In November 2000, City Council approved changes to single-family home regulations and directed staff to develop Single Family Design Techniques to more specifically address some of the design issues with large additions and new homes. The goals of the new policies were to provide clear expectations regarding compatible home design, emphasize privacy issues and provide photos and illustrations of the majority of the policies.

On July 23, 2002, the City Council adopted the draft Single Family Design Techniques subject to minor changes and a request that staff provide the final version to the City Council as an information item. The changes result in minor language clarification. In addition, Council directed staff to review possible techniques relating to the privacy impacts of significant grade differences between properties (See Attachment A for a complete description of the final actions).

This report combines the Information Report requested by Council on the final Single-Family Design Techniques and the review of grade differences. Staff recommends approval of the proposed language addressing significant grade differences between properties as incorporated into the final Design Techniques.

City Council requested minor editorial changes (see Attachment A) to the Single Family Design Techniques. These changes have been made in the final document. City Council also directed staff to consider additional techniques to address privacy concerns when adjacent properties have significant grade differences.

Considerable time was spent during the Large Home study and the preparation of the Design Techniques to address the privacy impacts of second-story additions, but there are no design guidelines that specifically address privacy impacts of first story windows. For that reason, this analysis addresses first-floor additions and the potential privacy impact resulting from grade separations between properties.

Property Conditions:

Sunnyvale is a relatively flat community with no hills or valleys. Lots are frequently graded with a 6-8 inch drop between properties to achieve proper drainage and one-foot changes are not uncommon. However, grade changes greater than one foot between properties are relatively rare. Staff considers a difference of 18 inches or more a significant grade separation, which could impair privacy from single-story windows.

In most situations, a typical 6-foot high fence provides privacy screening between the first floor of one house and the yard and house of the adjacent property. Some neighbors agree to provide a 7-foot high fence (as measured from the highest adjoining grade), that further enhances privacy. Note that fences in general are not required between properties. (See Attachment C for an example of how fences and grade differences affect sightlines between yards).

If a new house is built with a high raised foundation, the new home could be afforded better visibility over fences into adjacent property. This can especially be an issue in Eichler neighborhoods, where the low-scale buildings are built on a slab foundation flush with grade level. Building plans indicate the proposed finished floor elevation and the elevation of the top of the curb. From this information staff could determine if there is a potential privacy impact.

Planning staff checks building permit plans for compliance with zoning regulations such as setback, coverage, and height. For new single-family homes or for additions greater than 20% of the original house (or for any second story addition) staff also conducts Design Review for compliance with the recently approved Single-Family Home Design Techniques. First floor additions are reviewed for architectural compatibility with the rest of the house but no analysis of the placement of windows (for the purpose of privacy review) is conducted. Site visits are conducted for all design review applications; privacy is only evaluated from the second floor. Field review will not always provide adequate information on adjacent property grades as staff cannot always look over fences and does not have permission to go onto adjacent properties.

The Building Division reviews grading plans for single-family homes and additions to assure adequate on-site drainage. A property may not drain onto an adjacent property; therefore no information concerning grades of adjacent properties is required. In order to have accurate information regarding differences in grade for adjacent properties, homeowners would need to submit grading plans that extend beyond their property. Typically, professional surveyors are needed to accurately determine the grades of the project site and surrounding properties; this practice would result in substantial additional expense to the property owner ($3,000-$5,000).

Issues:

• Expense to property owner to provide professional grading plans
• Number of properties which are affected by significant grade differentials
• Available methods of addressing privacy impacts on the first story
• Potential impacts to neighbors of requiring higher fences between properties

Staff is concerned with the possible expense of requiring grading plans for all Design Review submittals, especially as a small percentage of properties are affected by grade differentials of more than one foot in height. In addition, it would be difficult for staff to make accurate field assessments of grade differentials, as there is limited or no access to the rear yards of affected properties.

Staff also has concerns with requiring specific fence heights to address privacy impacts. Typically, because fences are optional, heights are determined by the preferences of the affected property owners. It could create conflict for staff to require higher fencing to address a perceived privacy impact that an adjoining neighbor may not want.

Staff does have review authority and control over the height of foundations. As explained in the Property Conditions section, a finished floor could be set 16-18 inches higher than that of adjoining properties due to raised foundation design. Staff recommends the following policy to address both privacy and bulk-related issues:

3.6G Finished floor elevations shall be consistent with the neighborhood character to minimize first-floor privacy impacts on adjacent properties.

Staff has evaluated a potential cost to publish 500 copies of the new Single Family Design Techniques. The cost would be about $13 per copy. The recently adopted fee resolution includes a nominal fee of $6.40 per copy for design guidelines. The remaining amount can be covered in the current operating budgets for Policy Planning and Development Services.

1. Adopt the design policies regarding privacy and differential grades as incorporated into the final Single-Family Design Techniques.
2. Adopt the design policies regarding privacy and differential grades with modifications.
3. Do not adopt the design policies regarding privacy and differential grades and direct staff as to further research.

Alternative 1.