Garage Construction & ADUs Cost Guide — St. Louis, MO

Verified 2025 pricing for garage construction & adus services in St. Louis. Updated quarterly from local contractor data.

Service Cost Ranges

Service	Low	Average	High	Unit
Detached Garage Construction	$20,000	$45,000	$100,000	per project
ADU / Garage Apartment	$60,000	$120,000	$250,000	per project
Carport Installation	$4,000	$9,000	$25,000	installed

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Older housing stock (pre-1958) increases complexity and materials cost

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✓Bundle multiple services

✓Check for manufacturer rebates

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