BuildGrade Guide

What Does It Cost to Build Contractor Bays or Flex Space?

Shell flex space runs $44–$62/sqft. Standard vanilla shell runs $58–$80/sqft. Finished space with office and HVAC runs $76–$108/sqft. Those numbers only tell part of the story — paving, HVAC, office buildout, and parking can add 30–50% on top of the shell.

By Alex Wright · Updated June 2026 · 12 min read

Shell Only

$44–$62/sqft

bare structure, no HVAC or finishes

Standard Finish

$58–$80/sqft

insulated, lit, 3-phase, tenant-ready

With Office + HVAC

$76–$108/sqft

20–25% office component, full finishes

Run the Numbers in the Calculator Self-Storage Facility Cost Guide →

Use this guide if:

✓You’re evaluating a flex space or contractor bay development
✓You need realistic build cost assumptions for a pro forma
✓You plan to model the project in DealForge or with a lender

Skip this guide if:

✗You need residential garage or shop pricing
✗You’re estimating a renovation or interior retrofit

Finish Level: The Biggest Cost Lever

Finish level determines the majority of per-sqft cost before any other decision is made. Understand what each level includes before pricing your project.

Shell

Lowest Cost

$44–$62/sqft

Included

Steel frame, metal panels, concrete slab, basic electrical rough-in, overhead doors, and man doors. No insulation, no HVAC, no interior finishes.

Not Included

Insulation, HVAC, interior framing, plumbing, office space, paint

A 10-bay, 18,000 sqft building runs $790K–$1.1M shell-only

Best for: Tenants who will build out their own space; light industrial users; owner-operators who want to grow into the space over time

Vanilla Shell (Standard)

Most Common

$58–$80/sqft

Included

Everything in shell plus insulated panels or liner, LED lighting throughout, 3-phase electrical service to each bay, basic restroom (1 per 5 bays typical), and tenant-ready overhead doors.

Not Included

Office buildout, HVAC beyond office area, specialized plumbing

A 10-bay, 18,000 sqft building runs $1.04M–$1.44M at standard finish

Best for: Multi-tenant flex parks; landlord seeking market-rate NNN leases with minimal TI; contractor bay rentals

Finished (Office-over-Warehouse)

Highest Value

$76–$108/sqft

Included

Standard shell plus finished office component (20–30% of total SF), full HVAC in office, insulated warehouse, upgraded lighting, separate utility meters per unit, and paved parking.

Not Included

Tenant-specific buildout beyond standard office, specialty utilities

A 10-bay, 18,000 sqft building with 25% office runs $1.37M–$1.94M finished

Best for: Higher-rent flex markets; users who need office + warehouse in one unit; small business parks; medical distribution or pharmaceutical flex

Full Project Cost Breakdown

The shell number in a quote often excludes 30–50% of total project cost. Here’s every major component.

Building Shell (Frame, Slab, Panels, Doors)

45–60% of total

Steel pre-engineered frame on a reinforced concrete slab, metal wall and roof panels, sectional overhead doors (one per bay standard), and man doors. The primary cost lever is finish level — shell vs. standard vs. finished spans a 2× range per sqft.

HVAC

8–15% of total

Office-only HVAC (heating and cooling for the office component) adds roughly $6/sqft averaged over the entire building. Full-building HVAC (warehouse + office) adds $14/sqft. Most flex tenants heat the warehouse with gas unit heaters and cool only the office — budget accordingly.

Office Buildout

5–15% of total

Finished office space at $55/sqft premium over the shell rate — interior framing, drywall, insulation, lighting, HVAC drops, and basic finishes. At 20% office (3,600 sqft of an 18,000 sqft building), this adds roughly $198,000 to the project.

Paving (Parking, Drive Aprons, Fire Lanes)

10–18% of total

Asphalt parking and maneuvering area sized for one parking stall per 200–300 sqft of flex space (local code varies) plus 50 ft aprons in front of each overhead door for truck access. Budget 1.5× building footprint in paved area at $5.25/sqft.

Site Utilities (Service, Trenching, Meters)

4–7% of total

3-phase electrical service to the building (required for most industrial tenants), individual sub-metering per bay, gas service, and water/sewer connections. Budget $30,000–$45,000 for a standard 10-bay building; multi-tenant configurations with separate meters run higher.

Permits, Engineering & Soft Costs

2–4% of total

Building permits, structural engineering, civil drawings for parking and drainage, and inspection fees. Commercial flex is straightforward to permit in most jurisdictions; 2.5% of hard cost is a reliable planning number.

Model your specific configuration

The flex space calculator lets you set bay count, dimensions, finish level, HVAC, office percentage, and region — then shows a line-item cost breakdown and projected rent income.

Bay Configuration: Dimensions and Clear Height

Bay dimensions drive leasability more than almost any other design decision. Getting these wrong is expensive to correct after the fact.

Dimension	Typical Range	Notes
Bay width	24–30 ft	30 ft is the de facto standard for contractor bays. Narrower bays (24 ft) work for lighter users but limit vehicle access and equipment storage. Wider bays (40 ft) command premium rents but require deeper buildings to keep proportions right.
Bay depth	40–60 ft	50 ft depth is the most versatile — fits most trucks, trailers, and equipment. 40 ft works for light contractors and auto users. 60 ft is preferred for heavy equipment, semi-truck access, or RV/boat storage with an enclosed component.
Clear height	14–18 ft eave	14 ft clear is the minimum for most industrial use. 16–18 ft clear opens the space to more tenants and commands 10–15% rent premiums. The incremental cost of going from 14 ft to 16 ft clear is modest ($1–$2/sqft) — almost always worth it.
Overhead door size	12×14 ft standard	12 ft wide × 14 ft tall is standard. 14×14 accommodates larger trucks and equipment. Roll-up doors (not sectional) are preferred for very heavy use — they tolerate more abuse and don't require headroom clearance.

Rule of thumb: Build to 30 ft wide × 50 ft deep at 16 ft clear height as your default. This configuration serves the broadest tenant mix — contractors, service vehicles, equipment dealers, light distributors — and is the easiest to lease and refinance.

Office Percentage: How Much to Build

The fraction of total building SF dedicated to office affects cost, rent rate, tenant mix, and cap rate. More office isn’t always better.

0% office — Pure storage / light industrial

Lower $/sqft

Maximum warehouse area. Works for storage users, auto, landscaping. Fewer tenants qualify, limiting your lease-up options.

10% office — Light contractor / trades

Market rate

One small office per bay or shared office per building section. Most common in pure contractor bay parks.

20–25% office — Contractor + small business flex

Premium

The sweet spot for multi-tenant flex parks. Broadens the tenant pool significantly — HVAC/plumbing contractors, distributors, light manufacturing.

30%+ office — Office-warehouse hybrid

Highest $/sqft

Commands the highest rents per sqft. Limits tenant pool to businesses that actually need significant office — reduces speed of lease-up in industrial markets.

See how finish level and office % move the numbers.

The calculator models building cost and projected rent income together — adjust bay count, finish, HVAC, and office percentage to find your configuration.

Open Calculator →

HVAC Options and What They Cost

HVAC is one of the most consequential decisions in flex space development. Overcooling costs money you won’t recover; underproviding limits your tenant pool.

No HVAC (shell only)

Most common for pure contractor bay builds. Tenants add their own gas unit heaters. Works in moderate climates; difficult to lease to office-using tenants.

+$6/total sqft

Office HVAC only (partial)

Heat and cool the office component only; tenant handles warehouse. Standard for 10–25% office configurations.

+$14/total sqft

Full building HVAC

Conditioned warehouse space. Required for pharmaceutical, food, and some light manufacturing tenants. Commands significant rent premium but limits tenant pool to those who actually need it.

Cost add is per sqft of total building area at national average. Regional multipliers apply.

Parking Requirements

Parking is one of the most frequently underestimated cost items in flex space development — and one of the most common site selection mistakes.

Typical requirement: 1 stall per 200–300 sqft of flex space

An 18,000 sqft, 10-bay building at 1:250 requires 72 parking stalls. At a typical stall size of 300 sqft (9×33 ft including drive aisle), that’s 21,600 sqft of paved area just for parking — larger than the building footprint of a 5-bay configuration. At $5.25/sqft paved, that’s over $113,000 in parking lot construction alone.

Industrial zoning vs. commercial zoning

Flex space is sometimes permitted under industrial zoning (lighter parking requirements, often 1:500–1:1,000 sqft) or commercial zoning (heavier requirements). Know which zoning classification applies to your site before designing. The wrong zoning classification can add 30–50 stalls to the parking requirement.

Truck apron depth in front of overhead doors

50 ft semi-trucks need a clear maneuvering depth of 80–90 ft in front of overhead doors. In a drive-through configuration (doors front and back), you need 80+ ft of clear space on each side of the building. On a constrained site, this can limit your building footprint significantly — account for it during site selection.

Regional Cost Variation

Region	Multiplier	Notes
Northeast / Pacific Coast	1.20–1.45×	High labor and permit costs. Flex space in demand near port, logistics, and distribution corridors.
Chicago Metro / Mid-Atlantic	1.10–1.30×	Strong industrial demand. Union labor applies to commercial construction over threshold size in many jurisdictions.
Mountain West / Midwest	0.90–1.10×	National average range. Strong contractor availability for metal building construction.
South	0.85–1.05×	Competitive labor market and high demand growth. Texas and Florida industrial markets have tightened significantly.
Plains & Gulf Coast	0.80–0.95×	Lowest build costs. Industrial demand more limited outside of agricultural and energy-related corridors.

Multipliers vs. national average. Applied automatically in the calculator based on state selection. See the full regional variation guide →

Hidden Costs That Surprise First-Time Developers

$15,000–$50,000

Parking ratio compliance

Most zoning codes require 1 stall per 200–300 sqft of flex space. A 10-bay, 18,000 sqft building may require 60–90 parking stalls. Parking lot construction cost can rival the building shell in tight sites.

$8,000–$25,000

3-phase electrical service upgrade

Many rural sites and older suburban areas don't have 3-phase power at the property line. Utility upgrade cost is unpredictable — get a quote from the local utility before closing on land.

$3–$6/sqft

Fire suppression (sprinkler system)

Required in most jurisdictions for commercial buildings above a threshold size (often 12,000 sqft). On an 18,000 sqft building, this adds $54,000–$108,000.

$10,000–$30,000

Truck apron and turning radius

50 ft semi-trucks need 80–90 ft of clear maneuvering depth in front of overhead doors. On a constrained site, providing this depth requires either a smaller building or expensive retaining walls and grade changes.

$1,500–$3,500 per bay

Separate utility meters per tenant

Required for NNN leases where tenants pay their own utilities. On a 10-bay building, this adds $15,000–$35,000 to the electrical scope.

3–5% of project cost

Construction loan carry cost

Flex space typically takes 9–15 months from groundbreaking to full lease-up. At current commercial lending rates, carry cost adds meaningfully to total project cost.

Common Mistakes in Flex Space Development

❌

Undersizing bay depth for the tenant base

40 ft deep bays seem cost-effective but limit tenants to light users. A contractor who needs to pull a truck with a trailer inside needs 60 ft minimum. Go 50 ft at minimum — the incremental slab cost is modest, the tenant pool difference is significant.

❌

Building at 14 ft clear height to save cost

The steel cost difference between 14 ft and 16 ft eave clear is roughly $1/sqft. The rent difference is 10–15%. Almost every underwriter and tenant prefers 16 ft clear. Design to 16 ft minimum; consider 18 ft in markets with significant equipment storage demand.

❌

Ignoring parking ratio requirements during site selection

Industrial zoning often requires more parking than it looks like on paper. Verify the parking ratio requirement with the local zoning office before buying land — a site that looks like it can fit 20 bays may only support 14 after parking is satisfied.

❌

No sub-metering budget for multi-tenant buildings

NNN leases require tenants to pay their own utilities. This requires individual meters per bay. Budget $1,500–$3,500 per bay for electrical sub-metering and verify water/gas metering requirements with the local utility.

❌

Underestimating HVAC for office component

A 20% office on an 18,000 sqft building is 3,600 sqft of conditioned space. The HVAC system, ductwork, and electrical for that office adds $50,000–$80,000. This is often left out of early estimates because it's not part of the 'shell' quote.

❌

Pricing the project at full HVAC when tenants only need partial

Full building HVAC adds $14/sqft vs. $6/sqft for office-only. On an 18,000 sqft building that's a $144,000 difference. Unless your target tenant requires a conditioned warehouse, partial HVAC is almost always the right call for flex space.

Next Step

Model your configuration before talking to contractors

The flex space calculator lets you set bay count, dimensions, finish level, HVAC, and office percentage — then outputs a line-item cost breakdown and income projection. From there, export to DealForge for a full deal analysis.

Open Flex Space Calculator →Self-Storage Build Costs →

Related Calculators & Guides

→Flex Space Cost Calculator →Self-Storage Cost Calculator →Self-Storage Facility Cost Guide →Regional Cost Variation Guide →Metal Building Calculator →Concrete Slab Cost Guide

Frequently Asked Questions

How much does it cost to build a contractor bay or flex space building?

Shell-only flex space runs $44–$62/sqft. Standard vanilla shell (insulated, lit, tenant-ready) runs $58–$80/sqft. Finished space with office buildout and HVAC runs $76–$108/sqft. A 10-bay, 18,000 sqft contractor bay building at standard finish typically costs $1M–$1.5M including paving and site utilities. See the full breakdown above for each cost component.

What is the difference between shell and vanilla shell for flex space?

A shell is the bare structure — steel frame, slab, panels, overhead doors, basic electrical rough-in. Nothing tenant-ready. A vanilla shell adds insulated panels or liner, LED lighting throughout, 3-phase electrical service to each bay, and a basic restroom. Vanilla shell is the standard for multi-tenant flex parks — it's what most tenants expect when they say 'move-in ready.' Shell delivery is typically reserved for owner-occupied builds where the owner plans to customize the space themselves.

What bay dimensions should I build for contractor use?

30 ft wide × 50 ft deep at 16 ft clear height is the de facto standard for contractor bay construction. This accommodates most service trucks, box trucks, and equipment trailers. Narrower bays (24 ft) limit the tenant pool; shallower bays (40 ft) exclude trailer-towing users. The incremental cost of going from 24×40 to 30×50 at 16 ft clear is modest relative to the improvement in leasability.

How much does HVAC add to flex space build cost?

Office-only HVAC adds roughly $6/sqft averaged over the total building area. Full building HVAC (warehouse + office) adds $14/sqft. On an 18,000 sqft building, that's $108,000 vs. $252,000 — a $144,000 difference. Most contractor bay and flex parks heat the warehouse with gas unit heaters (tenant-installed) and HVAC only the office component. Full building conditioning is typically reserved for pharmaceutical, food, or precision manufacturing tenants.

What is a realistic return on flex space development?

Stabilized cap rates for flex/industrial space have compressed to 5.5–7.5% in most markets. Development yields (stabilized NOI / total cost) for well-executed flex projects typically run 7–10%, implying a 150–250 basis point development spread. Lease-up timing is critical — most flex parks reach 85%+ occupancy within 12–18 months of delivery in supply-constrained markets. Use the calculator to model income, then run a full IRR and DSCR analysis in DealForge before committing.

What office percentage is standard for flex space?

10–25% office is the standard range for multi-tenant flex parks. 10% is common for pure contractor bay builds where tenants primarily need warehouse access. 20–25% broadens the tenant pool to distributors, service businesses, and light manufacturers who need meaningful office space alongside the warehouse. Anything above 30% is typically marketed as office-warehouse rather than flex industrial.

How does regional location affect flex space build cost?

Labor cost variation drives most of the regional spread — the same building costs 25–45% more in the Northeast than in the Plains states. See the regional table above for multipliers. Beyond labor, local code affects parking ratio requirements, fire suppression thresholds, and utility connection processes — all of which can significantly affect total project cost independent of the building itself.