize their profits. It's funny that we have the CEO talking to us about affordable housing. The linkage fee in Denver, which is the backbone and the crux of the funding for all affordable housing in our communities was opposed by this CEO and by their office. The energy savings, Energize Denver, which the Denver Office of Sustainability has been touting, they also opposed. We think it pairs well with tax credits that are already being offered by the state of Colorado. It's funny right before your show, I heard that the public housing authority in Aurora was talking about a solar garden they were turning on and the energy savings that they were about to receive.

RW: I'd like to say that on your side, the Denver Green Roof Initiative is backed by environmental advocates and some developers like Zeppelin and Peak One. Zeppelin has a huge project right now in Denver's RiNo neighborhood. Cities like Toronto, Washington DC, San Francisco have all implemented green roof ordinances with some success. Katie, what do you say when you look at other communities that have greener roofs than Denver and whether this is a city lagging behind?

Katie Kruger: Well first Ryan I think that I'd like to just mention that we've been a part of the collaborative process putting in place that mandate for Energize Denver and we're really proud of the stakeholder outreach that occurred there. And Denver is now, and for the voters, that's requiring all Denver property owners to list their Energy Star Rating of their building for public view. And that's something that we believe naturally drives the market, so it's very positive. And we were at the table for those conversations and we have almost 100 percent compliance of that initiative, of that mandate in Denver, except there is one kind of major well known outline developer. And that is Zeppelin Development and they are endorsing this new Green Roof Initiative and mandate, all the while not participating in this kind of basic mandate of being transparent.

And we're aware of San Francisco. You know San Francisco is known to be one of the least affordable markets in the country. They are 63 percent more expensive for small businesses to find office space there and about 135 percent more expensive when you're seeking a condo or an apartment in those markets. And so most Coloradans would agree, we don't want to be San Francisco here.

RW: You're listing to Colorado Matters. I'm Ryan Warner and we're debating Initiative 300 on Denver's Ballet, this has to do with green roofs and mandating them. Ian go ahead.

ET: Well I just want to respond to what she had to say about being collaborative in the process. I mean I read your website where you said you absolutely oppose Energize Denver and the linkage fee, but beyond that I don't think we're anywhere close to 100 percent compliance. We're about 72 percent, and we're not even fully into it and we had to mandate it. Just like the building code, right? Because these developers in these buildings aren't moving us towards that. And to say that this one piece of technology, which takes a look and takes a hack at eight of the 12 sustainability goals is going to drive up rents and all these other things, just like San Francisco, there's a whole lot of other things in play in the market than just one rooftop technology.

RW: Just to note, you mentioned earlier our newscast item on a housing authority that's starting a solar garden, it's actually in Denver not Aurora. Just to make it clear on that.

ET: Oh it's in Denver?

RW: Yeah.

ET: Great.

RW: Why go the initiate route Ian? Why not do this through, say City Council and that sort of legislative path?

ET: Well I mean I think we really have tried. Going all the way back to 2008 Green Roof Initiative, the green roof advocates came together with then Mayor Hickenlooper's administration, and we even produced documents that really pushed us forward. And you can see it implemented on several city buildings, including The Justice Center. About a year ago we came to the city, and we asked them, and they turned us away. Office of Sustainability, the Building Department, they said, "Right now we're just not in a position to take that." Well if you look at what else is happening in the world with the climate change, and you look at the auditor's report, which eviscerated the Office of Sustainability for not making any meaningful progress, we looked at it and said, "We know leaders don't like being told what to do, but we can't sit on our hands anymore." And we did something that no one ever did before, and that was gather 8,000 signatures and turn them in with 60 unpaid volunteers and we were told by the Clerk and Recorder it's never been done before.

RW: It's never been done before? The people haven't gathered signatures…

ET: Without, without, without a paid petitioner.

RW: Okay.

ET: We did this all volunteer base, environmentally group led.

RW: Got it. Denver's mayor, I'll say, is opposed to this mandate saying that this is not the right time. Katie, what if this measure is approved by voters? I'll give you that last word.

Katie Kruger: Yeah, you know we're going to use the resources available to us to kind of back the process up and be collaborative. You know we'd like to bring the stakeholders to the table, including the proponents, and people like Denver Public Schools who are going to be dealing with now a seven, in that case they would be dealing with seven figure line items that draw them away from funding good education for our children. So we would back the process up and start it collaboratively the Denver way. And talk to our city officials and see how we can blunt the blow of this. If it were to go into play even for just a few short months, the negative impacts on Denver's economy will ripple out into the future, and out into the surrounding metro areas, for a very long time to come. So I have a feeling Ian and I will probably talk to each other even more down the road.

RW: That is a fairly dark picture that Katie paints there of DPS having to divert money to green roofs and take it away from education, educating kids, of the market more generally.

ET: Can I respond to that?

RW: Yeah very quickly. I mean what happens if this is not approved? What avenue do you take?

ET: Well first of all if we don't win, absolutely a collaborative process, we're not going away. I really want to tell environmentalists that, you know, we need to keep the pedal on the gas, we're almost there, we're pushing our politicians to do the right thing. And now as far as schools go, again I think we're losing sight of the fact that there's long-term savings here to the line items. And furthermore, there's a huge difference when you look at a budget that has to do with the amount of money you spend in the classroom, and what you do to maintain the buildings. I think they're different and the bonds that we often pass have to do with infrastructure, so we're choosing to fund those kind of advancements.

RW: A vision of capital construction versus -

ET: Yeah and they're learning classrooms for children, they're great.

RW: Thanks for debating this with us. You heard from Ean Thomas Tafoya of the Denver Green Roof Initiative and Katie Kruger from Citizens for a Responsible Denver. You can read Initiative 300 in full at