Safe Healthy Spaces

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There are well-documented and practical ways to design and build safer, healthier spaces in mixed-use neighborhoods. For implementation at 5 different scales, this report presents essential design features, benefits, challenges and successful examples, and provides resources with more information. Benefits to residents include an enhanced sense of safety, belonging, and neighborliness, as well as improved health and wellbeing.

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Safe Healthy Spaces

  1. 1. Creating Safer, Healthier Spaces in Mixed-Use Neighborhoods Levin Nock Ph.D., Sustainable Building Advisor 2008 Copyleft CC-BY v2.0 www.GreenWayNeighborhoods.net levin100 AT levinnock.com Summary: There are well-documented and practical ways to design and build safer, healthier spaces in mixed-use neighborhoods. For implementation at each of several scales, this report presents essential design features, benefits, challenges and successful examples, and provides resources with more information. Benefits to residents include an enhanced sense of safety, belonging, and neighborliness, as well as improved health and wellbeing. Scope: This report was prepared and made available pro bono, with the hopes that readers interested in good design will find the information helpful. It is based in the Pacific Northwest region of the USA. It might provide a useful starting point for design work in other regions, but some aspects would need to be re-evaluated. It’s a work in progress, not intended to be complete. Readers are responsible for using this information with their own judgement, at their own risk. If you would like to receive or provide more details for any of the topics mentioned, please contact me. Contents 1 Each Unit Built Green............................................................................................................. 2 1.1 Design Features .............................................................................................................. 2 1.2 Benefits .......................................................................................................................... 3 1.3 Challenges...................................................................................................................... 3 1.4 Examples........................................................................................................................ 4 1.5 Resources ....................................................................................................................... 4 2 Shared, Semi-Private Pocket Parks.......................................................................................... 4 2.1 Design Features .............................................................................................................. 4 2.2 Benefits .......................................................................................................................... 5 2.3 Challenges...................................................................................................................... 5 2.4 Examples........................................................................................................................ 6 2.5 Resources ....................................................................................................................... 6 3 Neighborhood with contiguous greenway network .................................................................. 7 3.1 Design Features .............................................................................................................. 7 3.2 Benefits .......................................................................................................................... 7 3.3 Challenges...................................................................................................................... 8 3.4 Examples........................................................................................................................ 8 3.5 Resources ....................................................................................................................... 9 4 Community: Group of neighborhoods around a central business district .................................. 9 4.1 Design features............................................................................................................... 9 4.2 Challenges.................................................................................................................... 10 4.3 Examples...................................................................................................................... 10 5 Cities with slow traffic separated from fast traffic in 2 separate, dedicated networks.............. 11 Safer, Healthier Spaces Levin Nock p. 1 of 11
  2. 2. 1 Each Unit Built Green 1.1 Design Features 1.1.1 Solar Access (temperate climate zones, Northern hemisphere) • Each unit should have some exterior walls on the north and south sides. Glazing on the north and south walls of each unit, and possibly north-facing clerestories, provides even daylighting throughout the day. • Any glazing on the east and west is carefully considered, such as an east window in the breakfast nook to catch the morning sun. Any west-facing windows are kept small to minimize the late-afternoon glare and summer heat gain that large west-facing glazing would create. • Overhangs such as eaves, porches, upper-story decks and trellises above south-facing windows limit the summer heat gain. Also low-e coatings, on windows where overhangs are not practical. • A substantial part of the roof faces approximately south. Each unit can have south-facing domestic hot water panels and PV panels, and north-facing monitors or clerestories for daylight (possibly with controllable openings for passive solar cooling). With careful design of the roof, each unit will have its own usable solar exposure, with minimal shading from neighboring units. The roof should have ridge-lines on an east-west axis, to provide large south-facing slopes for solar appliances, and north-facing clerestories for even daylight without heat gain. • Whether or not the new units are built with PV arrays and solar domestic hot water panels, they should be designed and built with conduits to carry plumbing and wires from the roof to the utility area, so that solar utilities can be easily added later. • Trees planted on the south and southwest sides of buildings should be short enough, at maturity, not to block the solar access of the roof. • While daylighting is specific to each unit, solar heat and electricity can be shared. An alternative to the per-unit requirements above, would be to provide district-level solar power generated on the roof of a nearby school or commercial building. 1.1.2 Water catchment When the footings are poured for a new building, it is relatively easy to dig space for a large catchment tank, for water. This could be as simple as a large impermeable bladder contained under a porch, or in the corner of a basement. If the space is available, and the roof is made of metal or other suitable material, then residents can choose whether to add a complete water catchment system. 1.1.3 Sprinkler fire prevention Interior water sprinklers can be installed cost-effectively by the plumbers who subcontract the conventional plumbing. If every unit has a sprinkler system for fire prevention, then some fire departments are more cooperative about permitting narrow streets. Narrow streets are essential to maximize the land area that’s available for greenspace and for buildings. Also, with more and more research by Sightline.org and others documenting the hazards of common fire retardants, the future contents of residential homes might be more flammable than they are today. Safer, Healthier Spaces Levin Nock p. 2 of 11
  3. 3. 1.1.4 Visitability • One zero-step entrance, at the front, back or side of the house • All main floor doors, including bathrooms, with at least 32 inches of clear passage space • At least a half bath, preferably a full bath, on the main floor. • Basic requirement for all units, with a few exceptions as needed for difficult sites. 1.1.5 Greenbuilding systems Earth Advantage Platinum www.earthadvantage.com (Pacific Northwest) BuiltGreen (various state and local programs) LEED for Homes pilot https://www.usgbc.org/DisplayPage.aspx?CMSPageID=147 In a Net Zero Energy building, over a year’s time, the building produces as much energy as it consumes. While this goal is not yet as systematic and commonplace as the Earth Advantage system, there are significant local examples proving that it’s possible. One of the most systematic versions of this idea is the “Passive House” movement in Germany. One of the simplest ideas to borrow from this movement, is that the ratio of exterior surface area to interior volume should be minimized, typically by building multifamily units rather than single family residences. Living Building Challenge, Cascadia Greenbuilding Council. www.livingbuilding.org 1.2 Benefits Lower and more predictable utility bills, for as long as the house stands. Greater comfort and safety during utility outages. Residents are healthier, from breathing cleaner air indoors. Marketing opportunities Guarantee to pay the difference if the monthly heating bill exceeds a limit within the period of the home warranty. Portland-area RMLS will list green features of new homes, starting in 2007. 1.3 Challenges 1.3.1 Solar Some mortgage programs such as FHA require that a home be aligned with the street. Thus, unless the streets are straight lines on north-south or east-west axes, it may be difficult to design a south- facing roof. In Village Homes (VH), all houses have a south-facing roof, the streets have gentle curves, and the houses were financed using non-FHA mortgage sources. Most VH houses have a private, fenced patio facing the street; the house might not be lined up parallel with the patio fence. The good news in Oregon is that solar appliances with grid-tied PV still work pretty well, on an annual basis, as long as the roof does not face north. While due-south is best, a street can follow a gentle curve, with houses facing the street, and all houses can still have a roof that faces roughly south. Safer, Healthier Spaces Levin Nock p. 3 of 11
  4. 4. 1.4 Examples In Village Homes, all units have a south-facing roof. CC&R’s (Covenants, Conditions and Restrictions) define the “solar rights” of each unit, so that an adjacent unit cannot block a neighbor’s solar access. Canada is working on new building code that could eventually make it illegal to build anything less than a Net Zero building. German “Passive house” program http://en.wikipedia.org/wiki/Passive_house Solar domestic hot water and PV in Oregon: http://www.oregonseia.org/ 1.4.1 Local Portland, Oregon Net Zero Energy examples include Blueberry Lane spec homes in NE Portland by developer Billy Reed, website has extensive design details: http://www.villagegreenhomes.org/ Nathan Good designed Net Zero Cannon Beach home: 2268 sf, 3 bd/2.5 bath, Rich Elstrom Construction. www.nathangoodarchitect.com/publications/article_pdfs/fhb_feb06.pdf Tom Kelly’s house in Parkdale, OR designed by Liz Olberding, built by Neil Kelly construction. http://www.earthadvantage.com/news/item/?key=20 Green Hammer recently built 2 residences. http://www.theleapfroghouse.com The Rose house, designed by SERA Architects and built by Coho Construction is a local example of an Accessory Dwelling Unit. http://www.oregon.gov/ENERGY/CONS/RES/tax/docs/RoseHouse.pdf Construction options for the walls of Net Zero homes include insulated rammed earth, Structural Insulated Panels (SIP), advanced framing (Larson trusses or staggered 2x4’s on 8” or 10” sill plates) with sprayed-in insulation, insulated concrete forms (ICF), strawbale, and conventional 2x6 walls with an exterior layer of sealed, taped foamboard sheathing. The basic goal is to make thick walls with high R-values and no air leaks. While cob and light-straw methods can also accomplish this goal, they are too labor-intensive for most professional contractors to accomplish profitably. However, Joshua Klyber is exploring ways that modern German methods of earthen construction can be adapted to the Pacific NW cost-effectively. 1.5 Resources Visitability: www.concretechange.org 2 Shared, Semi-Private Pocket Parks 2.1 Design Features 1) Clear sense of semi-private shared space Bounded by surrounding units. Clearly delineated entry points from the public street or sidewalk. In an urban setting, entry points might be tall, locked gates to which all residents have a key. In a suburban setting, Safer, Healthier Spaces Levin Nock p. 4 of 11
  5. 5. while the entry points might not be locked, a visitor still has a clear sense of entering private property. 2) Human scale dimensions height to width ~1:6 Example: St Francis Park h/w ratio is 1:6, 150 ft x 150 ft, flanked by trees & 3-story apartments of roughly 25 ft height 3) All or almost all units have a view into the common space that the units surround. Children can play safely, without dedicated adult supervision. Neighbors notice activity and take ownership to keep the area safe. 4) High quality layout and landscaping Trees (especially trees close to the perimeter buildings) attract people, promote neighborhood social ties, reduce crime, and help people feel safer. For children: play equipment, paths for wheeled vehicles, areas for exploratory play, etc. For adults: movable chairs & tables to fit the activities of each new day. 5) Each unit has private outdoor space clearly distinguished from the shared space, such as: Fenced balcony or patio between unit and park Small private garden between unit and park Porch or fenced private patio on the streetside 6) Clear boundaries and easy access between what is private (dwelling unit, patio, small private yard) and what is shared. (adapted from Clare Cooper Marcus, Professor Emerita in Architecture and in Landscape Architecture, UC Berkeley) 2.2 Benefits These features help people feel safe and at home in their neighborhood. This is a smaller scale than the public life of streets and typical public parks. The presence of these features means that children can play outdoors safely, conveniently and often. This is especially important when 40% of elementary schools nationally have either eliminated or shortened outdoor recess, and working parents have a limited amount of time to dedicate completely to supervised play at a distant park. “In a series of large-scale, highly controlled field studies,… Trees and grass cover were linked with greater use of residential outdoor spaces by adults and children, healthier patterns of children’s outdoor activity, more social interaction among adults, healthier patterns of adult–child interaction and supervision, stronger social ties and greater resource sharing among adult residents, greater sense of safety and adjustment, lower levels of graffiti and other signs of social disorder, fewer property crimes, and fewer violent crimes… “One striking implication of this body of work is that the location of trees matters at a surprisingly fine-grained scale. Participants in these studies all have ready access to neighborhood green spaces and live within a few miles of one of the most extensive examples of urban nature in North America… Further, the participants in each study live within the same neighborhood, with the same overall level of tree canopy. Yet in study after study, the finding is that having trees directly outside one’s own building is different than having those same trees just outside neighborhood buildings. To fully reap the social benefits of trees then, the urban forest may need to be substantially more tightly integrated into the residential urban fabric than is currently recommended.” (Kuo 2003) 2.3 Challenges Many housing developments have common greenspace areas that have become neglected, unmaintained, dangerous eyesores, because they lack one or more of the design features outlined Safer, Healthier Spaces Levin Nock p. 5 of 11
  6. 6. above. In areas where new residents have incorporated all of these features (such as Montgomery Park in Boston’s South End), the common areas have been transformed from eyesores into delightful amenities. If a well-meaning city planner or other stakeholder claims that common greenspace is difficult to maintain, and cites an example, then this provides an excellent opportunity to explore which feature(s) are missing from that particular example. 2.4 Examples 2.4.1 City blocks, with a central shared green in the middle. St. Francis Square in San Francisco Southside Park cohousing in Sacramento On Going Commons in Portland The Meadows in Berkeley Greenwich Millenium Village in London (central green roof/park over 2-story parking garage) London’s Victorian garden squares MacDougal-Sullivan Gardens and Turtle Bay Gardens in New York City “Vault Field of Dreams Ad” http://video.google.com/videoplay?docid=3696564454881273741 2.4.2 European “woonerf” neighborhoods in northern Europe. Narrow, one-way street loops around a central green, with only one entrance/exit point. Pedestrians share the pavement with cars. For instance, Cherry Hill, 29 unit affordable housing townhouses in Petaluma CA, built 1992. 22-ft wide one-way access road with speed bumps around a central green. No through traffic. 4 paved courtyards off the loop. No sidewalks—traffic is limited and slow so that pedestrians and cars share the streets safely. 2.5 Resources www.CommunityGreens.org Clare Cooper Marcus, “Shared Outdoor Space and Community Life”, ‘Places’ 15(2) pp32-41. http://repositories.cdlib.org/cgi/viewcontent.cgi?article=1813&context=ced/places Clare Cooper Marcus and Wendy Sarkissian, “Housing as if People Mattered”, 1986. Anne Kristin Morris (2002) “Planning for Community Greens in City Neighborhoods”, Masters Paper, Dept of City and Regional Planning, University of North Carolina at Chapel Hill. www.communitygreens.org/Resources/AnneMorrisThesis.doc Frances E. Kuo (2003) “THE ROLE OF ARBORICULTURE IN A HEALTHY SOCIAL ECOLOGY”, Journal of Arboriculture 29(3):148-155, May http://treelink.org/joa/2003/may/04Kuo.pdf Oscar Newman (1996) Creating Defensible Space http://www.huduser.org/publications/pubasst/defensib.html Safer, Healthier Spaces Levin Nock p. 6 of 11
  7. 7. 3 Neighborhood with contiguous greenway network 3.1 Design Features 3.1.1 Contiguous Greenways 1) ~500 residents share one neighborhood with one contiguous network of greenway paths 2) All residents can walk/wheelchair/bike from their home to the village center without crossing the street, in less than 10 minutes. In most cases, 5 minutes or less (1/4 mile). 3) Eliminate most (preferably all) pathway/street intersections, using cul-de-sacs 4) Pathways in pleasant greenspace, not beside roads 5) Collect the greenspace in useful units, and minimize pavement 6) Most residents can walk downtown in a fairly direct path, with minimal doubling back or zigzagging. 7) Every unit is accessible by a pathway on one side and by a road on the other side. a. In some developments, the front door faces the greenspace. Guest parking lots provide access to the greenspace, and guests approach the front door through the greenspace b. In other developments, the front door faces the street, and the backdoor faces the greenspace. 8) Natural drainage a. Narrow, curbless roads along ridges that are the highest elevation in the area b. Permeable concrete for neighborhood streets: regular concrete mix, without sand c. Stormwater is managed on the surface, in either flowing streams, ponds, or bioswales. Plan: any water standing for more than 2 days will be a permanent water feature, with fish to eat mosquitoes. Or it’s a seasonal pond that dries up in the summer, with native Oregon frogs. d. Where feasible, follow existing topographic contours, preserving existing streambeds e. Pathways follow close to the streambeds/bioswales, with small bridges or culverts as necessary f. Most stormwater on the road drains directly down through the permeable pavement. Any water that drains off the road, flows around the buildings to the network of bioswales and streams. g. Water from some rooftops may flow into a cistern, for use by residents. Any remaining stormwater from rooftops will flow around the buildings and into the network of bioswales and streams. 3.1.2 Shared heat source Ground source heat pump Steam plant with cogenerated waste heat from commercial/industrial district Solar thermal hot water on a neighborhood scale 3.1.3 Shared commercial space The neighborhood center can have office space for local businesses and telecommuters. 3.2 Benefits A contiguous greenway network with surface management of stormwater provides an attractive amenity, while eliminating the cost of stormdrains. Safer, Healthier Spaces Levin Nock p. 7 of 11
  8. 8. In Oregon, creating a condominium can save up to 1 year for permits, compared to a subdivision. If the principal of an elementary school is expected to know the names of all the students, then the school cannot hold more than 500 students. 500 people is a good number for a group. In Village Homes, with less than 1000 residents, the residents know, on average, 40 neighbors and have 3 or 4 close friends in the neighborhood. In a nearby standard subdivision, residents know 17 neighbors on average and have one friend in the neighborhood. Permeable concrete: concrete is more durable than asphalt, and with the rising cost of petroleum, the cost is comparable. The light color of concrete reduces the summer urban heat island effect. The City of Portland is experimenting with permeable concrete on a section of Going street. While permeable concrete is not quite as durable as regular concrete with sand, it is suitable for residential streets (probably not for arterials). Stormwater runoff is a major environmental impact of development, and permeable concrete pavement can help mitigate this impact. 3.3 Challenges 3.3.1 Regulatory changes that would help Narrow streets Minimal, flexible setbacks Mixed-use zoning Cluster development No curbs Pathways in lieu of sidewalks Stormwater as surface water Water catchment and greywater reuse permitted “Smart Code” is an improvement over most existing local codes, but is based on a system of connected streets with adjacent sidewalks. This code will need to be modified, to support a network of paths that are not necessarily adjacent to roads. 3.4 Examples Village Homes, Davis CA Radburn, NJ 3.4.1 Shared Commercial Space: Village Homes Village Homes, a subdivision with fewer than 1000 residents surrounded by residential subdivisions, has a community center with a swimming pool, children’s playground, one restaurant and offices. There is usually a waiting list for office space, from residents who want to work close to home. While the commercial district is very small and quiet, with no retail component, it is an important amenity for the community. The community ownership of this property is discussed in more detail below, based on an interview with Judy Corbett, one of the founders. The commercial property in the town center is owned by a for-profit corporation. This corporation is managed by a committee of the Village Homes Homeowners Assoc (VH HOA). All the profits from the corporation go to the non-profit VH HOA. Safer, Healthier Spaces Levin Nock p. 8 of 11
  9. 9. All residents in the neighborhood pay homeowners dues, for instance, for maintenance of the landscape and the common property (commercial, community center/pool, etc.). A significant amount of this money is for 3 gardeners who tend the orchards and other agricultural components. The developers originally hoped that the agriculture and edible landscape might pay for itself directly as quot;community supported agriculturequot;, but this has not happened. The Homeowners' dues are much smaller than they would be, if there were no commercial property. Nobody receives dividends—the residents simply pay lower Homeowners dues than they would otherwise. Legal challenges: 1) A non-profit must be careful about doing commercial work. 2) Most homebuyers are not SEC qualified investors, so they need to buy a home without exactly buying a share of a private, for-profit corporation. A very smart lawyer spent significant effort to set up the legal structure properly. If the commercial property generated income in excess of all the neighborhood expenses, then a different legal structure might be required. 3.5 Resources www.GreenWayNeighborhoods.net Designing Sustainable Communities: Learning from Village Homes, by Judy Corbett and Michael Corbett., 1999. Human Scale, by Kirkpatrick Sale. 1980, Reprinted 2007. 4 Community: Group of neighborhoods around a central business district 4.1 Design features • All residents can walk/wheelchair/bike from their home to the town center in less than 10 minutes. This is measured along each actual travel path, not a theoretical radius from the center. • Eliminate as many pathway/street intersections as feasible, and mitigate any remaining intersections with traffic lights, tunnels or bridges. • Pathways in pleasant greenspace, not beside roads • Group enough neighborhoods together, and provide enough through-traffic, to support a vibrant central business district • Shared local schools. Elementary, Middle, and High Schools are all available to students under their own power. For elementary schools, this means a very short walk or bike ride along very safe pathways. High school students can bike farther to a more centralized location, but they still need safe pathways. • Principles for Walkable Communities • Ahwahnee Principles, Local Government Commission • 10 Principles for Smart Growth, Urban Land Institute • Charter of the New Urbanism, Congress for the New Urbanism • Principles of Smart Growth, Smart Growth Network • LEED-ND (Neighborhood Development), United States Green Building Council • Patrick Condon’s Principles for Walkability Safer, Healthier Spaces Levin Nock p. 9 of 11
  10. 10. 4.2 Challenges If each neighborhood has 500 to 600 residents, then a thriving business district will need at least 4 to 8 of these neighborhoods surrounding it for pedestrian traffic, plus additional customers who bike or drive or take the bus from more distant neighborhoods. Each small neighborhood should have its commercial “center” directly adjacent to the business center of the town. Comparison data on purchasing power, business activity, and workforce density for all census tracts, residential ZIP codes, and the 100 largest metro areas in the U.S. is available here: http://www.uwm.edu/Dept/ETI/PurchasingPower/purchasing.htm Another free resource is www.esribis.com, with profiles of any community based on zip codes. Suburban retail centers tend to engage in a winner-takes-all size war, where the largest regional shopping center on the largest road attracts all the customers, leaving smaller retail outlets with fewer and fewer customers. http://www.walkablestreets.com/box.htm In order to maintain a viable commercial center in a suburban region, it is important to manage this dynamic successfully. One goal is to attract the business of local resident constomers. Walkable distances along pleasant pathways to pedestrian-oriented storefronts can help with this goal. Another goal is to somehow attract consumers from a greater distance, without necessarily having the biggest “big box” on the largest road in the region. Some businesses require a large number of potential customers, even if they have a “local” flavor. For instance, a single “Curves” franchise (small neighborhood fitness center for women) needs a population base of ~10,000 people. 4.3 Examples 4.3.1 Future I have yet to find good examples of clusters of 500-person groups, with each group defined by clear physical boundaries. Most urban planning involves groups of 2000 or more people with vague, fluid boundaries, so the social benefits of small groups are lost. Village Homes and Radburn, NJ are surrounded by more conventional suburban development. In an urban setting, a single building can easily hold 500 residents. Somewhere, there are probably midrise urban developments where each residential building has central courtyard space(s) meeting the guidelines from St Francis Square, each residential building is within easy walking distance of a commercial core with businesses and schools, and residents love living there. If you know of any examples, please email me a note, levin100 AT levinnock.com. Thanks. 4.3.2 Issaquah Highlands Issaquah Highlands in Issaquah, WA will have a population of 10,000 at build-out, which should support a thriving commercial district at the main entrance to the development. Most of the residents will drive through the commercial district in their daily commutes, but relatively few residents live close enough, or have an inviting path, to walk downtown. Each neighborhood has ~2000 residents. 4.3.3 Orenco Station Orenco Station in Hillsboro, OR has a popular grocery store and a Starbucks to anchor its commercial district, and a busy arterial to supply plenty of regional traffic. http://www.tndwest.com/orencostation.html Safer, Healthier Spaces Levin Nock p. 10 of 11
  11. 11. While the original residential development is not really in walking distance of the Max stop, new apartments, townhomes and condos are filling in the high-density area immediately around the Max stop. 4.3.4 Ladera Ranch Future research. www.laderaranch.com 4.3.5 Victorian green blocks in London Future research. 5 Cities with slow traffic separated from fast traffic in 2 separate, dedicated networks City Population (approx) Midway City, UT, USA 2,000 Houten, Netherlands 40,000 Davis, CA, USA 60,000 Reston, VA, USA 60,000 Almere, Netherlands 150,000 Venice, Italy 275,000 (1M in the summer) Calgary, Canada 1,000,000 (limited slow traffic network) Safer, Healthier Spaces Levin Nock p. 11 of 11

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