Posts tagged with "Seattle":
Architects and developers building across much of Seattle will soon have to meet the city’s new Mandatory Housing Affordability (MHA) requirements, a set of rules passed with a spate of recent comprehensive zoning changes designed to ensure that “new commercial and multifamily residential development contributes [new] affordable housing.”
The MHA regulations were approved this spring and are expected to add over 6,000 new low-income housing units to the city’s housing stock over the next decade. The changes are part of the city’s Housing Affordability and Living Agenda, a three-pronged effort undertaken by city agencies several years ago to increase housing supply in order to stem escalating rents and property values across the thriving region. The fiercely contested changes in land use will allow for a greater level of residential density in many of the city’s neighborhoods and will ask builders to either include affordable housing on-site or pay into a general fund that can be used by city agencies to create new affordable housing in other areas.
The new regulations span five categories of development density, from low-rise detached and row house neighborhoods to taller mixed-use districts where buildings will be allowed to rise to a height of 95 feet or more. The efforts will upzone roughly 6 percent of the city’s single-family zones. Single-family zones ultimately make up over 80 percent of the city’s residential areas.
MHA regulations, according to planning documents provided by the City of Seattle, will be pegged to the degree of upzoning that takes place: Under the plan, areas that have been upzoned most significantly will be required to add a relatively higher proportion of new affordable housing. The required fees administered in lieu of on-site affordable housing construction will start at $5.58 per square foot for projects located in low-rise areas outside downtown Seattle and will go as high as $35.75 per square foot for larger mixed-use developments, according to city agencies.
The requirements will necessarily affect the work of architects designing buildings in these areas, but it is so far unclear exactly how. The MHA requirements are set to go into effect immediately, as the city’s rezoning initiatives are approved on a neighborhood-by-neighborhood basis.
Thanks to LMN Architects, Seattle has a new space for making experimental music. The recently opened Octave 9: Raisbeck Music Center performance and educational music facility brings new state-of-the-art sound experience capabilities right to the city’s Benaroya Hall symphony complex, which was also designed by LMN 20 years ago.
The new music center is spectacularly technical in terms of its offerings, and includes a custom-designed acoustically absorptive ceiling and 13 curving screens hung on circular tracks that can create nearly-360-degree immersive and interactive projections. The facility's speakers, microphones, projectors, lighting, and HVAC are all integrated into the absorptive ceiling while a professional-quality Meyer Constellation digital acoustic system is sophisticated enough to allow musicians who use the space to engage in cross-genre performances.
According to the architects, the sound system enables a “spatial sound” experience, created when individual speakers across the room play selective sounds to create the impression of movement.Octave 9: Raisbeck Music Center at Benaroya Hall 200 University Street Seattle, Washington Architect: LMN Architects
Seattle is updating building codes for new skyscrapers after a shocking study revealed that the power and nature of earthquakes in the region pose a significant threat to its tall buildings, one that is worse than experts could have imagined.
The Seattle Times recently reported on results from the M9 Project, a four-year study that aimed to estimate the effects of a magnitude 9 Cascadia earthquake, revealed that the vast, sediment-filled basin under Seattle can magnify the type of ground shaking that puts high-rises at risk of collapse by a factor of two to five, which can trigger stronger surface effects than earthquakes in nearby California.
When rattled by an earthquake, the Times explained, the region's glacial-packed soils, which can extend more than four miles underground, violently shake and convulse, trapping massive seismic waves within the basin that underlies most of the city. Intense shaking like this could last for two minutes, which is four times longer than the average quake. While shorter buildings under 10 stories can withstand the earth's back-and-forth motion, tall buildings tend to whip back and forth under those conditions until they are on the verge of collapse.
As the Times reported, as a result of these findings, Seattle and its neighbor, Bellevue, plan on revising seismic construction standards for new buildings over 240 feet, or over 20 stories tall. These standards will require high-rises to be stronger and more sturdy than their predecessors, without the additional cost.
The plan to revise building codes has also raised concerns regarding Seattle’s older high-rises, many of which were constructed between the 1960s and 1990s, prior to when the dangers of earthquakes were fully understood. Older high-rises have a greater risk of major damage and collapse due to their fracture-prone welded joints, which are supposed to secure the steel frame, as well as their poorly-reinforced concrete supports. Seattle’s renowned Rainer Tower, for example, with its golf-tee-shaped base, was built in the 1970s and undoubtedly has fracture-prone welds. According to the study, buildings like that are up to five times more likely to collapse during an intense earthquake than a modern building.In Seattle, where the seismic threat to skyscrapers is higher than in California because of the city's sedimentary basin, there have still been no attempts to research and pinpoint dangerous high-rises. While the city is taking steps forward by enhancing construction standards, retrofitting old concrete and steel high-rises may be the next necessary step. This may prove costly, but taking time to fix the underlying structure of older buildings could prevent serious levels of damage that can be catastrophic to the community.