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Green Code Conflict

Jun14 2011 // By: RESCUE GREEN // Categories: Sustainability No Comments

By: Bill Warkentin

 

The history and application of zoning codes until quite recently remained an evolutionary tale that began after the Chicago fire in 1909 and spread across the nation, big cities and small, dense urban areas and rural communities as well. The result is a century of antiquated, badly conceived and poorly written zoning codes. In particular, at least in Southern California, there are some significant gaps between current zoning law and sustainable development criteria, resulting in conflicts to designing and developing green buildings and communities. RESCUE Greens Bill Warkentin has studied this problem in some local jurisdictions and what follows are examples of discrepancies and conflicts between zoning codes and sustainable design criteria.

 

GENERAL CRITERIA: GENERAL PLANS AND ZONING, MIXED-USE AND PASSIVE COOLING

The almost universal adoption of single use General Plan categories implemented by similar zoning districts has contributed to our segregated and uninspiring land use patterns. Green development is a natural outgrowth of Smart Growth principles, which advocate the elimination of sprawl, propose compact and mixed-use development at higher densities, encourage walkable community centers, provide access to public transit, develop distributed parks, ensure safe walks to schools, and support conversion of the internal combustion engine to other, more sustainable means of powering transportation.

 

Very few jurisdictions currently have mixed-use districts and those that do have little to show in the way of built projects. Mixed-use districts require sufficient land to develop the variety of facilities, parking, open space and circulation in the proper relationships to make them work as primarily people places that also accommodate automobiles and truck traffic.

 

One of the most important sustainable principles is conservation of resources, i.e., making every resource stretch as far and serve as many purposes as possible. Unfortunately, many zoning and design codes do just the opposite: they enforce low density, wasting land and increasing pressure on outlying development; limit heights to two stories and restrict lot coverage mandating less than optimal housing size: force garages to the front making streets less than people friendly, penalize the use of porches by making them obey setback criteria thus effectively limiting the use of front yards and in some cases require turf and other water intensive ground covers in a drought stricken region.

 

Climatically, we live in a region that except for the mountains, requires a minimum of three times as much cooling as heating. That makes for some interesting demands on the envelope of the dwelling, especially if the architect desires to minimize or even eliminate mechanical air conditioning. Envelope design is the heart and soul of traditional green design, i.e., making the house skin perform optimally in terms of thermal transmissivity. Since we also live in an area of three or four years of drought for every year of above average rainfall, the use of water for natural evaporative cooling becomes problematic as do misters and water features yet these are passive cooling strategies that work well in our hot, arid environment.

 

Virtually all contemporary housing is designed for air conditioning, yet there are green alternatives that can substantially reduce or even eliminate mechanical assist. There are two aspects to this criteria, first, it is always more expensive and more difficult to remove heat from a structure than it is to keep it out in the first place and second, the more effective the envelope, the lower the demand will be on mechanically assisted air conditioning. The equipment may be downsized and the operating energy costs will be lower. Super effective envelopes can completely eliminate air conditioning.

 

Envelope design includes awnings, screens, fin walls, deeply recessed fenestration, cool roofs, arbors and trelliage, courts and patios, second floor decks over first floor windows, etc. Each of these should be accommodated in the zoning code but in most versions, setback criteria force the architect to sacrifice open space for green design features.

 

California recently adopted its own green building code, CalGreen, that places the state once again as the premier state in terms of energy efficient design and now has expanded energy concerns into the broader world of sustainable dwelling design, including site development, water conservation, waste treatment and storm water handling.

 

Impervious paving causes run-off that could otherwise be diverted to cisterns, percolated into the aquifer or used as irrigation water for landscaping. Many codes mandate pervious paving in direct conflict with water quality management plans whose BMPs are more aligned with sustainable design thinking.

 

Many codes do not permit greywater systems for irrigation or make the approval process so exhaustive, time-consuming, complex and expensive that no one in their right mind would take on the process.

 

SINGLE FAMILY DISTRICTS: MAXIMUM DENSITY, DEVELOPMENT STANDARDS AND GRANY FLATS

Infill projects should be allowed to achieve maximum densities, even receive bonus density for particularly good design solutions. Design criteria that define truly excellent design should include all aspects of sustainable development.

 

Avoid very large setbacks, particularly along arterial frontages that results in the planting of turf and other water intensive plantings. In some cases, turf is mandated with all that implies for a drought stricken region.

 

Another sticking point is design review functions in which neither the Planning Commission nor the staff are trained and experienced architects in sustainable design, resulting in arguments between licensed architects and unlicensed planners and others. In particular, the design of the building envelope for maximum thermal performance requires some interesting approaches that may not appeal to those with traditional taste e.g., thick walls, recessed fenestration, PV panels, etc.

 

Accessory units and granny flats make efficient use of available land without increasing the design of infrastructure, make efficient use of existing utility systems and do not burden open space and recreational facilities allocations. Increased residential densities make better use of land as a resource and of existing infrastructure. Increased densities also locate more potential consumers in clusters that can be served by mixed-use and compact neighborhood commercial developments.

 

Front yard setbacks frequently penalize the home owner by requiring the full setback for porches, patios and other private open space that serves both family and community purposes. A full side-to-side front porch 8’ deep pushes the home 8’ into the available backyard, substantially reducing usable private open space.

 

Lastly, some ordinances only permit snout houses, while prohibiting alleys and alley served garages, the use of which greatly improves the street scene, permits narrower street sections, reduces traffic on local streets and frees up front yard space for human use, not automobiles.

 

MULTI-FAMILY DISTRICTS: DENSITY, OPEN SPACE AND PARKING

Development regulations should permit achievement of the permitted underlying General Plan densities, bonuses and incentives notwithstanding. I know of several examples where open space, parking and height limits conspire to make maximum density all but impossible.

 

Private open space that exceeds the minimum requirement should be credited as a bonus against the requirement for common open space. Stacked balconies in multi-story construction offer shade to openings below, create private outdoor living areas and should be fully credited against the required private open space criteria.

 

Landscape criteria should be flexible and encourage shade plantings over turf and ground covers. Gray water irrigation systems should be permitted with appropriate health protections.

 

Requirements for large turf areas consume water and require high levels of maintenance. Since 70% of urban water is used on outdoor areas, smart landscape design is critically important. Turf areas primary ecological role is to replace indigenous landscape, consume excessive water and introduce pesticides and herbicides into the natural environment, none of which are on any list of good sustainable design criteria.

 

High density zones (anything over 20 du/ac) should permit as much of the required open space as can be developed to be located on green roofs and/or in hardscape areas such as play courts. Over 30 du/ac and the common open space requirement should taper off while the private open space requirement increases. The requirements for recreational amenities need to be refined so that improvements with high cost (enclosed structures, etc.) receive commensurate credit in meeting numerical criteria.

 

The code should recognize that over 30du/ac (very high density) podium development is likely to come into play, that this is a distinctly urban type of housing (or mixed-use) and green issues should take a lead role in design considerations. Urban densities should not be subject to the same open space requirements as more suburban housing types.  Urban dwellers have different expectations for recreation, travel and entertainment. As the Inland Empire becomes more urban, especially in the larger cities  (San Bernardino, Riverside, Rancho Cucamonga, Corona and some low desert cities in the Coachella Valley) we will see an increase in demand for urban housing and the amenities and features associated with these housing types, densities and lifestyles.

 

There is no particular justification for the zoning code to require highly technical improvements whose specifications change as technologies mature and best management practices evolve over time. An example is a specification for a 6’ base under pervious paving that may only require a 4’ base per manufacturers specs which requires the developer to file for a variance to modify the code regulation. This kind of prescriptive requirement ignores soil types, bearing capacity, percolation rates, soil depth and sub-surface drainage flows. Technical specs have no place in a zoning code.

 

PERFORMANCE STANDARDS VS. PRESCRIPTIVE CRITERIA

Sustainable design criteria are particularly susceptible to performance criteria and standards rather than prescriptive regulations. Prescriptive criteria always restrict design choices, often without really achieving the desired objective.

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