Twin Falls County

Home permits and project costs in Twin Falls, ID

Twin Falls sits in Twin Falls County, Idaho. Snow load, hail and deep freeze-thaw cycling drive roofing, insulation and exterior envelope specifications well above Sun Belt minimums. Work outside city limits is permitted by the county building department rather than the city.

Model reviewed August 2026

Local cost index

-7%

vs national average

Permit fee index

-17%

vs national baseline

Population

55,285

Homeownership

Do you need a permit in Twin Falls?

For most structural work, yes

Twin Falls enforces idaho residential code, based on the irc through Twin Falls County. Roofing, electrical, plumbing, structural, pools and most exterior additions require a permit and inspection. Cosmetic work — paint, flooring, cabinet swaps — generally does not.

Project costs in Twin Falls

National baselines adjusted by the local labor and materials index.

Project	Typical cost	Permit	Deep pages
Roof Replacement	$8,900 – $29,900	required	Cost·Permit
AC Replacement	$4,900 – $14,600	required	Cost·Permit
Fence Installation	$2,200 – $10,300	usually required	Cost·Permit
Water Heater Replacement	$1,100 – $5,000	required	Cost·Permit
Pool Installation	$35,400 – $107,200	required	Cost·Permit
Window Replacement	$7,100 – $32,100	required	Cost·Permit
Electrical Panel Replacement	$1,800 – $6,300	required	Cost·Permit
Generator Installation	$6,100 – $20,500	required	Cost·Permit
Solar Panel Installation	$14,300 – $45,700	required	Cost·Permit
Kitchen Remodel	$17,000 – $86,900	conditional	Cost·Permit
Bathroom Remodel	$8,500 – $39,500	conditional	Cost·Permit
Driveway Replacement	$3,900 – $17,800	usually required	Cost·Permit
Paver Patio & Walkway	$3,300 – $15,000	conditional	Cost·Permit
Deck Construction	$5,100 – $26,100	required	Cost·Permit
Shed Installation	$1,700 – $11,200	conditional	Cost·Permit
Whole-House Repipe	$4,200 – $14,800	required	Cost·Permit
EV Charger Installation	$700 – $3,900	required	Cost·Permit
Hurricane Shutter Installation	$3,000 – $16,800	required	Cost·Permit
Pool Enclosure / Screen Cage	$8,400 – $39,100	required	Cost·Permit
Septic System Replacement	$7,000 – $26,200	required	Cost·Permit
Impact Window Installation	$8,500 – $39,600	required	Cost·Permit
Exterior Door Replacement	$800 – $6,100	usually required	Cost·Permit
Garage Door Replacement	$1,300 – $7,000	required	Cost·Permit
Siding Installation	$7,500 – $35,500	usually required	Cost·Permit
Stucco Repair	$800 – $15,000	conditional	Cost·Permit
Soffit & Fascia Replacement	$1,700 – $10,300	conditional	Cost·Permit
Gutter Installation	$800 – $6,100	rarely required	Cost·Permit
Roof Repair	$400 – $4,400	conditional	Cost·Permit
Flat Roof Replacement	$5,600 – $26,100	required	Cost·Permit
Attic Insulation	$1,100 – $7,100	rarely required	Cost·Permit
Ductwork Replacement	$2,400 – $11,300	required	Cost·Permit
Mini Split Installation	$2,300 – $11,800	required	Cost·Permit
Flooring Installation	$2,400 – $18,900	rarely required	Cost·Permit
Tile Installation	$1,700 – $14,900	rarely required	Cost·Permit
Interior Painting	$1,400 – $8,800	rarely required	Cost·Permit
Exterior Painting	$2,600 – $13,900	rarely required	Cost·Permit
Drywall Repair	$300 – $4,200	rarely required	Cost·Permit
Kitchen Cabinet Refacing	$4,200 – $18,700	rarely required	Cost·Permit
Countertop Replacement	$2,100 – $11,400	rarely required	Cost·Permit
Tub to Shower Conversion	$3,300 – $14,900	usually required	Cost·Permit
Sod Installation	$900 – $6,600	rarely required	Cost·Permit
Irrigation System Installation	$2,100 – $9,400	conditional	Cost·Permit
Tree Removal	$400 – $5,000	conditional	Cost·Permit
Outdoor Kitchen	$5,600 – $42,100	usually required	Cost·Permit
Seawall Repair	$7,400 – $88,300	required	Cost·Permit
Dock Construction	$8,400 – $79,000	required	Cost·Permit
Well Installation	$5,100 – $23,300	required	Cost·Permit
Mold Remediation	$1,400 – $13,900	conditional	Cost·Permit
Water Softener Installation	$1,100 – $6,100	usually required	Cost·Permit
Home Addition	$42,000 – $261,200	required	Cost·Permit
Heat Pump Replacement	$6,100 – $20,700	required	Cost·Permit
Furnace Replacement	$3,000 – $10,800	required	Cost·Permit
Foundation Repair	$2,600 – $30,000	usually required	Cost·Permit
Basement Waterproofing	$2,800 – $16,900	conditional	Cost·Permit
Drain Field Replacement	$5,600 – $23,300	required	Cost·Permit
Toilet Installation	$200 – $1,000	rarely required	Cost·Permit
Hot Tub Installation	$5,100 – $20,600	usually required	Cost·Permit

Twin Falls permitting basics

Jurisdiction	Twin Falls, Twin Falls County
Building department	Confirm with the city or county
Permit portal	No verified online portal on file
Owner-builder permits	Owner-builder permits allowed on owner-occupied property
Contractor verification	Verify any license with Idaho Division of Building Safety before signing

Sources

Sources & verification

Idaho Division of Building Safety

Model vintage August 2026. The links above are the issuing agencies' own pages — we publish them so you can confirm the current rule yourself, not as evidence that each fact on this page was re-checked with them today. Cost figures are modeled estimates based on national baselines adjusted for local labor and material pricing, not quotes. Permit rules change; confirm with the building department before starting work.