The Latest on Mercer Island's Residential Development Standards Update

March 20, 2017 | by Erin Sirianni

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The City of Mercer Island Planning Commission is in its final weeks of reviewing Mercer Island’s Residential Development Standards and will soon share their proposed updates with the Mercer Island City Council.
Here’s our brief background, the Planning Commission’s progress, and its likely proposed changes. If you’d like to make your voice heard before the Commission makes its recommendations to the City Council (scheduled for April 19th), be sure to attend April 5th public hearing – details below.
Background and Different Points of View
The review process of Mercer Island’s Residential Development Standards began approximately six months ago in October 2016, though discussions of a residential code review actually began about a year before that.  This effort has been controversial from the start, especially following a midnight proposal of a limited residential development moratorium at the City Council’s November 16th, 2015, meeting. (You can read about the “Residential Development Moratorium that Almost Was” in our Talk of the Town post here.)

“What we’ve heard” graphic from the Planning Commission’s Presentation at its February 25th Community Meeting

Though the moratorium was not enacted, the City Council prioritized the residential standards review on the City’s work plan for 2016-17. Since then and throughout the commission’s six-month review, strong and differing points of view have emerged within the Mercer Island community.
In brief, some community members are concerned that new home development is changing the character of Mercer Island neighborhoods, which they believe current residential code has failed to preserve.
However, other community members are concerned that a more restrictive code will impact their plans for building and home renovations as well as their property values when they decide to sell.  
Some builders, architects, and real estates agents have also weighed in on the debate, generally opposing the updates, especially in regard to tighter restrictions on home size.  
If you’d like to learn about the various arguments in more detail, read the Mercer Island Reporter recent article, “Mercer Islanders debate ‘neighborhood character’ versus property rights.”  The debate is also taking place on

Proposed Updates to the Residential Development Standards 

I had lunch last week with Alison VanGorp, Ombudsman and Administrative Services Manager with the City of Mercer Island’s Development Services Group (DSG), and we chatted about the commission’s progress and the changes that they have honed in on.  
She acknowledged that she has heard various positions from the community, and that the DSG and Planning Commission are still taking all input under consideration toward finalizing updates that align with the overall values of the Mercer Island community.
“We really want to stay away from dictating the design of homes,” she said. “But we also want to provide some relief to community members and provide some certainty about what can be built and how many trees will be protected.”
She shared that the commission is focusing on three areas of proposed change: 1) building and site design requirements; 2) tree and landscaping requirements; and 3) construction timelines, hours, and process.
I’ve summarized these proposed regulations below. They are also illustrated in the Planning Commission’s presentation shared during its February 25th Community Meeting.
Building and Site Design Requirements
The commission may recommend an 11% reduction in allowed gross floor area (GFA). GFA is the floor area of the house (including garage space) and excluding floor area below the ground surface (e.g. basement). The current GFA limit is 45%.  The proposed GFA is 40%. 
The graphics below show development variations based on the current code and proposed code using a 9,000 square foot lot example.
The commission may also recommend a GFA “cap” on home sizes for very large lots, based on zoning designation. The City’s reason for this proposed change is because 40% GFA on very large lots (e.g. >20,000 square feet) may result in out of scale homes.
Additionally, the commission is considering a daylight plane standard, which would require that the second story of a house be “set back” from the side property line, in order to reduce the “looming” of a large new house next door to an existing home.
Other building and site design changes may include creating greater side yard setbacks and eliminating impervious surface limits (since this standard doesn’t regulate house size).
Trees and Landscaping
The commission may recommend that 30% of trees be kept on lots for new homes, large remodels, and vacant land; tree permits to be required for removal of large trees; and 30% of front setback of homes will be required to be landscaped. The reason for this update is for improved tree retention & canopy coverage and to promote high quality vegetation for new homes.

Proposed Construction Hour Changes
The commission may recommend scaling back of residential construction hours.  The proposed hours are Monday through Friday, 7 am to 7 pm, Saturday, 9 am to 6 pm, and no construction will be allowed on Sundays and holidays. The reason for this change is to reduce construction impacts on neighbors and manage impacts in advance.
Construction Permit Changes
The commission may recommend that construction permits expire after 2 years; limiting renewals and extension to 1 year (total of 3 years to build); and requiring a construction management plan and schedule. The reason for this update is to reduce construction impacts on neighbors and manage impacts in advance.
The Planning Commission’s presentation from its February 25th, 2017, community meeting >>
The Planning Commission’s workshop boards from its February 25th, 2017, community meeting >>

Still time to weigh-in

Community members have an opportunity to provide additional input at an upcoming public hearing, to take place on April 5th, at 6 pm, at the Mercer Island Community & Event Center.
The Planning Commission is currently scheduled to share their recommendations with the City Council on April 19th.
What are your thoughts about the updates described above?  Please share in the comments!