Cost to Build Guide / The full guide, 2026
The 2026 cost to build
in Southern Utah.
This is the same pricing model we use to budget our own custom homes across Washington, Iron, and Kane counties, written down plainly. Every dollar figure here comes from one source of truth, so it stays consistent with our estimator. These are build costs. Land, sitework beyond normal grading, landscaping, and pools are quoted as separate line items.
One honest note up front: Casteca is a new Southern Utah builder, licensed Utah GC 14205355-5501, insured and bonded, with a 2-year warranty. We do not have a decade of completed homes to point to yet, and we price below the established custom builders because of that. The numbers below reflect that position.
Section 01
Build cost per square foot,
by finish level.
We bid custom homes by finish level, not by a single flat rate, because the finishes are where most of the variation lives. These are build costs in the Washington County market before lot and county adjustments. Iron and Kane counties run lower (see Section 06).
Standard finish
$305
per square foot
Refined and durable selections, clean detailing, no fuss. The honest baseline for a custom home.
A 4,500 sq ft home: $1,372,500
Premium finish
$385
per square foot
Designer-grade throughout: better cabinetry, stone counters, upgraded tile and flooring, more built-ins.
A 4,500 sq ft home: $1,732,500
Luxury finish
$525+
per square foot
No-compromise and fully bespoke: custom millwork, imported materials, high-end mechanical systems.
A 4,500 sq ft home: $2,362,500
Section 02
What drives the range.
Two homes the same size can land hundreds of thousands of dollars apart. Here is where that gap actually comes from, in roughly the order it matters.
01
Finish level
The single biggest lever. Cabinetry, countertops, flooring, tile, and fixtures are where a Standard home and a Luxury home of identical size separate by hundreds of dollars per square foot. You control this with your selections.
02
Lot and sitework
Slope, soils, access, and utility distance decide how much you spend before framing starts. A flat, serviced lot is cheap to build on. A steep lot with retaining walls, deep footings, and a long driveway can add six figures of sitework.
03
Architecture and structure
Square footage is only part of the cost. Tall ceilings, long open spans, multiple rooflines, large glass, and complex geometry all add structure, labor, and material. A simple rectangle is far cheaper per foot than a sculptural plan.
04
Size and efficiency
Bigger homes cost more in total but often less per square foot, because the expensive rooms (kitchens, baths) are a smaller share of the whole. Bedrooms and great rooms are comparatively cheap space.
Section 03
A worked sample budget.
Here is a 4,500 sq ft premium-finish home in Washington County, broken out the way our contracts are. At $385 per square foot, the build comes to $1,732,500. The percentages show where the money goes, not a fixed quote: your selections and lot move every line.
Line item
Share
Budget
General conditions and supervision
Project management, on-site supervision, temporary power and facilities, cleanup.
8%
$138,600
Foundation and concrete
Footings, stem walls, slab, flatwork, and the structural engineering behind them.
9%
$155,925
Framing, lumber, and structure
Rough framing, trusses, beams, sheathing. Open spans and tall ceilings push this up.
16%
$277,200
Roof, windows, and exterior shell
Roofing, windows and doors, stucco or stone, the weathertight envelope.
12%
$207,900
Mechanical, electrical, and plumbing
HVAC, electrical rough and finish, plumbing, water heating, and low-voltage.
13%
$225,225
Interior finishes
Cabinetry, countertops, flooring, tile, trim, paint, and built-ins. The finish tier lives here.
22%
$381,150
Fixtures and appliances
Plumbing fixtures, lighting, hardware, and appliance packages.
7%
$121,275
Permits, plan review, and impact fees
Building permit, plan check, and municipal impact fees. Set by your city, not by us.
5%
$86,625
Builder overhead and margin
What keeps the company solvent, insured, bonded, and standing behind the 2-year warranty.
8%
$138,600
Total build cost (4,500 sq ft)
100%
$1,732,500
This total is build cost only. Add the lot, geotechnical and civil engineering, landscaping, any pool, and financing costs from Section 05 to reach your all-in number.
Section 04
Custom vs spec.
A spec, or new construction, home is built from a standardized plan with fixed selections, which is why it costs less per square foot. A custom home is designed for your lot and your selections, with the finish level you choose. Both are real options. The right one depends on how much you want to control.
At $260 per square foot, our spec homes start meaningfully below a Standard-finish custom build at $305. The premium buys design flexibility, finish choice, and a home shaped around your site rather than a catalog.
Spec / new construction
Standardized plan and selections
$260
Custom, Standard finish
Designed for your lot
$305
Custom, Premium finish
Designer-grade throughout
$385
Custom, Luxury finish
Fully bespoke
$525+
Build cost per square foot, Washington County, before lot and county adjustments.
Section 05
Soft costs people forget.
The per-square-foot build number is not the whole picture. These line items sit outside the build cost and quietly reshape a budget when they are not planned for. None of them are included in the figures above.
The lot itself
Land is quoted separately and varies enormously by city and view. Budget it as its own line, not folded into the build number.
Geotechnical and civil engineering
Soils reports, grading and drainage plans, and structural engineering. Required on most lots and easy to forget when you are focused on the house.
Design and plan review
Architectural design, interior design, and HOA or design-committee review in planned communities. Allow time as well as money here.
Landscaping and hardscape
Yards, walls, patios, and irrigation are quoted separately. In Southern Utah, water-wise landscaping is both a budget and a code consideration.
Pools and outdoor living
A pool, casita, or outdoor kitchen is its own project with its own permit. Plan it early so the site work and utilities are stubbed for it.
Financing and carrying costs
Construction loan interest, inspections, and the gap before your permanent mortgage. Real money over a 10-to-14-month build.
Section 06
County differences.
Washington County (St. George, Ivins, Hurricane, Washington) is our baseline. Iron County (Cedar City) runs about 15 percent lower on labor and lots. Kane County (Kanab) runs about 8 percent lower, with a smaller discount because remote logistics offset some of the savings.
Washington County
$1,732,500
4,500 sq ft, premium finish
Our baseline market.
Iron County
$1,472,625
4,500 sq ft, premium finish
About 15 percent below the Washington County baseline.
Kane County
$1,593,900
4,500 sq ft, premium finish
About 8 percent below the Washington County baseline.
A Cedar City build of this size lands near $1,472,625 on the same finish, before lot and sitework.
Section 07
Where to save without regret.
Smart savings
- Right-size the plan before you add finish. A tighter, well-designed footprint saves more than any single material swap.
- Spend the finish budget where you touch it daily: kitchen, primary bath, main flooring. Pull back in secondary bedrooms and the garage.
- Choose timeless, mid-grade materials over trend-driven luxury that dates in five years and costs more to install.
- Keep the structure simple. A clean roofline and rectangular footprint free up budget for the finishes you actually see.
- Lock selections early. Late changes carry change-order pricing and schedule cost, not catalog pricing.
False savings
Cheaper now, costlier later
- Cutting insulation, windows, or HVAC. You pay it back in utility bills and comfort for the life of the home.
- Skipping geotechnical work or proper drainage to save upfront. Soil and water problems are the most expensive things to fix later.
- Under-building the electrical and low-voltage rough-in. Adding circuits and runs after drywall is far more expensive than during framing.
- Choosing the lowest bid without reading the allowances. A low number with thin allowances is a high number waiting to happen.
Section 08
Questions to ask any builder.
Ask these of anyone you are considering, including us. Honest answers tell you more than the bottom-line price.
01
Is this a fixed price or a cost-plus contract, and what is in the allowances?
A low headline number with thin allowances grows after you sign. Ask for the allowance schedule line by line and compare apples to apples.
02
What is included, and what is quoted separately?
Confirm whether the number includes the lot, sitework, landscaping, and pool, or just the build. Most build figures exclude those.
03
Are you licensed, insured, and bonded, and what warranty do you provide?
Ask for the license number, proof of insurance, and the warranty terms in writing. Casteca is licensed Utah GC 14205355-5501, insured and bonded, with a 2-year warranty.
04
How do change orders work, and how are they priced?
Understand how mid-build changes are quoted and approved before you start, so a few selection changes do not quietly reshape the budget.
05
What does your draw schedule and timeline look like?
A clear draw schedule tied to real milestones, and an honest timeline, tell you more about a builder than the bottom-line price does.
For context, established custom builders in Southern Utah generally run $450 to $700 per square foot, carrying a name-brand premium and higher overhead. As a new builder, we price below that range on purpose, and we would rather earn the comparison than hide from it.
Done reading? Run your own numbers.
Turn this into
a real budget.
The cost estimator turns these ranges into a live number for your square footage, finish level, and city. A discovery call turns that into a real budget for your specific lot.