Room Addition Cost Estimator | Level Up Contractor
Free Estimation Tool
Room Addition Cost Estimator
Room additions in Los Angeles typically range from $80,000 to $300,000+ depending on size, scope, and what’s being added. Answer each section for a detailed estimate.
This helps us understand the intended use, ceiling height requirements, and any special structural needs.
🛏️
Bedroom
Standard bedroom addition. Includes closet framing, window, door, and all finishes.
💼
Home Office / Den
Dedicated workspace or den. May include additional outlets and data wiring.
🛋️
Living Room / Family Room
Open living space addition. Often involves larger spans and higher ceilings.
☀️
Sunroom / Enclosed Patio
Light-filled addition with large windows or sliding glass doors. May have different roofing requirements.
🏠
In-Law Suite
Private suite addition — bedroom only, no kitchen. Includes separate entrance if needed.
Step 2 · Scope of Addition
What’s included in this addition?
Select what you’re adding. If you include a bathroom or kitchen, we’ll walk you through those details after the room addition questions.
🏗️
Room Addition Only
Adding square footage — bedroom, office, living room, or sunroom. No bathroom or kitchen included.
💚 Straightforward scope
🏗️🚿
Room Addition + Bathroom Addition
Adding a room with an en-suite or adjacent bathroom. After the room questions, we’ll walk through the full bathroom estimate.
🟡 Adds full bathroom scope to the estimate
🏗️🍳
Room Addition + Kitchen Remodeling
Adding a room with a new kitchen — common for ADU / JADU or in-law suite expansions. After the room questions, we’ll walk through the full kitchen estimate.
Full ADU / JADU or in-law suite — room, bathroom addition, and kitchen remodeling all included. We’ll walk through each section separately.
🔴 Full scope — all three sections estimated
Step 3 · Size
What’s the approximate size of the addition?
Room addition pricing is not linear — even smaller additions require the same trades and permit process. A larger addition spreads that fixed cost over more square footage.
📐 How pricing works: Smaller additions (under 200 sq ft) cost more per square foot because the fixed costs of permits, engineering, foundation, and trade mobilization are spread over less area. Larger additions become more cost-efficient per sq ft.
300sq ft
100 sq ft — small2,000 sq ft — large
Or pick a size range
Small
100–250 sq ft — single room, tight footprint
🔴 Higher per sq ft — fixed costs spread thin
Medium
250–750 sq ft — comfortable room or suite
🟡 Mid-range per sq ft
Large
750–2,000 sq ft — large suite or full addition
💚 More linear pricing — better efficiency per sq ft
Step 4 · Foundation
What type of foundation does the addition need?
Foundation cost is included in the overall per square foot price. The type affects the rate — slab is most cost-effective, raised and crawl space add to the overall scope.
🏗️
Slab on Grade
Concrete slab poured directly on the ground. Common in Los Angeles. Most cost-effective foundation option.
💚 Most common — standard cost
🪵
Raised Foundation
Stem wall with crawl space below. Matches existing raised foundation on older LA homes. More complex and costly than slab.
🟡 Moderate additional cost
🔩
Crawl Space / Pier & Beam
Elevated foundation with accessible crawl space. Common for sloped lots or matching existing pier & beam structures.
🔴 Higher cost — more materials and labor
❓
Not Sure Yet
Foundation type will be determined during site visit and structural engineer review.
🟡 We’ll assess and include in detailed quote
Step 5 · Roof
What type of roof will the addition have?
The roof ties the addition to the existing structure. Both the style and material affect labor and overall cost.
Roof style
🏠
Match Existing Roofline
Ties into the existing roof structure and matches the current pitch and style. Most common choice.
💚 Standard — clean integration with existing structure
🔺
New Gable Roof
Triangle-shaped pitched roof with two sloping sides. Classic and versatile design.
🟡 Moderate — new framing required
🔷
Hip Roof
All four sides slope downward. More complex framing but very stable and attractive.
🟡 Moderate to higher — more complex framing
📐
Shed / Flat Roof
Single sloping plane. Modern look, often used for sunrooms or contemporary additions.
💚 Simpler framing — good for modern style
Roof material
🏘️
Asphalt Shingles
Most common roofing material in LA. Cost-effective, widely available, easy to match existing.
💚 Most affordable — standard choice
🏛️
Concrete / Clay Tile
Very common in Los Angeles. Durable and classic — matches most Southern California homes.
🟡 Moderate — heavier material, more structural support
⬛
Flat / TPO / Built-Up Roof
Torch-down, TPO, or built-up membrane system for flat or low-slope roofs.
🟡 Moderate — specialized waterproofing required
🔩
Metal Roof
Standing seam or corrugated metal. Modern look, very durable, long lifespan.
🔴 Higher — premium material and specialized install
Ceiling height inside the addition
8 ft — Standard
Standard residential ceiling height. Most cost-effective framing.
💚 Standard framing cost
9 ft
One foot taller — feels more spacious, adds modest cost.
🟡 Minor framing addition
10 ft
Open and airy feel — common in family rooms and living spaces.
Grand ceiling height — dramatic effect, significant structural and framing cost.
🔴 Significant framing addition
Step 6 · HVAC
How will the addition be heated and cooled?
Every livable room addition requires climate control. Select the approach that best fits your home and project.
🌬️
Extend Central HVAC
Tie the addition into the existing central heating and cooling system. Requires duct extension and may need system capacity evaluation.
🟡 Moderate — depends on existing system capacity
❄️
Mini-Split System
Dedicated ductless mini-split unit for the addition. Independent control, highly efficient, no duct work needed.
🟡 Moderate — self-contained unit, very efficient
Step 7 · Windows & Doors
How many windows and doors will the addition have?
Each window and door opening requires framing, installation labor, and finishing. Client supplies windows and doors — we install everything.
Windows
2
Exterior Doors
1
Sliding / French Doors
0
Interior Doors
1
Special window types
Select all that apply
🌤️
Skylights
Roof-mounted skylights — requires structural opening and waterproofing.
🔴 Significant addition — roof penetration and waterproofing
🖼️
Large Picture / Floor-to-Ceiling Windows
Oversized fixed windows — requires additional structural header work.
🟡 Moderate — larger header framing required
Step 8 · Electrical & Finishes
Electrical and any special finish features?
All additions include standard outlets, switches, and lighting rough-in. Select any additional electrical or special features needed.
✅ Standard electrical always included — outlets, switches, and lighting per code. Permit, inspections, and structural engineer plans are also always included.
Additional electrical
Select all that apply
🌐
Data / Ethernet Wiring
Structured wiring for internet, TV, and smart home — ideal for offices and living rooms.
💚 Minor addition
🔊
In-Wall Speaker Wiring
Pre-wire for surround sound or built-in speakers.
💚 Minor addition
🌡️
In-Floor Radiant Heat
Electric heating mat under tile or hardwood. Mat is client-supplied.
🟡 Moderate — wiring and thermostat
⚡
EV Charger Outlet
240V dedicated outlet for electric vehicle charging — common for additions near garage.
🟡 Moderate — dedicated 240V circuit
Lighting — quantity
LED Recessed Lights
0
Ceiling Fan Rough-Ins
0
Flooring type
Hardwood
Solid or engineered hardwood to match existing home.
🟡 Mid-range labor
Luxury Vinyl Plank
Durable floating floor — waterproof and cost-effective.
💚 Standard labor rate
Tile
Porcelain or ceramic tile — common for sunrooms and in-law suites.
🟡 Moderate — depends on pattern
Timeline
🔥 ASAP
Ready to start within 1–2 months.
📅 1–3 Months
Planning ahead, ready soon.
🗓️ 3–6 Months
Still in research phase.
⏰ Flexible
No rush — exploring options.
🚿
Phase 2 — Bathroom Addition
Now let’s estimate the bathroom inside the addition
You selected a room addition with a bathroom. Answer the following questions to build the bathroom portion of your estimate. We’ll combine both at the end.
The bathroom estimate covers labor and rough materials only — finish materials (tile, vanity, fixtures) are priced separately with your designer.
Bathroom · Step 1
What type of bathroom is being added?
This sets the scope and fixture count for the bathroom inside the addition.
🛁
Master En-Suite
Full bathroom connected to the master bedroom. Larger scope, more fixtures.
🚿
Guest / Hall Bathroom
Full bathroom accessible from hallway or multiple rooms.
🚽
Half Bath / Powder Room
Toilet and sink only — no shower or tub.
Bathroom · Step 2
Shower pan or tub — what’s going in?
🚿
Custom Tile Shower Pan
Built mortar bed with full waterproofing. Required for any custom tile shower floor. Cost scales with shower size.
🟡 The bigger the shower, the higher the cost
🛁
Tub Installation (labor only)
Alcove, drop-in, or freestanding tub. Client supplies tub.
💚 Installation labor included in finish phase
🛁🚿
Both — Tub + Separate Shower
Separate soaking tub and walk-in shower.
🔴 Both scopes apply
✓
Not Applicable
Half bath — no shower or tub needed.
Approximate shower size
36sq ft
12 sq ft80 sq ft
Bathroom · Step 3
Bathroom plumbing details.
All new plumbing for the addition. Use the counters to specify fixture counts — supply lines, drain connections, and rough-in are all included.
Sinks
1
Toilets
1
Shower Connections
1
Tub Connections
0
🤖
Smart Toilet
Requires dedicated outlet — flagged for electrical.
🚽
Standard Toilet
No outlet needed for the toilet.
Bathroom · Step 4
Bathroom framing complexity.
Select framing complexity and number of shampoo niches for the bathroom.
Low
Simple
Standard layout
No structural changes
💚 Lower framing cost
Mid
Moderate
Shower pan build
Ceiling or soffit detail
🟡 Mid-range framing
High
Complex
Multiple features
Built-in storage
🔴 Higher framing cost
Shampoo niches
Number of Shampoo Niches
0
Shower bench
✓ No Bench
💚 No added framing
🪑
Regular Bench
🟡 Moderate addition
📐
Cantilever Bench
🔴 Structural support required
Bathroom · Step 5
Tile installation for the bathroom.
Labor only — you supply the tile. Wall and floor are calculated separately.
Wall tile layout
Standard Layout
Straight horizontal/vertical set.
💚 Standard labor rate
Complex Layout
Herringbone, diagonal, large format, mosaic.
🔴 Higher labor rate — more cuts and time
Floor tile layout
Standard Layout
Straight set porcelain or ceramic.
💚 Standard labor rate
Complex Layout
Diagonal, penny tile, mosaic, herringbone.
🔴 Higher labor rate — intricate patterns take more time
Wall Tile (sq ft)
80
Floor Tile (sq ft)
45
Bathroom · Step 6
Bathroom electrical.
GFCI outlets and exhaust fan are code-required and always included. Select any additional electrical.
✅ GFCI outlets + exhaust fan always included — required by California building code.
💨
Standard Exhaust Fan
💚 Included standard
💨💡
Fan + Light Combo
💚 Minor upgrade
Additional lighting
LED Recessed Lights
0
Sconces / Pendants
0
Specialty
Select all that apply
🌡️
In-Floor Radiant Heat
🟡 Moderate addition
🌡️🧣
Electric Towel Warmer
💚 Minor addition
Bathroom · Step 7
Bathroom drywall and paint.
All new construction — select the drywall scope that matches your bathroom plan.
Standard New Build
Full drywall and paint for new construction bathroom — standard scope.
💚 Standard for new addition
Premium Finish
Smooth plaster finish, specialty paint, or additional detail work.
🟡 Higher finish quality
Select all that apply
🔇
Soundproofing Insulation
🟡 Moderate addition
💧
Extra Moisture Barrier
💚 Minor addition
🍳
Phase 2 — Kitchen Addition
Now let’s estimate the kitchen inside the addition
You selected a room addition with a kitchen. Answer the following questions to build the kitchen portion of your estimate. We’ll combine both at the end.
Cabinets and countertops are included in the kitchen estimate. All other finish materials (tile, backsplash, appliances, fixtures) are separate.
Kitchen · Step 1
What’s the approximate size of the kitchen?
150sq ft
60 sq ft — small galley400 sq ft — large open kitchen
Kitchen · Step 2
Kitchen plumbing & range connection.
Kitchen Sinks
1
Bar / Prep Sinks
0
Range connection type
🔥
Gas Line for Range
Run a new gas supply line to the range location. Required for gas cooktops and ranges.
🟡 Moderate — gas line rough-in and connection
⚡
220V Line for Electric Range
Dedicated 240V / 50-amp circuit for electric range or induction cooktop.
🟡 Moderate — dedicated high-voltage circuit
Select all that apply
🍽️
Dishwasher Connection
Supply and drain connection for dishwasher.
🧊
Refrigerator Water Line
Supply line for ice maker or water dispenser.
🫗
Pot Filler
Wall-mounted pot filler above range.
Kitchen · Step 3
Kitchen electrical and hood ventilation.
✅ 7–8 dedicated circuits, GFCI outlets, and permit always included — required by code for all kitchen additions.
Hood type
💨
Standard Range Hood
🟡 Moderate — ductwork and wiring
🌪️
Island Hood / Ceiling Vent
🔴 Higher — ceiling duct run required
Lighting counters
LED Recessed Lights
0
Under-Cabinet LED Runs
0
Kitchen · Step 4
Cabinet installation.
We supply and install cabinets. Enter base and upper cabinet runs separately — pricing is based on linear footage and cabinet type.
Cabinet type
Stock / Prefab
💚 Lower end
Semi-Custom
🟡 Mid-range
Full Custom
🔴 Higher end
Base Cabinets (LF)
15
Upper Cabinets (LF)
8
Kitchen · Step 5
Countertop installation.
We supply and install countertops including a 5% overage allowance. Select the material and enter the total countertop area.
💎
Quartz
🟡 Mid to higher range
🪨
Granite
🟡 Mid to higher range
⬜
Marble / Natural Stone
🔴 Premium — highest complexity
🟫
Laminate / Butcher Block
💚 Lower end
Total Countertop Area (sq ft)
30
Final · Your Estimate
Your Complete Addition Estimate
Built from all your selections — room addition plus any bathroom or kitchen included.
What You Get When You Work With Us
More Than a Quote — A Complete Vision for Your Home
Submit your estimate and unlock everything included with every Level Up Contractor project:
🎨
Free 3D Design
Full 3D rendering of your addition before a single wall goes up.
🤝
Free Consultation
On-site visit with Ray — no salespeople, just honest expert advice.
💡
Expert Ideas & Insights
10+ years of addition expertise — we know what adds value and what to avoid.
Note: This is a ballpark estimate based on your selections and current LA rates. Final pricing is determined after a free on-site visit and structural engineer review. We provide a detailed written estimate before any work begins — no surprises.
Get Your Precise Quote
Fill in your details below. Your estimate and all project details will be sent to our team — we’ll reach out within 24 hours to schedule your free consultation.
