Custom home cost estimator
Honest pricing,
at a glance.
A live calculator built from real Casteca Homes 2026 pricing across Washington, Iron, and Kane counties. Adjust square footage, location, finish level, and project complexity to see an honest cost range for your Southern Utah custom build, then request a fully line-itemed estimate by email.
Build inputs
Tune your estimate.
Finish level
Project complexity
Your estimate, St. George, UT
4,000 sq ft, Premium finish, moderate
Low
$2.3M
$2,281,600
Most likely
$2.5M
$2,480,000
High
$2.8M
$2,777,600
Effective cost $620 per sq ft. The range above reflects normal variance for sitework, allowances, and design choices. Permit fees, impact fees, landscaping, pools, and lot purchase are not included.
Breakdown
| Base rate | $600/sq ft, Premium |
| Square footage | 4,000 sq ft |
| Base cost | $2,400,000 |
| Location, St. George | 1.00x, Washington and Kane counties |
| Complexity, Moderate | + $80,000 |
| Most likely total | $2,480,000 |
How we calculated this
The numbers behind this calculator come from current Southern Utah market data and our own line-item pricing model for St. George, Ivins, Hurricane, Washington, Cedar City, and Kanab. We start with a finish-level cost-per-square-foot baseline (Premium = $600 per sq ft, St. George), apply a county-level adjustment, and add a complexity premium for steep lots, retaining walls, and unusual architecture.
What's included
The estimate covers turnkey construction, foundation through final keys, including framing, mechanical, electrical, plumbing, insulation, drywall, Designer-grade everything, full-slab natural stone, custom steel doors, smart-home wiring, integrated audio., interior trim, roofing, exterior cladding, basic site grading, and a covered patio. Project management, weekly walkthroughs, and our 2-year workmanship warranty are baked into the price.
What's not included
Lot purchase, impact fees, building permits, geotechnical reports, civil engineering for difficult sites, landscaping past the basic envelope, pool and spa, custom outdoor kitchens, casita additions, and furniture are quoted separately. We will line-item every one of these in your formal proposal so there are no surprises.
Why our cost-per-foot is honest
No teaser pricing.
No surprise change orders.
Across Southern Utah, the most common reason custom home budgets blow up is "$300 per square foot" advertising that ignores allowances, sitework, and finish reality. We do not play that game. The number you see here is in the same currency as your final contract.
For a 4,000 to 6,000 sq ft Casteca home in St. George, Ivins, or Washington in 2026, you should plan on $450 to $750 per sq ft all-in, depending on finish level and architectural complexity. Cedar City, Enoch, and Iron County typically run 10 to 15 percent lower because of labor, material logistics, and impact fees. Springdale and Kanab can run higher due to design review and limited supply.
Once we sign a pre-construction agreement, we provide a fully line-itemed budget you can take to your lender. Through construction, you watch every line item in your project portal, live, against the contract.
Ready to get specific?
Let's price your
actual build.
Calculators are a starting point. A 30-minute call is where we turn your number into a real budget for your real lot.