The engineers and climate science enthusiasts living in Arvada’s Geos homes are famously in control of everything in their 28-home neighborhood.
They can tell you that when it’s 20 degrees outside, an efficient exchanger can transfer 90% of the indoor air’s existing heat energy to incoming fresh air. They can tell you how far their homes need to be spaced apart to capture the optimal sun angle to save a third of annual energy costs through window positioning alone. They can tell you at any moment the level of carbon dioxide trapped in their super-efficient, air-tight homes down to the parts per million, and import more fresh air with the click of a button.
What’s driving this meticulous community nuts is that they can’t control much of anything beyond their sidewalk.
“This is like an infant that we’re trying to raise to be a child, OK?” said Dar-Lon Chang, a former oil company engineer and a Geos proponent, showing off some of the technology that makes his neighborhood net-zero in energy use. “And it’s under threat of being choked to death because there’s powerful industries who don’t want to have any change.”
The developer of the first batch of net-zero homes, Norbert Klebl, had to sell the remainder of the planned Geos neighborhood along Ralston Creek to settle a divorce. The developer and builder of the next phase of homes say they will honor many of the environmentally-friendly net-zero designs carried out by Klebl and his fellow first-phase residents.
But they will also bring in traditional natural gas lines for stoves, hot water heaters and barbecues.
The current residents are furious at this perceived breach of their careful community plan, and are appealing to local and state politicians to stop what they see as an assault on their principles and a grand experiment to demonstrate healthier communities. They note, for example, that cities including Denver plan to block natural gas connections in new home construction in just over two years from now.
Why, they ask, should Arvada let the fossil fuel mentality get baked into their neighborhood when climate rules will change before the new homes are even done?
“There is this void of institutions, like builders, brokers, appraisers — all these people who haven’t connected yet to the future,” Klebl said, staring at a poster-size schematic he printed of the proposed neighborhood. Only his small corner of the layout is finished so far. “I think in 10 years, all the houses will be built like this. But we need to accelerate it.”
The struggle for fans of the Geos model has been crossing from the technical world to the legal and political realms. A dozen state legislators wrote to the next-phase developer, Chad Ellington of Peak Development Group, to ask the company to reconsider adding gas lines to the plans. Ellington, who did not respond to email requests for an update, has told the current residents in emails that builders will stick with net-zero designs but the new homes are not marketable without a gas option.
Arvada Democratic Rep. Brianna Titone, who organized the legislators’ letter, said as frustrating as the plans are, there’s no policy recourse for now. The most that local politicians can do, Titone said, is bring attention and moral support to a community that’s attracted international acclaim for its engineering and philosophy.
“It’s our job to point this out and let the court of public opinion do what it can to have people be outraged, frankly, about this,” Titone said. “Because I have no doubt in my mind that if they built the houses the way they were intended to be built — the same way that the original homes were built — that people would buy them.”
The current Geos residents have tried Arvada City Council, too, with no better luck. Klebl and Chang say the first phase was built with the blessing and great interest of a more welcoming city leadership, which was then voted out. A letter to the Geos group from city manager Mark Deven lauds the Geos environmental ethos, and details how Arvada is “living the commitment you and others express” in sustainability.
But, Deven adds, the developers and architects have also told the city that marketing the homes is “very difficult” in part because of the gas issue, and because of the expense of some net-zero features.
Geos’ thermal regulatory features include interior climate control and monitoring of carbon and VOC vapor levels. 
Plum and apple trees make up Geos’ budding community garden.
City leadership respects “your passion for this issue and understands your perspective . . . the city does not have the authority to force the developer to provide a certain type of utility to the future phase of the development,” Deven wrote in July.
The Colorado Association of Home Builders said it could not comment specifically on the dispute in Arvada, but its members “report that most consumers in Colorado and around the country still want the options that both gas and electric energy provide in their homes,” association chief executive Ted Leighty said in an email statement.
Large builders have to focus on a broader market than custom builders, Leighty’s statement said. “Right now, the demand for gas appliances, including stoves, furnaces, and fireplaces, remains high,” he said, and the pandemic has increased demand for gas-fired yard barbecues and firepits.
Though Dream Finders, the national builder working with Peak Development, did not respond to requests for comment, it is advertising the Geos development on its website as “the ultimate in green, sustainable living.”
Environment-friendly features will include highly efficient furnaces and tankless water heaters, blown-in insulation, windows that let in light but not too much summer heat, drought-tolerant landscaping, electric vehicle chargers, and solar panels that can send extra electricity out onto the grid, according to Dream Finders.
A Little Free Library is seen with a solar-powered lamp at Geos. 
Geos founder and developer Norbert Klebl shows a model of units’ window insulation, designed to be nearly soundproof.
The assurances from Peak Development and Dream Finders have earned little credit in a tight community where neighborly trust appears as important as the grid connections. Geos homeowners pile out onto the street to add personal details when they see someone new taking a tour of the engineering feats. The whole block shares a wheelbarrow.
Titone looked at one of the homes for possible purchase, attracted by the entire ethos, but never had a chance to make an offer because they were all sold.
“I think the builder is doing a disservice to the community because this community was set to be a model of what we can do and what we can accomplish,” Titone said.
The engineers, retired tinkerers and other professionals who live in the Geos detached homes and townhomes compare notes about solar panel efficiency and composting. Klebl said the first phase of homes was built in such a way that a homeowner’s annual utility costs are about what most in a similar multi-story home pay for a month.
These are the Geos design and building features they will be watching carefully to see if Dream Finders matches in the next phase:
- Full electrification, including heat exchangers, heat pumps and tankless water heaters instead of gas-fired air and water furnaces; induction cooktops instead of gas stoves; efficient electric washers and dryers, all powered primarily by solar panels and battery storage.
- Solar-efficient building positioning and staggering. The existing Geos homes are staggered in a back-of-lot, front-of-lot checkerboard, which allows sunlight into more windows for passive solar heating.
- Insulation and window and door efficiency. While traditional U.S. home design can be drafty “like a tent,” Klebl said, the Geos design spends extra money up front on overlapping insulation and window features like fiberglass frames, rather than materials that warp in the elements and leak. The result is a tight home that exchanges its internal air once every 20 hours, instead of every three to four hours. (When the front door is shut in a Geos home, the interior is quieter than any library.)
- Modern solar grid, including net metering. With the efficient panels wired into the local utility grid, Geos homes produce more electricity during daytime than they use, and put it out onto the grid. They use those generated credits at night, thus the “net” metering. When architects suggested awnings over Geos’ south-facing windows, Klebl found cheap solar panels the size of an awning and plugged those into the grid, too.
Builders who say those features are too expensive are overly invested in doing things the way they always have, the Geos boosters said. Some of the original Geos features may be slightly more expensive up front, because they are custom-designed and purchased in small quantities, they acknowledge. But the nation’s largest home builders have in-house design and ingenuity teams well-accustomed to bringing costs down through efficiency and mass purchases, they added.
Some communities nationally have already formalized bans on natural gas connections in new home construction, they noted. Denver is at work on a building code overhaul with the stated goal of requiring clean-electricity appliances in new homes starting in 2024, and requirements or incentives to retrofit existing homes in the years after that. City officials said there is no update yet on that proposed timeline.
Marketers for big builders often cite choice as a top demand among American consumers, the Geos residents said. But that’s a fake dilemma if the consumers don’t have all the information, they add. Newbies tend to be skeptical of appliances like magnetic induction ranges, because they don’t have the instant-on flame that satisfies many cooks, they said.
But the Geos residents love to demonstrate their own induction cooktops, which require specialized magnetic pots. They can boil water within a minute, can be touched with a bare hand as soon as they are off, and eliminate gas-burning fumes that are an increasing concern of indoor pollution experts.
“So I think we have to accept the fact that Americans want choices,” Klebl said. “But we also have to accept the fact that a larger percentage follows logic.”