Just before Boulder City Council ended one development moratorium Tuesday, it extended another.

Council approved a new method for developers to get exemptions to building height limits by requiring increased affordable housing opportunities to the city for height boosts for fourth and fifth stories that take structure above 35 or 38 feet. The decision came before council lifted a moratorium on new construction in the east-central Boulder federal opportunity zone.

Those heights were what council imposed as the citywide caps in 2017, with most zoning districts allowing for up to 35 feet and some up to 38, when it adopted a moratorium on granting exceptions to potentially allow structures up to 55 feet, the citywide limit approved by voters in 1971. Industrial zones let structures stand up to 40 feet.

But council responded to what it viewed as more frequent requests for buildings above 35 or 38 feet with the ban on considering them, except for in eight sections of Boulder where height exemptions may still be granted under the moratorium.

Those are University Hill, 29th Street Mall, Boulder Junction, Gunbarrel, a small block on north Broadway, a block west of Foothills Parkway just south of Baseline Road and an area on the north side of Arapahoe Avenue.

Before the height exemption ban developers could request to exceed the limits allowed by zoning districts without providing any extra public amenity to the city, such as more affordable housing, than normally required by city rules. The exception could be granted through the city’s site review process, which requires Planning Board approval, compliance with criteria on building and site quality, compatibility with the surrounding neighborhood and a finding the proposed building height is in proportion with that of other structures in its vicinity.

Under the new rules, developers would have to make 36% of a project’s housing units that are above the height limit in a fourth or fifth story affordable dwellings to low and middle income households, more than the normal 25% requirement for new buildings under the 35, 38, and 40-feet height limits, and for floor area beneath the limit in buildings that exceed the height limit.

For non-residential projects, developers would be subject to affordable housing linkage fees that are 43% more than standard rates for the square footage above the zoning district height limits. Those fees for office space are currently $18.27 per square foot, a rate set to jump to $24.14 in 2020 and $30 in 2021.

The Boulder Chamber in a letter to council contested the basis of city-hired consultant Keyser Marston Associates’ economic analysis justifying those higher affordable housing fees as feasible for developers to meet with the value added by increased height.

“The clear implication from the review by our members of the KMA pro forma analysis is that it does not provide a complete picture of development costs in Boulder,” the Chamber letter stated. “As a result, these local development professionals believe the proposed community benefits for additional height leave insufficient incentive for them to consider adding space above the 35 feet height mark and, thus, it will simply act as a de facto permanent limit on building heights above 35 feet.”

Chamber Director of Public Affairs Andrea Meneghel further explained to the Camera the consultant’s analysis makes sense for large buildings proposed by national developers to request height exemptions, but not everyone looking to do business in Boulder.

“I’m afraid it’s just the big guys that (will) continue to play,” Meneghel said.

Council, also against Chamber suggestions, left in place the regulation allowing height exemptions to be granted only in select areas of the city through May 2021, adding the city-owned Alpine-Balsam site and a residential high-density zone off of 28th Street and Colorado Avenue to the list of areas that can be considered.

Councilman Aaron Brockett pushed to scrap that restriction and open much more of Boulder, and specifically a business zone west of 28th Street, to height exemptions with the provision of extra affordable housing. Under the ban of height boosts through 2021, developers can be granted exceptions anywhere in the city if they dedicate at least 40% of a building’s entire floor area to permanently affordable housing.

“I was surprised when I saw the proposal, and continue to be surprised that we’re only still allowing it in such limited areas,” Brockett said. “If it’s a good project, it seems like it would reasonably apply to more places.”

City staff has proposed keeping the areas eligible for height modifications slender until the second phase of the project is complete, which it anticipates will be May 2021, when the moratorium on added height for the rest of the city is expected to be released. The next phase will analyze how other public benefits like below-market rate commercial space or space dedicated to arts could be provided in exchange for a height increase.

Brockett also questioned whether staff had considered removing site review requirements for projects requesting a height modification that meet all the greater affordable housing demands, and allowing those projects by-right, meaning through staff-level approval, rather than through Planning Board.

City Planner Karl Guilder said that had not been considered as part of this phase of the height tradeoff project, and rather the updated regulations are meant to make the site review process more predictable.

While officials considered exempting nursing home and assisted living facility projects that request height boosts from paying the extra affordable housing fees, they backed off that idea and such developments will be subject to the stricter requirements to go taller. Brockett voiced support for exempting the end-of-life care facilities wanting height from the higher fee tier.

“If we’re going to get (nursing facilities) that’s only serving the upper-income levels, because these are expensive, wouldn’t it be worth staff working over so that we got the right level of affordability if it’s a high-end project,” Weaver said. “… If it’s going to be five stories, we want more.”