COUNTY OF SAN MATEO

ENVIRONMENTAL SERVICES AGENCY

 
 

Date:

March 10, 2003

   

Set Time:

9:45 a.m.

   

Hearing Date:

March 25, 2003

 
 

To:

Honorable Board of Supervisors

 

From:

Marcia Raines, Director of Environmental Services

 

Subject:

Rural House Size Regulations

 
 

County File Number:

PLN 2002-00327

 
 

RECOMMENDATION

 

1.

Review and evaluate alternative approaches for regulating the size of houses in the rural Coastal Zone.

   

2.

Develop recommendations for consideration by the Planning Commission.

   

3.

Direct the Planning Commission to begin public hearings and formulate recommendations back to the Board of Supervisors.

   

PROPOSAL

 

Revisions to the County’s Zoning Regulations are proposed to control the size of houses in the rural Coastal Zone. Specifically, revisions are proposed for the Planned Agricultural (PAD) district and the Resource Management/Coastal Zone (RM/CZ) district.

 

BACKGROUND

 

Recently, Planning staff was directed to develop alternative methods of regulating house size in rural areas for consideration by your Board. Your Board, in turn, would then direct the Planning Commission to begin public hearings on the alternatives that would lead to a recommendation back to your Board.

 

Consideration of these regulations began in 2002 when staff developed for the Planning Commission a set of regulatory amendments to the Local Coastal Program (LCP) to reduce the permitted size of houses in the rural areas of the Coastal Zone. The Planning Commission held four hearings on the amendments: May 8, June 25, August 28, and September 25, 2002. At the September 25, 2002 meeting, the Planning Commission, based on information provided by staff and evidence presented at the hearing, voted to drop consideration of the amendments pending further analysis by staff. The Planning Commission voted to reschedule consideration and deliberation of the amendments to a future date.

 

DISCUSSION

 

Over the last couple of months, the Committee for Green Foothills and the Board of Realtors have developed alternatives to the amendments as proposed by staff. These two new alternatives and the original staff proposal are evaluated, compared, and contrasted in this report.

 

1.

Parcel Size Methodology: Size of House Determined by Size of Parcel (Original Staff Proposal)

     
 

This alternative would determine the size of house based on the size of the parcel. In other words, house to parcel size would be proportional. This is the traditional way for determining house size in many of the County’s zoning districts, except for those in the rural areas where there are no house size limitations.

     
 

a.

Advantages

     
   

This alternative is simple to understand and easy to calculate.

     
 

b.

Disadvantages

     
   

This alternative works well when parcel sizes are relatively small (less than one-half acre). For instance, in urban areas of the County where minimum parcel sizes range from 5,000 sq. ft. to 20,000 sq. ft., maximum house sizes range from 2,000 to 6,000 sq. ft., or roughly 30 to 40 percent of the parcel size.

     
   

In rural areas, the parcel sizes are generally significantly larger and range from five acres to hundreds of acres. If the same house to parcel size proportions were applied in these rural areas, a 20,000 sq. ft. house could conceivably be allowed on a 40-acre parcel and 36,000 sq. ft. house on an 80-acre parcel.

     
   

Therefore, a variation of this alternative would set a maximum limit on house size regardless of parcel size. This alternative caps house at 5,000 sq. ft. on parcels five acres or more.

     

2.

Density Credits Methodology: Size of House Determined by Number of Density Credits on Parcel

     
 

This alternative would determine the size of the house based on the number of density credits on a parcel. In the rural areas of the County, the zoning regulations allocate density credits to each parcel. The number of credits is determined by environmental conditions on the site (e.g., steep slopes, landslide susceptibility, etc.). Parcels ranging from 1-40 acres generate one density credit. Parcels ranging from 40-160 acres generate between 1 to 4 density credits, while parcels ranging from 160-320 acres generate between 2 to 8 density credits.

     
 

This alternative would allow a house size of 5,000 sq. ft. for each density credit.

     
 

a.

Advantages

     
   

This alternative is simple to understand and easy to calculate.

     
 

b.

Disadvantages

     
   

This alternative works well for large parcels over five acres. However, on small parcels it allows a relatively large house when compared to the other alternatives and other zoning districts in the County.

     

3.

Floor Area Ratio (FAR) Methodology: Size of House Determined by a Ratio of House Size to Parcel Size

     
 

This alternative would establish a ratio of parcel size to house size. The ratio would be 1:.5. Therefore, the maximum house size allowed would be one-half the size of the parcel. However, on parcels five acres or more, there would be no limit on house size.

     
 

a.

Advantages

     
   

This alternative is simple to understand and easy to calculate.

     
 

b.

Disadvantages

     
   

When compared to the other alternatives, this approach allows the largest house sizes when the parcels exceeds 15,000 sq. ft.

     
   

A variation of this alternative would cap house size at 10,000 sq. ft. on parcels 20,000 sq. ft. or more.

     

4.

Other Regulations

     
 

As mentioned, variations of Alternatives 1 and 3 would place maximum caps on house size. In addition, reducing the height of houses would not necessarily reduce size, but it would affect visibility in the landscape. Presently, house may be 36 feet high or three stories in rural areas. If house height were reduced to 28 feet or two stories, house size may or may not be reduced, but the bulk of houses certainly would.

     
 

Also, the enforcement of architectural standards on houses could be combined with any of the three alternatives. If new houses were to look like traditional farm or ranch style housing, they would perpetuate the traditional architecture of the rural Coastside and make it easier to achieve the overarching public objective of blending, melding, and harmonizing new houses with the natural environment around them.

     
 

In addition, extra restrictions in scenic corridors could be combined with any of the alternatives. In particular, houses in scenic corridors could be limited to 5,000 sq. ft. regardless of the number of density credits.

     

VISION ALIGNMENT

 

The regulation of house size in rural areas which helps harmonize new development in rural areas with the natural environment keeps the commitment of fixing a boundary between open space and development to protect the natural environment (Goal 13).

 

ATTACHMENTS

 

A.

Comparison of Permitted House Size by Alternative

B.

Types of Methodologies for Determining House Size

C.

Parcel Size Methodology

D.

Density Credits Methodology

E.

Floor Area Ratio Methodology