How much does adu construction cost in Katy, TX?

Most Katy homeowners spend between $154,500 – $309,000 on adu construction, with an average around $231,800. Local labor prices 3% above the national average, so Katy quotes tend to land at the higher end of national ranges.

Why is adu construction more or less expensive in Katy than elsewhere?

West Houston suburb with higher-end finish expectations. Flood-zone rules can affect foundations, decks and fencing.

Do I need a permit for adu construction in Katy, Texas?

County or city permits plus HOA approval typically apply. Always confirm current requirements with the local building department before signing a contract, and make sure the permit is pulled by your licensed contractor.

How many quotes should I get in Katy?

Get at least three written quotes from licensed, insured Texas contractors. Comparing line items — not just the bottom line — is the fastest way to spot an inflated bid in the Houston market.

How much does adu construction cost in 2026?

Most homeowners pay between $150,000 and $300,000, with a national average near $225,000. Small, simple jobs land at the low end; large or premium-material jobs run well above the high end.

What is the cost per square foot?

Installed pricing usually runs $250.00 to $500.00 per square foot, including labor and materials. Expensive metros can run 15–45% higher than that range.

What drives the price up the most?

Scope and access. Larger quantities lower your per-square foot price, but difficult access, demolition of existing work, structural repairs found mid-job, premium materials and rush scheduling each add 8–30%.

Permits are typically required when the work changes structure or ties into electrical, plumbing, gas or mechanical systems. Budget $75–$600 in most cities and confirm whether your contractor pulls it — unpermitted work can block a future home sale.

How long does the job take?

Most residential projects of this type finish in one to five working days once materials are on site. Custom orders, inspections and weather are the usual causes of delay.

How many quotes should I get?

Three. Bids on the same scope commonly vary 20–40%, and the middle bid with the strongest warranty and references is usually the best value — the cheapest bid often excludes prep, disposal or permits.

Home/Cost guides/ADU Construction/Katy, TX

Houston · Texas

ADU Construction cost in Katy, TX

Katy homeowners typically pay $154,500 – $309,000 for adu construction. Local labor and materials price 3% above the national average.

Get my Katy estimate Use the Katy calculator

Katy average

$231,800

Typical low

$154,500

Typical high

$309,000

Per square foot

$260 – $515

Sample ZIP

77494

What drives Katy pricing

Local labor

West Houston suburb with higher-end finish expectations.

Permits & code

County or city permits plus HOA approval typically apply.

Climate & conditions

Flood-zone rules can affect foundations, decks and fencing.

Instant cost calculator

Adjust the inputs to see live pricing

ADU size (sq ft)600 square feet

Quality / material level

Site access

Removal / prep work

Timing

Estimated project cost

$136,800 – $188,100

Most homeowners pay around $162,450

Compare quality / material level

Cost by material in Katy

Installed Katy pricing per square foot.

Option	Installed cost	Pros	Cons
Prefab studio ADU	$240 – $330	—	—
Site-built 1-bedroom	$330 – $435	—	—
Site-built 2-bedroom	$435 – $560	—	—
Custom high-end ADU	$560 – $775	—	—

Where the money goes in Katy

A typical $231,800 Katy project, broken down by line item.

Labor0.45% · $1,043
Materials0.38% · $881
Permits & inspections0.05% · $116
Overhead & profit0.12% · $278

Common add-ons

Extras that show up on Katy quotes but rarely in the headline price.

Utility connections

$8,250 – $30,900

Site work and foundation

$15,500 – $61,800

Design and permits

$8,250 – $30,900

Impact fees

$2,050 – $20,600

Ways to save in Katy

Use pre-approved ADU plans where your city offers them — saves months and design fees.
Detach only if required; attached and conversion ADUs cost far less.
Collect three written bids on an identical scope — spreads of 20–40% are normal.
Book in the off-season and stay flexible on the start date to save 5–15%.
Bundle nearby work into one mobilization so you only pay setup and travel once.
Ask what the contractor would change to cut 10% without hurting durability.

Katy FAQs

Get a Katy price you can budget against

Answer a few questions about your project and we'll model a low, average and premium price for your TX ZIP code — then connect you with vetted local pros.

Get free quotes from certified pros

More Katy research

Best adu construction companies in Katy ADU Construction permits in Texas ADU Construction near me All Texas prices

ADU Construction cost near Katy

ADU Construction cost in Houston, TX

$150,000 – $300,000

ADU Construction cost in Sugar Land, TX

$157,500 – $315,000

ADU Construction cost in The Woodlands, TX

$160,500 – $321,000

ADU Construction cost in Pearland, TX

$151,500 – $303,000

ADU Construction cost in Pasadena, TX

$145,500 – $291,000

ADU Construction cost in Spring, TX

$150,000 – $300,000

More Texas cities

Dallas Fort Worth Plano Frisco Arlington Irving McKinney Denton

Other project costs in Katy

Fence Installation in Katy

$1,545 – $4,120

Roof Replacement in Katy

$8,755 – $35,020

Kitchen Remodel in Katy

$18,540 – $97,850

HVAC Replacement in Katy

$5,665 – $18,540

Deck Building in Katy

$4,532 – $12,360

Window Replacement in Katy

$464 – $1,545

See every Katy cost guide