Mansionization: How Big is Too Big?

If you live in LA, you have perhaps heard the terms “Mansionization” and “McMansion” which refer to the unfortunate temptation some property owners feel to build out their parcels from property line to property line without any dimensional “quiet spaces” or landscaping. Because poor design on one lot can impact a neighborhood as a whole, communities create ordinances in order to keep a lid on the ridiculous, and to protect daily quality of life, neighborhood ambiance, and property values.

The Los Angeles Baseline Mansionization Ordinance is the governing document that determines how large a residence can be built on a single family lot.  These guidelines apply primarily to non-hillside and non-coastline properties (for instance, Brentwood is included in this ordinance in its flat parts, but not north of Sunset — where it becomes hilly).

Of course, you don’t want to make any building decisions based on this blog post. For accurate and current information, I strongly suggest that you contact the Los Angeles Building and Safety Department where you can access all kinds of interesting information on permits, code enforcement, zoning, inspection, etc.  Generally, however, the areas of a residence which often are included towards square footage are:

~  Area within exterior walls of all structures on a lot, except as stated below. Clarification : This area does not include the actual thickness of the walls.

~  Portions of the building, in excess of 100 sq-ft, with ceiling height greater than 14 ft shall count as twice the area.

~  Any attic, or portion thereof, with ceiling height more than 7 ft.

The following are often not included towards the total square footage for a lot:

~  First 400 sq-ft, of covered parking area.

~  Detached accessory buildings, no greater than 200 sq-ft; the total combined area no to exceed 400 sq-ft.  Clarification: When a detached accessory building exceeds 200 sq-ft, the area of the entire structure shall be counted; in other words a structure that is 250 sq-ft will count as 250 sq-ft of Residential Floor Area. Clarification: Detached covered parking is not subject to this 200 sq-ft limit, but is calculated as detailed above.

~  First 250 sq-ft, of porches, patios, and breeze-ways with a solid roof open on at least 2 sides

~  Area of stairwells shall only be counted once.

~  Porches, patios, and breeze-ways that have an open lattice roof.

~  Basements when the elevation of the upper surface of the floor or roof above does not exceed 2 ft in height above the finished or natural grade, whichever is lower.

Not all Los Angeles properties are governed by the Baseline Mansionization Ordinance and there are overlay maps available to determine a specific property inclusion.  Most properties are eligible for additional maximum square foot allocations if they adhere to specific set back and offset requirements.

Do you have an opinion on how wide or tall a home should be in your neighborhood? How big is too big?  Leave your comments!