Bob Melvey

Managing BrokerWindermere Real Estate

In-fill Housing

Side yard gardens are sprouting more than flowers these days due to several exceptions within the Seattle municipal code. These exceptions have allowed new homes to be built on undersized lots. The new homes are very popular among buyers because they offer modern amenities within an older established community. Many local residents are upset, however, because they feel the intrusion of modern architecture and loss of open space damage the character that people desire. Understanding the lot area exceptions within the municipal code won't stop the development, but it can at least help people adjust to the changes before they happen.

Much of the current in-fill housing has its roots in the past, when Seattle's neighborhoods were just getting started. It was very common for land to be platted with narrow 25 foot lots that were 100 feet deep. Usually, these lots were not purchased singly, but in bundles of two or more, being taxed as one parcel. The houses were built without any consideration of the original 25 foot lots, straddling two or more of them. Quite often though, the house would not straddle an end lot, leaving a spacious side yard.

The Seattle municipal code will recognize a side yard as a separate building site provided it meets certain criteria. Off street parking must be available for both the existing house and new building site. Also, the existing house must meet the side setback requirements that were in effect when it was built. The current setback requirement for a house is 5 feet, however prior to 1923 there were no setback requirements at all. This would make it possible for a new home to be only 5 feet from the original pre 1923 structure.

Another minimum lot area exception allows the creation of undersized building sites even if the area was platted with full size lots. A property may be subdivided provided it meets a test called the 75/80 rule. This rule requires that the square footage of these future lots be at least 75% of the minimum lot size required by local zoning. It also requires that the square footage of the new lots be at least 80% of the average lot area of the surrounding tax parcels on the same block face. Most Seattle neighborhoods have a minimum lot size of 5,000 square feet. Using the 75% ratio with this gives a minimum lot size of 3,750 square feet, so the original parcel must be at least 7,500 square feet to pass this first test.

Passing the second test is more difficult. In order for this 7,500 square foot lot to be sub dividable, the average lot size on the block face must be no more than 4,687 square feet. Since a subdivided lot is a new creation, the existing house must meet the current 5 foot side setback requirement regardless of its age. Through the use of a side setback easement it is still possible for the existing house to be closer to the new property line provided the new home is 10 feet away from the existing one.

The influx of people moving to Seattle has put side yards under increased scrutiny by builders and their agents. Having that new neighbor muscle in is not pleasant, but knowing about it in advance might help take the sting out of it.