ADU Construction in Westlake Village
Serving 91361 · 91362 and Thousand Oaks, Agoura Hills, Oak Park
An ADU in Westlake Village sits at an interesting intersection: state and county rules that have made second dwellings far more achievable, and a planned community with strong expectations about how buildings look from the street and the water. Lots vary enormously between the neighbourhoods, from compact planned parcels to substantial hillside sites, so the honest first conversation is about this particular property rather than about ADUs in general.
Real projects. Real prices.
73 finished remodels published with their final price — nothing hidden.
What our finished LA work actually cost: 27 kitchens ran $23k–$84k, median $50k; 28 bathrooms $28k–$105k, median $38k; 17 whole-home remodels $36k–$440k, median $150k. Real final prices from our own job records, not estimates.
$33,000 A backlit mirror over a double vanity, with stone-look tile and matte black fittings throughout.
$38,000 Emerald shaker cabinetry and brass hardware around a cream range and an apron sink.
$75,000 Wood shaker cabinetry under a full-height quartz slab, with a marble-look hall bath.
$95,000 Two glazed-tile showers, one olive and one aqua, with brass fittings and taupe shaker vanities.
$238,000 A walnut-fronted quartz island, arched openings, and sage-green stacked tile baths.
$275,000 A broad quartz island, a curved staircase with iron balusters, marble-look baths.
Second dwellings in a planned community
Which neighbourhood, which lot, which rules
The community is not uniform. What is straightforward on a large hillside parcel may be genuinely constrained on a compact lakeside lot with an active association. Establishing the specific position of your property is the first hour of work and it saves the most.
Designing a building that belongs to the plan
A second structure here should read as part of the property, not as an addition to it: rooflines that relate to the main house, materials that match, and landscape that ties the two together. That is what makes an ADU pass review comfortably and look right for the next thirty years.
Applications through EPIC-LA
Because the City contracts building and safety to the County, an ADU application follows the County's process and its documentation standards. A complete package — site plan, utilities, structure, energy — moves through that system markedly faster than a partial one.
Connecting a new building to an old one
The main house's panel, water service and sewer connection were sized for a single dwelling decades ago. Verifying their capacity, and pricing the runs across the site honestly, keeps the project's least visible cost from becoming its biggest surprise.
The elevation the water can see
On the neighbourhoods around the lake, a property has a second public face that most houses never have: the side visible from the water and from the paths and homes across it. A new building placed with only the street elevation in mind can present a blank flank to that view, which serves nobody. Designing all sides of a second dwelling as though each is a front — considered fenestration, materials that continue around the corner, roof forms that read well from a distance — is what makes an ADU here sit comfortably in a community whose whole plan is organised around water and open space.
Written by Onn Cohen-Meguri, founder and designer at Design Onn Point — 12+ years in business, 1,200+ finished Los Angeles projects. CSLB #1133368.
Pricing in Westlake Village
Market estimate, not our own project data.
Talk to Onn about your Westlake Village adu construction.
Free consult, no obligation. Onn reads every inquiry personally — and aims to reply within one business day.
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