Everything You Need to Know

The Complete Steel Building
Buying Guide

From choosing the right gauge to understanding your permit requirements — everything you need to make a confident buying decision.

1. Choosing the Right Steel Gauge

Steel gauge applies to two separate components of your building — the roofing and siding panels and the structural tubing (studs/framing). Lower gauge number means thicker, stronger steel.

Roofing & Siding Panels
29 Gauge
Standard / Entry Level

The standard roofing and siding panel thickness. Works well for most residential carports, garages, and storage buildings. Comes with a 40-year manufacturer warranty. The most common option across the industry.

26 Gauge
Premium / Heavy Duty

Thicker panels that hold up better in extreme weather, high-wind zones, and areas with heavy rainfall or snow. Recommended for commercial structures and any building you're making a serious long-term investment in.

Structural Tubing (Frame / Studs)
14 Gauge
Standard / Most Popular

The sweet spot for most residential and light commercial builds. Strong enough for moderate spans and typical load requirements. Our most requested frame gauge — handles the majority of applications without the added cost of 12 gauge.

12 Gauge
Premium / Heavy Duty

Thicker structural tubing for wide clear-span buildings, commercial applications, and high-load environments. Required for buildings over 40 feet wide and anything engineered for heavy wind or snow. Built to last decades.

Rule of thumb: for most homeowners, 29-gauge panels and 14-gauge tubing is the right combination. If you're building commercial, wide-span, or in a severe weather zone — upgrade to 26-gauge panels and 12-gauge tubing. The cost difference is modest. The performance difference is not.

2. Roof Styles Explained

Your roof style affects aesthetics, water drainage, snow shedding, and price. Understanding the difference saves you from making the wrong call.

Vertical Roof (A-Frame Vertical)

Panels run vertically from ridge to eave. This is the strongest roof option — water and debris shed directly off the sides rather than collecting in the seams. Required for larger structures and recommended anywhere with heavy rain or snow.

Best for: Large buildings, high-rain areas, anyone who wants maximum durability
Boxed Eave (A-Frame Horizontal)

The classic A-frame look with panels running horizontally. More economical than vertical. Water drains well but can collect debris at the seams over time. Great for standard residential carports and garages.

Best for: Standard residential use, moderate climates, budget-conscious builds
Regular Style (Rounded Corners)

The most economical option. Rounded corners where the roof meets the legs — the original carport style. Works well for basic covered parking and simple storage. Not recommended for wide spans or heavy weather.

Best for: Simple covered parking, small footprints, minimal budgets

3. Engineer Certification — Do You Need It?

Each steel structure comes with a generic set of engineer-certified drawings. These drawings verify that your building is designed to meet specific load requirements: wind speed, snow load, and dead load. Most jurisdictions require them for permitted structures.

In some cases, certain local jurisdictions may require Site-Specific Engineered Drawings. Below are some reasons why.

You will likely need site-specific engineer certification if:

  • Your county or municipality requires a building permit
  • Your structure exceeds a certain square footage (varies by jurisdiction — typically 200 sq ft)
  • You’re in a high-wind zone (coastal areas, tornado corridors)
  • You’re in a flood zone
  • You’re in seismic zone D or above
  • Your HOA requires it
  • There are no other structures on the property

All Benchmark Structures steel buildings are available with engineer-certified drawings. Contact us before purchasing and we’ll confirm what your local jurisdiction requires.

4. Permits — What to Expect

Permit requirements vary significantly by location. Some counties have no requirements for structures under a certain size. Others require permits for anything that touches the ground.

Before You Buy
  • Call your county building department
  • Ask about setback requirements from property lines
  • Confirm if HOA approval is needed
  • Ask if site-specific engineer-stamped drawings are required
What We Provide
  • Engineer-certified drawings upon request
  • Anchor specifications and load ratings
  • Guidance on permit application process
  • Support from our team throughout the process

5. Foundation Options

Your building must be installed on a firm, level surface. The right foundation depends on your budget, building size, and intended use.

Concrete Slab

The gold standard. Provides maximum stability, easiest to maintain clean inside, required for fully enclosed garages in most jurisdictions.

Best for: Enclosed garages, workshops, commercial builds
Compacted Gravel

A popular and cost-effective alternative. Provides good drainage and a firm base. Must be properly leveled and compacted before installation.

Best for: Carports, open-sided structures, equipment storage
Asphalt / Dirt

Can work for simpler open structures with proper ground anchoring. The site must be level within 6 inches. Not recommended for fully enclosed buildings.

Best for: Simple open carports, temporary structures

6. What to Expect on Delivery Day

1
Site Prep

Your site must be cleared, level, and accessible before the crew arrives. Remove any debris, vehicles, or obstacles. The crew needs at least 3 feet of clearance on all sides.

2
Installation

Our certified crew builds the structure on-site. Most jobs are completed in a single day. Larger commercial buildings may take two days. You don't need to be present but someone should be available to answer questions.

3
Telescoping Lift

Any unit 25ft to 60ft wide with double legs, or any unit with a leg height over 15ft, requires a telescoping lift for installation. This equipment allows the crew to safely set and secure the roof and frame at height. If your building falls into either of these categories, confirm lift access to your site before delivery day.

4
Walk-Through & Sign-Off

Once the build is complete, do a walk-through with the crew. Inspect all panels, doors, and anchoring. Any issues are addressed before the crew leaves. You sign off confirming the job is complete to your satisfaction.

Ready to Get Started?

Our team has walked thousands of customers through this process. Contact us or request a quote and we'll help you spec out exactly what you need.

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