







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateTrusted Room Addition Contractor for Woodland Hills Homeowners
Adding a room in Woodland Hills is rarely just about square footage. It’s about making a house work for the people in it, without starting a project that stalls, drains the budget, or leaves a permit board blank at the curb. That’s where we come in. Fielding ADU Woodland Hills is a Room Addition Contractor - Woodland Hills that builds by The Garrison Code: show up in the window, price in writing, by the book, leave it clean, stand behind it for a year. Led by Reed Calloway, our crews have built room additions across Woodland Hills since we opened as part of the Garrison Partners family, which has held itself to The Garrison Standard since 2006. Call (559) 254-0116 and you will reach a live person, not a voicemail.
Sunroom Builders

Sunroom Builders handle the kind of room addition that brings daylight in without the cost or complexity of a full foundation-and-framing addition. In Woodland Hills, where summer heat runs long and winter days stay mild, a sunroom is often the most practical way to add a breakfast room, a reading space, or a plant room that actually gets used. Fielding ADU Woodland Hills designs and builds sunrooms as real conditioned rooms or three-season spaces, depending on what your lot and your budget call for. A modest prefab sunroom in Woodland Hills typically runs $45,000 to $80,000 before permit fees. A custom stick-built sunroom with upgraded glazing and a mini-split system starts around $90,000 and can pass $140,000. The written price goes in your hand before any work starts, and that number does not move at the door.
Glazing and Orientation Choices
Woodland Hills sits in a hot-summer Mediterranean climate, so the direction your sunroom faces matters as much as the glass you pick. We specify low-e glazing on west and south exposures to cut heat gain, and we place operable windows to catch the afternoon breeze that comes down from the Santa Monica Mountains. The goal is a room you can sit in during August without cranking the AC.
Foundation and Tie-In Details
Most sunrooms in Woodland Hills go on a slab-on-grade foundation tied to the existing house with a proper flashing detail at the wall intersection. That detail is where cheap sunrooms fail: water gets in at the roof-to-house seam and rots the eave. Our crews flash and seal that transition to the standard we would accept on a full addition.
Room Additions
Room Additions are the core of what we do in Woodland Hills: a new bedroom, a home office, a family room bump-out, or a primary-suite addition that ties into the existing roofline and foundation. You need this when the house no longer fits the way you live, and moving is not the answer. Fielding ADU Woodland Hills has built room additions throughout Woodland Hills, Sherman Oaks, and Encino, and we also serve clients looking for our Room Addition Contractor in Canoga Park, and every project starts the same way: a written price before any work begins, permits pulled, inspections passed. A single-room bump-out in Woodland Hills typically runs $120,000 to $180,000 before permit fees. A primary suite addition with a bathroom runs $200,000 to $320,000. The variables are foundation type, roofline complexity, and whether the addition touches a load-bearing wall.
Load-Bearing Wall Removal
Most room additions in Woodland Hills involve opening up an exterior wall that is carrying roof load. That means a properly sized beam, often a glulam or an LVL, with the engineering stamped and the permit signed off before we cut anything. We do not guess at beam sizing, and we do not let a homeowner find out later that the header was undersized.
Matching Rooflines and Stucco
Woodland Hills has a lot of mid-century ranch and 1970s Mediterranean homes, and a room addition that does not match the existing roofline looks like exactly what it is: a mistake. We match roof pitch, eave depth, and stucco texture so the addition reads as part of the original house, not a box bolted onto the back.
Modular Home Addition

Modular Home Addition work means building the new space off-site in a factory and setting it onto your foundation in Woodland Hills, which often cuts on-site construction time by a third or more. You need this when you want a shorter build window, less disruption in your yard, and tighter quality control on the framing and weatherproofing. Fielding ADU Woodland Hills works with leading modular platforms including Cover and Plant Prefab, and we also build conventional additions using James Hardie siding where modular does not fit the lot or the design. A factory-built modular addition in Woodland Hills typically runs $180,000 to $280,000 before site work, foundation, and permit fees. Site work and foundation typically add $40,000 to $80,000 depending on access and slope.
Site Preparation and Set
Modular units arrive on a truck, and the crane needs room to swing. On flat Woodland Hills lots with good access, set day is one or two days. On hillside lots off Mulholland or in the canyons, access gets tight and crane costs rise. We walk the site before you sign anything so the written price accounts for the real conditions, not a best-case assumption.
Finishing After Set
Once the module is set, the work is far from done: tying in electrical and plumbing, finishing drywall seams, installing trim, and flashing the marriage line. Most homeowners are surprised by how much finish work remains after set day. We scope it all in the written price so there is no second invoice that shows up halfway through.
Home Addition Plans
Home Addition Plans are the architectural drawings and engineering documents that get your Woodland Hills addition through the city permit process and into the hands of the framing crew. You need these before any real work starts, and you need them right because mistakes on paper become mistakes in concrete and lumber. Fielding ADU Woodland Hills produces and manages home addition plans for our own projects, including those needing a Topanga Room Addition Contractor, working with licensed draftspeople and structural engineers who know what the Los Angeles Department of Building and Safety will accept. Plan and permit costs for a room addition in Woodland Hills typically run $8,000 to $18,000 depending on project scope and whether the addition touches a load-bearing wall or changes the roofline. That cost is in the written price before work starts, not billed as a surprise line item later.
Permit and Setback Requirements
Woodland Hills is part of the City of Los Angeles, which means your addition has to meet LA zoning rules on setbacks, height, and lot coverage. Some lots in the hills have additional restrictions because of the hillside grading ordinance. We check the zoning before we draw anything, so you do not pay for plans that the city will reject.
Engineering and Structural Review
Any room addition in Southern California needs seismic detailing: hold-downs, shear walls, and foundation anchors sized for earthquake loads. We bring a licensed structural engineer onto every addition that changes a load path, and the engineer’s stamp goes on the plans before the permit application goes in.
In Law Suite Builders

In Law Suite Builders specialize in attached or detached living quarters with their own entrance, a bedroom, a bathroom, and usually a small kitchenette, built for aging parents or adult children. In Woodland Hills, an in-law suite is often the most cost-effective way to keep family close without sacrificing privacy on either side. Fielding ADU Woodland Hills builds in-law suites as permitted additions, not as unpermitted garage conversions that will haunt you at resale. A detached in-law suite in Woodland Hills typically runs $180,000 to $280,000 before permit fees, depending on whether you go prefab (through Abodu or Cover) or conventional stick framing. An attached suite that converts existing space runs less, usually $120,000 to $180,000. The written price covers the full scope, including plumbing and electrical tie-ins, so the number you approve is the number you pay.
Separate Entrance and Privacy Details
A real in-law suite needs its own front door, not just a door from inside the house. That means site grading for a path or a small landing, a door that meets accessibility width, and often a low wall or fence line that separates the suite from the main yard. We plan these details from day one, not as an afterthought.
Kitchenette Scope and Plumbing
The difference between a bedroom and an in-law suite is the kitchenette, and the kitchenette is where plumbing costs climb. A sink, a small refrigerator line, and a two-burner cooktop mean running new supply and drain lines, often across the full length of the house. We price that work honestly, and we do not show up later with a change order because the drain line route was longer than the salesman assumed.
ADU Conversion
ADU Conversion means turning existing square footage, most often a garage, into a legal accessory dwelling unit with its own kitchen, bathroom, and entrance. Woodland Hills homeowners pursue ADU conversions because state law since 2020 has forced LA to approve most garage conversions, and because the rental income or family housing solves a real problem. Fielding ADU Woodland Hills converts garages and other existing structures into legal ADUs with permits pulled and inspections passed. A garage conversion to an ADU in Woodland Hills typically runs $90,000 to $150,000 before permit fees, depending on the condition of the slab, the electrical service, and whether the existing structure needs seismic retrofit. A conversion that adds square footage, like extending a detached garage, runs closer to $160,000 to $220,000.
Seismic and Slab Evaluation
Many Woodland Hills garages were built before modern seismic codes, and a conversion means the structure has to meet current standards. We evaluate the existing footings and walls first. If the slab is cracked or the walls lack shear strength, the written price covers the retrofit work, because we found it before we quoted, not after we opened the wall.
Utility Upgrades and Service Panels
A garage has one 20-amp circuit and no plumbing. An ADU needs a subpanel, dedicated circuits for the kitchen and HVAC, and new water and drain lines. In older Woodland Hills homes, the main service panel often needs an upgrade too. We scope the electrical work from the start, so the permit set matches the build and there are no open walls at inspection time.
Brands We Service
Fielding ADU Woodland Hills works with the major prefab and modular platforms, and we have built and finished units from Abodu and Cover in the Woodland Hills area. With Abodu units, we handle the site work, foundation, utility connections, and all finish work after the unit is set, and we coordinate the permit package with the factory drawings. With Cover, we manage the panelized wall and floor assembly on your lot, which gives more design flexibility on irregular Woodland Hills sites than a fully factory-built module does.
We also build conventional additions using James Hardie siding and Tuff Shed-style structures where a lighter, faster build is the right answer for the budget and the lot. Whether you have a specific brand in mind or want us to recommend the right build method for your situation, we can help. Call (559) 254-0116 and ask for Reed Calloway.
Signs You Need a Pro Right Now
- You found a crack running through the slab or the stem wall. Some cracks are cosmetic, but a horizontal crack in a stem wall or a crack that has opened more than a quarter inch often means soil movement. In Woodland Hills, expansive clay soil is common, and a room addition built on a moving slab will crack again. We evaluate the foundation before we quote anything.
- Your current contractor stopped returning calls, and the permit board is blank. That means the job is not permitted and the work already done may need to be exposed, inspected, and redone. We take over stalled projects, pull the permits, and bring the work up to code before we build further.
- The existing roof line or wall is sagging where the addition will tie in. A sagging roofline means the existing structure is underbuilt or has water damage. Tying a new addition into a failing structure just spreads the problem. We shore it up, document the repair, and only then frame the addition.
- You got a quote that seems too low to be real. A room addition in Woodland Hills that is quoted at $60,000 all-in is either not permitted, not engineered, or not going to finish. Written price does not mean lowest price. It means the price is honest and it holds.
- The city sent a notice about unpermitted work on your property. This can happen when you buy a house and the previous owner added a room without permits. We handle code compliance and legalization in Woodland Hills, and we have done it enough times to know what the LA inspectors will accept.
Our Process, Step by Step
- 1
Walk the site and listen. Reed Calloway or a senior project lead visits your Woodland Hills property, walks the space, and asks what the room needs to do for you. We look at access, slope, soil, and the existing structure. This visit is free and it comes with no pressure.
- 2
Written price, before any work starts. After the walk, you get a written price that covers the scope we discussed: permits, plans, engineering, materials, labor, and cleanup. The number you approve on day one is the number on the final invoice. No change orders unless you change the scope.
- 3
Plans, engineering, and permit. We produce or coordinate the home addition plans, run the structural engineering, and submit the permit package to the City of Los Angeles. We handle the plan checks and the corrections. You do not stand in line at the building department.
- 4
Build by The Garrison Code. Background-checked, uniformed crews show up in the window, keep the site clean, and build to the permit set. We communicate during the build. You know who is on your site, and you know what is happening each week.
- 5
Final inspection and the 365-Day Done Right Promise. The city signs off, we walk the finished addition with you, and you get the written guarantee: workmanship defects are covered for one full year. If something fails inside that year, we come back at no charge and make it right.
How Much Does Room Addition Contractor Cost in Woodland Hills?
A typical room addition in Woodland Hills runs $120,000 to $320,000 depending on scope. A simple single-room bump-out of 200 to 300 square feet, no plumbing, starts around $120,000. A primary suite addition with a bathroom runs $200,000 to $320,000. A sunroom runs $45,000 to $140,000 depending on glazing and whether it is conditioned. A garage conversion to an ADU runs $90,000 to $150,000. A modular or prefab addition runs $180,000 to $280,000 before site work. These ranges include labor, materials, plans, engineering, and permit fees. What moves the price: foundation condition, roofline tie-in complexity, site access for equipment, whether the addition touches a load-bearing wall, and the finish level of the interior.
The best way to avoid overpaying in Woodland Hills is to get a written line-item price before work starts and to hold the contractor to it. A vague proposal that says “addition: $150,000” is an invitation for a change order later. Our free estimate includes a walk of the site, a scope document, and a written price. Call (559) 254-0116 to schedule one.
Our Service Area Near Woodland Hills
Fielding ADU Woodland Hills builds room additions throughout the west San Fernando Valley and the neighboring hillside communities. We work in Sherman Oaks, Encino, Tarzana, Winnetka, Reseda, Canoga Park, West Hills, Calabasas, Chatsworth, Topanga, and Pacific Palisades. If you are in Woodland Hills or any of these nearby communities, we already know the local zoning quirks and the hillside conditions. Our home base is here in the Valley, which means shorter drive times for site visits and faster response when you call (559) 254-0116. We are your Room Addition Contractor in Woodland Hills, and we show up when we say we will.
Serving Woodland Hills, CA - Our Local Coverage Area
We’re based in the Woodland Hills area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
Frequently Asked Questions About Room Addition Contractor in Woodland Hills
A room addition contractor is a licensed builder who designs, permits, and constructs new living space attached to or adjacent to an existing home, and you can learn more in our Room Addition Contractor Maintenance Checklist for Woodland Hills Homeowners. In Woodland Hills, that means handling the architectural plans, structural engineering, permit submittal to the City of Los Angeles, foundation work, framing, roofing, electrical, plumbing, drywall, and finish work. At Fielding ADU Woodland Hills, we act as the single point of responsibility for the entire project, so you do not have to hire and coordinate separate trades. Call (559) 254-0116 for a free estimate and a written price.
A typical single-room addition in Woodland Hills takes four to seven months from the first site visit to final inspection. The permit phase alone usually runs six to ten weeks with the City of Los Angeles. Prefab and modular additions can cut the on-site construction time significantly, but the site work and finish work still take weeks. We lay out a real schedule in your written proposal, and we hold to it.
A room addition in Woodland Hills typically costs between $120,000 and $320,000 depending on size, scope, and finish level. A single-room bump-out starts around $120,000, a primary suite with bathroom runs $200,000 to $320,000, and a garage conversion to an ADU runs $90,000 to $150,000. Every project gets a written price before work starts. Call (559) 254-0116 for an exact quote, because the range depends on your foundation, your lot, and your roofline.
Yes. Fielding ADU Woodland Hills works with Abodu and Cover prefab platforms, and we build conventional additions using James Hardie siding and Tuff Shed-style structures. We match the build method to your budget and your lot. If you have already researched a specific brand, we can tell you whether it fits your Woodland Hills property before you spend money on a deposit.
Room additions are planned construction, not emergency work, so we do not sell same-day starts or 24-hour dispatch for a new addition. What we do offer is a live person answering the phone 24 hours a day, 7 days a week. If you have a question about a stalled project, a failed inspection, or a code issue, you can call (559) 254-0116 at any hour and speak to a person who can help you plan the next step.
Every room addition we build in Woodland Hills carries the 365-Day Done Right Promise in writing. If any workmanship defect appears within one full year, we return at no charge and correct it. The guarantee is spelled out in your contract: what it covers, how long it runs, and exactly how we make it right. No fine print that disappears when you need it.
Start by deciding what the space needs to do: sleep, work, house family, or rent. Then walk your property and note access points, slopes, and any existing cracks or damage you have noticed. Gather any old plans or permits if you have them. Then call Fielding ADU Woodland Hills at (559) 254-0116. We handle the rest, from zoning checks to written pricing, and the first site visit is free.
Schedule Your Room Addition Contractor Service in Woodland Hills Today
If you are done with vague estimates and missed schedules, call (559) 254-0116. You will reach a live person, day or night. We will schedule a free site visit, put the price in writing before any work starts, and stand behind the build for a full year under the 365-Day Done Right Promise. That is the Garrison Standard, and it is how we built room additions in Woodland Hills since opening our doors. Ask for Reed Calloway.
Written by Reed Calloway, Owner at Fielding ADU Woodland Hills, serving Woodland Hills and the west San Fernando Valley since 2006.









