City of Los Angeles
Where Slope, Mass,
and Visibility Decide
What Gets Built
The Baseline Hillside Ordinance and the Baseline Mansionization Ordinance turn straightforward additions into review problems most owners do not see coming. Floor area limits change with slope band. Retaining walls change with setbacks. A project that complies on paper can still trigger discretionary review the moment it reads as too large for its block. We diagnose this before the first floor plan is drawn.
Service
Hillside & Mansionization Design
Service Area
City of Los Angeles — All Hillside Areas
Direct Line
The Problem
‘It’s Just an Addition’ Is
the First Mistake.
An owner buys a hillside property in the City of LA. The lot is steep but buildable. They want a second story, or a primary suite addition, or to convert the garage and add an ADU. The conversation with their first designer is short: yes, of course, here’s what we’ll draw.
Six months later, the project is stuck. The plans were drawn before anyone ran a slope-band analysis. The Residential Floor Area calculation came back smaller than the program assumed. The retaining wall alignment violates a setback that nobody flagged. The driveway gradient triggers fire access review. The visible mass from the street kicks the project into Baseline Mansionization scrutiny. None of these are unusual issues. They are the issues. And they all needed to be diagnosed before a single floor plan was committed to.
The Baseline Hillside Ordinance and the Baseline Mansionization Ordinance are designed to control bulk, slope impact, and neighborhood character on parcels that the City has determined are sensitive. They are not arbitrary. They are not optional. And they cannot be reverse-engineered from a finished design.
How We Approach It
Envelope Analysis Before Floor Plan
The order of operations matters more than the design itself. We do not draw a hillside project until we know what the parcel will hold. That order — envelope, then design, then documentation — is what separates a project that breezes through plan check from one that lives in correction cycles.
01
Slope-Band & RFA Diagnosis
We run the slope-band analysis and the Residential Floor Area calculation before the design starts. The owner gets a real number for what the lot allows, not a guess that has to be walked back later.
02
Retaining, Grading, Access
Retaining walls, grading limits, haul routes, and fire access roads are evaluated as part of the buildable envelope. Most failures we see in takeover projects came from treating these as afterthoughts.
03
Visible Mass Restraint
Even projects that comply numerically can trigger discretionary review when the visible massing reads wrong from the street. We design with the street view in mind, not just the floor plan.
Real Projects
What ‘Impossible’ Actually Looked Like
The phrase that brings owners to us is usually some version of another firm said it couldn’t be done. Sometimes the other firm was right. Often, the constraint was real but the reading of it was wrong.
Toe-of-Slope Retaining Wall Setback Compliance
Three prior consultants said the retaining wall setbacks on a sloped lot ruled out an ADU at the toe of the slope. The setbacks were real. The interpretation was not. The unit was approved as designed.
An Approval Another Designer Could Not Secure
A hillside project layered over a Specific Plan. The original designer could not navigate both at once. We restructured the approach and got the approval.
What This Page Does Not Promise
When the Maximum Envelope Is the Wrong Project.
Honest Counsel
Just because the lot will hold it does not mean it should. The largest project that complies is rarely the project that survives review without consequence.
Hillside owners often arrive with a square footage target. We respect that. We also tell the truth about it. On a sensitive parcel, designing to the maximum allowable envelope can attract scrutiny that a more restrained design would avoid — and the difference between approved and stalled is sometimes a few hundred square feet of restraint.
If a smaller, better-located, more carefully massed project is the right answer, we say so. The owner’s long-term interest is the project that gets built and the property that holds value. Not the project that maxes out a calculator.
Service Area
City of LA Hillside Areas
The Baseline Hillside Ordinance applies to a defined set of City of LA hillside areas. We work across all of them and we have run the diagnostics on enough parcels to know how each neighborhood’s conditions interact with the ordinance.
Mount Washington
Echo Park Hills
Silver Lake Hills
Hollywood Hills
Beachwood Canyon
Laurel Canyon
Sherman Oaks Hills
Studio City Hills
Bel Air / Beverly Crest
Brentwood Hills
Pacific Palisades Hills
Eagle Rock Hillside
Related Work
Where Else We Operate
Diagnose First
Hillside Project? Start With the Envelope.
Bring us in before the architect’s sketch becomes a contract document. A pre-design envelope analysis takes a fraction of the time a stalled correction cycle does — and it is the single best protection against a project that cannot be built as drawn.