Corte Madera adjusts rules for elevated homes in flood zone

Corte Madera has made it easier to raise parts of homes to protect them from flooding.

The Town Council voted unanimously to amend a related zoning ordinance at its meeting Wednesday night. The changes involve lot coverage allowances and setbacks for open decks, stairs and landings.

“Tweaking the zoning code may not have been on the work plan, but resilience is, like, top of the work plan and this is all about resilience,” Councilmember Eli Beckman said.

The regulations apply to homes in the “R-1 medium density residential district,” but some changes only apply to properties on Golden Hind Passage. More than a third of the parcels in Corte Madera are in the Federal Emergency Management Agency’s 100-year flood zone.

The changes are the latest in a years-long effort to give homeowners in flood zones more flexibility. In 2009, the town allowed raised homes an extra 2% in overall lot coverage for uncovered decks, and in 2024 exempted projects to raise homes from a design review process.

However, some barriers to raising homes remained. Decks more than 3 feet tall counted toward the lot coverage maximum, around 40%, for raised homes on lots more than 4,500 square feet in the district.

“Raising a home above the base flood elevation often elevates the home somewhere between 2 and 5 feet,” said Tracy Hegarty, a town planner. “New stairs and decks are often more than 3 feet in height after a home is raised, so lot coverage increases and oftentimes when a home is raised, homeowners are coming up on or exceeding the allowed lot coverage.”

The Town Council amended the rule to allow a total of 4% in extra lot coverage for uncovered decks, landings and stairs for raised homes, given that they don’t exceed the first floor’s height. This applies to all homes in the R-1 medium density residential zone.

Additionally, decks over 3 feet tall in the district had to follow a stricter setback requirement: Decks could only encroach the rear property line by 6 feet, versus as close as 5 feet from the property line if under 3 feet tall. Now, decks over 3 feet tall but no more than 5 feet tall fall under the same setback requirement as small decks — up to 5 feet from the rear property lines.

The setback regulation only applies to elevated homes on 93 bayfront properties on Golden Hind Passage. Hegarty said the area floods year-round, and yards sit lower than other areas in the flood zone.

“These properties experience flooding regularly, and as a result of their low-lying lots, their finished floor is commonly elevated higher above grade than other areas in the flood zone, which means that after finishing their homes, attached decks will be more than 3 feet in height in many cases,” Hegarty said.

While some homeowners elevate their homes voluntarily, others are required to when “substantial” home improvements are done, according to a staff report by Hegarty. Around 50 homes in town — mostly in the Mariner Village, Mariner Cove and Golden Hind Passage areas — have been raised above the base flood elevation so far, Hegarty said.

The zoning changes were prompted by an application from a homeowner on Golden Hind Passage who wanted to raise a home and deck. This brought forward something staff “missed” in previous ordinance updates, although the area is unique in its elevation needs, according to Amy Lyle, the community development director.

“Because of the flooding, their entire backyards are unusable, unlike other areas of town,” Lyle said.