How One Place Solar Engineers for Cold Climates, Snow Loads, and Challenging Ground Conditions
Designing solar systems for commercial or agricultural installations goes beyond the selection of modules and inverters. One of the most critical—yet often underestimated—aspects of long-term performance is foundation design. Poorly planned foundations can lead to instability, heaving, misalignment, and early system failure, especially in regions with extreme temperatures, snow accumulation, or unstable soil conditions.
At One Place Solar, we approach foundation design with the same rigor as electrical engineering—because a structure is only as good as what it stands on.
In this blog, we explore how our design team tailors solar foundations for harsh environments using systems like Unirac GFT, pile foundations, and concrete anchoring, supported by code-compliant, PE-stamped structural designs.
Why Solar Foundations Matter More in Harsh Environments
In regions prone to heavy snow, deep frost, high wind speeds, or shifting soil, foundation failures can occur in multiple ways:
- Frost heave lifting or tilting the racking system
- Lateral load from snow or wind compromising anchor strength
- Water runoff or drainage issues causing erosion
- Improper embedment depth leading to loose or unstable structures
To prevent these issues, we begin with detailed climate zone analysis and soil load calculations, often referencing:
- Frost depth as defined by local building codes
- Snow load ratings from ASCE 7-10
- Soil type classification for each job site
- IBC and local AHJ requirements
Case Study: McLean, IL – Built for the Midwest’s Worst Weather
In our 246.4 kW ground-mounted solar installation for Special K Hog Farm in McLean, Illinois, we designed the foundation system to withstand:
- Low temperatures as extreme as -22°C
- Snow loads of 30 psf
- Wind loads of up to 90 mph (per IBC 2018)
- Loamy soil with moderate frost activity
This required a solution that balanced structural durability with cost-effective installation.
Why We Chose Unirac GFT with Pile-Driven Foundations
For this project, we selected the Unirac Ground Fixed Tilt (GFT) system, mounted on C-pile driven steel foundations, based on the following advantages:
1. Adaptability to Soil Conditions
Pile-driven foundations offer flexible embedment depth—essential in soil where frost depth and compaction vary. In McLean, we drove steel piles below the regional frost line to ensure long-term racking stability.
2. No Need for Excavation or Concrete (In Most Cases)
Unlike ballasted systems that require large concrete blocks, the GFT system allowed for faster installation with minimal site disruption.
3. High Wind and Snow Load Ratings
Unirac GFT systems are tested to handle wind uplift, snow compression, and torsional loads—backed by stamped structural calculations that we include in every permit design package.
4. Ease of Customization
We adjusted the tilt angle to 30 degrees and the azimuth to 180° (due south) to optimize year-round performance while minimizing snow buildup and shadowing.
When We Use Concrete Anchoring
While pile-driven systems are ideal for most conditions, there are certain situations where we switch to concrete anchoring methods, especially when:
- Soil has very low bearing capacity (e.g., sand or fill)
- The site is on rocky terrain, where piles cannot be driven
- There is a need for non-penetrating solutions (e.g., near buried utilities or in restricted zones)
In such cases, we provide:
- Pad footing designs with steel anchor bolts
- Ballasted foundation specs with wind tunnel data
- Reinforcement plans for concrete pour-in-place options
All our foundation designs include IBC-compliant calculations and are PE-stamped for the state where the project is located.
What’s Included in Our Solar Foundation Design Service
When you partner with One Place Solar, here’s what we include as standard in every commercial solar permit design:
- Foundation type recommendation (pile, helical, ballast, or concrete)
- Soil load and frost depth review
- Racking layout with row spacing and tilt adjustments
- Trenching and conduit coordination with array structure
- Structural PE stamps with wind/snow calcs per ASCE 7-10 or ASCE 7-16
- AHJ and code alignment with your location’s specific design criteria
A Note on Cost and Installation Efficiency
Smart foundation design doesn’t just protect your system—it saves money. By optimizing racking orientation, embedment depth, and material choice, we help reduce:
- Excess excavation or overbuilt steel
- Redundant ballast or concrete work
- Long-term O&M issues caused by misalignment or ground shifting
Our clients frequently tell us that our engineering-led designs are easier for their field teams to build and pass inspection on the first try.
Final Thoughts: Build from the Ground Up—with Confidence
In challenging climates and unpredictable terrain, your solar foundation is your first and best defense against system failure. At One Place Solar, we bring civil, structural, and electrical engineering together to deliver robust, site-specific designs that perform for decades.
Our team ensures that every component—from the tilt angle to the pile depth—is engineered with your location and longevity in mind.
If you’re planning a solar project in a region with tough weather or soil conditions, don’t guess. Design it right from the ground up.
Contact us today to request a sample structural layout or to learn more about how we engineer commercial systems for long-term success.