01
Houses from the 1970s and earlier
In the Tarzana ZIP code the median home was built in 1973, and about 78 percent of homes predate 1980. The 1970s are the largest single decade, and only about seven percent of homes went up in 2000 or later. Just under half are detached houses, and a little over half are owner occupied. Source: US Census Bureau, ACS 2024 5-year, table B25034, ZCTA 91356
With so little new construction, most Tarzana work is on houses and condos that are forty to seventy years old. That usually means the plumbing, electrical and windows come due at the same time as the finishes, and a full renovation is often the simplest way to do them in one pass. Doing them together also means one permit process for the rough work, not several.
Condo owners in Tarzana have one more step: the association's rules for noise, hours and access, which we read before any schedule is set.
02
Liquefaction zone, hills included
Every one of the eight Tarzana points we checked sits in a state liquefaction zone on the Canoga Park quadrangle, released in February 1998, and that includes points up Vanalden Avenue and Rosita Street, not just the flats near the boulevard. In our sample, the zone was the rule, not the exception.
For a typical house the state's soils report requirement does not apply: it exempts a single family frame home of up to two stories that is not part of a larger project. The City can still ask for one, especially for an addition or a second story, so we raise it with the reviewer early, because the answer can change the foundation and the budget.
If the house has a raised floor, the crawl space is part of that conversation, since it shows the foundation and the ground it sits on.
Sources: California Geological Survey, Seismic Hazard Zones, liquefaction layer, Canoga Park quadrangle 1998. California Geological Survey, Seismic Hazards Mapping Act overview
03
Two fire maps that disagree
The City of Los Angeles maps four of the Tarzana points we checked, including Wells Drive and upper Reseda Boulevard, inside its Very High fire hazard zone. CAL FIRE's 2025 map puts the same points in lower classes or outside the wildland classes entirely. The two maps do not line up here.
A city may add to the state's map but cannot lower it, so the City's own mapped zone is worth checking alongside the state's. For a Tarzana exterior project, we check both maps and plan for the stricter one. Replacement windows and vents are the usual place that difference shows up in the price, and we would rather show it on the estimate than at inspection.
Defensible space applies on the mapped streets as well, so planting and fencing near the walls are planned together with any exterior work.
Sources: City of Los Angeles, Very High Fire Hazard Severity Zones layer. Los Angeles Fire Department, 2025 CAL FIRE map recommendation
04
Hillside streets and where to start
Points on Vanalden Avenue, Rosita Street and upper Reseda Boulevard also sit inside the City's mapped hillside area, which brings its own hillside rules to an addition. Ventura Boulevard itself falls under a corridor specific plan, so a boulevard property gets an extra check before design.
For most Tarzana homes, the first project is a kitchen, a bath or a tile and shower update. Older tile often hides older waterproofing, so the shower is opened and checked before the new tile is chosen. We walk the house, check the hillside and fire maps for the parcel, and write the scope before any work begins. Source: City of Los Angeles, Hillside Ordinance area layer
If your street climbs toward the hills, mention it on the first call. That one detail changes which maps we pull and which rules the drawings follow.
