Types of Solar Mounting Systems: A Practical Selection Guide

Choosing a solar mounting system is not simply a matter of deciding whether the panels will be installed on a roof or on the ground.

The installation surface is only the first decision. Module dimensions, roof structure, soil conditions, wind and snow requirements, tilt angle, available space, foundation method, access for construction equipment, and long-term maintenance can all change the final mounting configuration.

This guide explains the main types of solar mounting systems, how they are classified, and which engineering inputs should be reviewed before selecting a system.

Table of Contents

Quick Answer: What Are the Main Types of Solar Mounting Systems?

Solar mounting systems are most commonly grouped by where the PV array is installed:

Roof mounting systems for pitched and flat roofs
Ground mounting systems using fixed-tilt or tracking structures
Solar carports installed above parking areas
Agrivoltaic mounting systems designed to share land with agriculture
Balcony mounting systems for small distributed PV applications

Other specialized systems include pole mounts, façade or building-integrated PV, in-roof systems, and floating solar.

However, installation location is only one way to classify solar mounting. The same project can also be classified by structural behavior, attachment method, or foundation type.

The U.S. Department of Energy similarly treats rooftop PV, ground-mounted PV, and carport PV as project types with different structural and site considerations.

Solar Mounting System Types at a Glance

Mounting Type	Typical Installation	Main Structural Interface	Key Engineering Question
Pitched Roof	Metal, tile, shingle roofs	Roof attachment + rail/direct support	How will loads transfer into the roof structure?
Flat Roof	Commercial and industrial roofs	Ballast and/or mechanical attachment, concrete foundation	Can the roof support the system and resist wind uplift?
Fixed-Tilt Ground Mount	Open land	Piles, ground screws , concrete or ballast	Which foundation suits the soil and structural reactions?
Tracking Ground Mount	Large ground projects	Foundation + moving tracker structure	Does the energy benefit justify mechanical and O&M complexity?
Solar Carport	Parking areas	Foundations + columns + canopy	How will PV geometry coordinate with vehicles and drainage?
Agrivoltaic	Agricultural land	Foundations + elevated structure	What clearance and spacing(GL) are required for continued agricultural use?
Balcony Mount	Balcony, railing or wall	Compact structural attachment	Can the railing or supporting structure safely carry the system loads?

There is no single mounting type that is automatically best.

The suitable system is the one that matches the site, supporting structure, module layout, environmental loads installation conditions and cost budget.

How Are Solar Mounting Systems Classified?

A useful solar mounting classification should distinguish between three different questions.

1. By Installation Location

The first question is where the PV array will be installed:

Building roof
Open ground
Parking area
Agricultural land
Balcony or façade
Water surface
Other specialized structures

This normally determines the basic mounting family.

2. By Structural Behavior

The second question is how the modules are positioned during operation.

Fixed Mounting

The modules remain at a predetermined tilt and orientation.

Most rooftop systems, carports, agrivoltaic structures and many ground-mounted systems use fixed structures.

Adjustable Mounting

The adjustable solar mounting systems allow for manual tilt angle adjustment within a specified range.

Tracking Mounting

The tracking structures automatically move the PV modules throughout the day to follow the sun.

Single-axis trackers are widely used in utility-scale PV where the site, economics and operating strategy support the additional mechanical equipment.

DOE notes that ground-mounted arrays may use tracking mechanisms to follow the sun and increase energy capture, while NREL data also shows the importance of single-axis tracking in utility-scale PV deployment.

3. By Attachment or Foundation Method

A third classification describes how structural loads are transferred.

Examples include:

Mechanical roof attachments
Ballasted roof mounting
Driven piles
Ground screws
Concrete foundations
Direct structural connections
Hybrid ballast and mechanical attachment

This distinction is important because mounting type and foundation type are not the same decision.

For example, two fixed-tilt ground systems may use completely different foundations because of different soil conditions.

What Actually Determines the Mounting System?

Before looking at individual product types, it is more useful to understand the engineering inputs that change the mounting configuration.

Solar Mounting Selection Matrix

Project Input	What It Can Affect
Installation environment	Basic mounting family
Roof profile	Roof attachment method
Roof structural member	Attachment position and load transfer
Module dimensions	Rail length, clamp position and table geometry
Module orientation	Structural layout and component quantities
Wind design input	Member sizing, spacing, attachments and foundations
Snow requirement	Structural members, spacing and tilt considerations
Soil condition	Ground foundation concept
Tilt angle	Structural geometry and support height
Terrain	Foundation installation and table arrangement
Parking layout	Carport column locations and spans
Agricultural machinery	Agrivoltaic clearance and row spacing
Corrosion environment	Material and surface-treatment requirements
Installation access	Rail lengths, equipment requirements and assembly strategy
Maintenance access	Row spacing and service clearances

This is why selecting a mounting system from a product photograph alone is rarely enough for an engineering project.

1. Roof Solar Mounting Systems

Roof solar mounting systems use an existing building as the primary supporting structure.

The first question should therefore not be:

Which solar bracket should I use?

It should be:

What roof and structural interface are we attaching to?

DOE recommends evaluating rooftop PV based on roof compatibility, structural strength, roof condition and wind exposure.

Pitched Roof Mounting

Pitched-roof PV generally follows or remains close to the existing roof slope.

A typical system may include:

Roof attachments
Aluminum rails or short mounting profiles
Mid clamps
End clamps
Rail clamps
Rail connectors
Fasteners
Grounding components

The exact attachment depends on both the roof covering and the structural member below it.

Metal Roof Mounting

“Metal roof” is not one mounting condition.

Different profiles may require different interfaces.

Trapezoidal or Corrugated Metal Roof

Depending on the roof profile and structural arrangement, possible mounting interfaces may include:

L feet
Hanger bolts
Short or mini rails
Profile-specific brackets
Adjustable or elevated support structures where required

The mounting method should be selected from the actual roof cross-section and structural support, not simply from the description “metal roof.”

Standing-Seam Roof

Compatible standing-seam roofs can use seam clamps that grip the seam without penetrating it.

The clamp geometry must match the actual seam profile.

Additional rail or support structures can then be connected above the seam clamp according to the required module configuration.

The standing-seam roofs can also utilize the standing seam clamp and L feet mounting solution.

Tile Roof Mounting

Tile-roof systems commonly use roof hooks or structural attachments connected to the load-bearing structure below the roof covering.

The design needs to coordinate:

Hook position
Structural connection
Tile clearance
Rail direction
Waterproofing details
Module layout

The roof covering itself should not be treated as the primary structural attachment.

Shingle Roof Mounting

Shingle-roof systems normally transfer loads to rafters or another suitable structural element.

Flashing and waterproofing details are particularly important where the mounting system penetrates the roof envelope.

Flat Roof Solar Mounting Systems

Flat and low-slope roofs usually require the mounting structure itself to create the module tilt.

Two broad approaches are commonly used.

Ballasted Mounting

Ballasted systems use added weight as part of the resistance against movement and wind uplift.

Their main advantage is that roof penetrations can sometimes be reduced.

However, ballast adds dead load to the building, so roof structural capacity must be reviewed.

The U.S. Department of Energy describes ballasted racking as a common commercial flat-roof approach and notes that the amount of ballast and mechanical attachment depends on roof capacity and wind-load requirements.

Mechanically Attached Mounting

Mechanically attached systems transfer loads into the roof or building structure through structural attachment points.

This may reduce ballast requirements but introduces roof penetrations that must be properly detailed and sealed.

Hybrid Systems

Some flat-roof projects combine ballast with selected mechanical attachments.

This is why the practical decision is not simply:

Ballasted or attached?

The engineer needs to consider:

Roof structural capacity
Wind exposure
Waterproofing
Attachment restrictions
Roof membrane
Module layout
Available ballast
Local design requirements

DOE severe-weather guidance specifically warns against treating full ballast as universally appropriate in higher wind conditions.

2. Ground Solar Mounting Systems

Ground-mounted PV creates its own supporting structure instead of relying on an existing building.

This provides greater flexibility in:

Module orientation
Tilt
Row spacing
Ground clearance
Maintenance access

But it also introduces another major engineering question:

How will the structure connect to the ground?

Fixed-Tilt Ground Mount

A fixed-tilt structure holds modules at a predetermined angle.

Typical components can include:

Foundations
Base
Posts
Main beams
Bracing
Rails or purlins
Module clamps
Structural fasteners

Because there is no daily tracking movement, fixed-tilt systems are mechanically simpler than trackers.

They can be used across commercial, industrial and utility-scale projects.

Single-Axis Tracking

A single-axis tracker rotates module rows during the day.

Additional components may include:

Torque tubes
Bearings
Drive units
Motors or actuators
Controllers
Moving module supports

Tracking can improve energy capture in suitable projects, but the decision also needs to consider:

Terrain
Project scale
Foundation requirements
Mechanical complexity
Capital cost
Operations and maintenance
Site layout

The question is therefore not simply whether tracking produces more energy.

The relevant question is whether the complete project benefits from the additional mechanical system.

Ground Foundations: Ground Screw, Driven Pile or Concrete?

The foundation should not be selected independently of the site.

Ground Screws

Ground screws use the hot-dip galvanizing steel screw-type foundations installed into suitable soil.

Potential project advantages can include:

Reduced concrete work
Fast structural connection after installation
Potential removability
Suitability for selected irregular or sloping sites

Actual suitability depends on ground conditions, engineering verification, solar panel array, GL snow load and wind speed.

Driven Piles

Driven piles are commonly used where repetitive pile installation is practical in large-scale photovoltaic panel installation site.

Foundation design still depends on:

Soil conditions
Pile section
Embedment depth
Pull-out resistance
Lateral resistance
Corrosion conditions
Installation equipment

Concrete Foundations

Concrete foundations may be considered where driven piles or ground screws are unsuitable or where the structural concept requires a different foundation interface or the PV installation site already with an existing concrete surface.

They normally involve additional:

Excavation
Formwork or precast preparation
Concrete work
Curing
Civil construction

There is therefore no universal “best” foundation for ground-mounted solar.

Real Engineering Example: One Ground Project, Multiple Mounting Configurations

A historical Easy Solar engineering project in Japan illustrates why choosing “ground mount” is only the first structural decision.

The project was approximately 316 kW and used a ground-screw foundation concept.

Project drawings listed:

PV module size: 1684 × 1002 × 35 mm
Wind design input: 30 m/s
Snow condition: 35 cm
Reference standard: JIS C 8955:2017
Multiple array/table configurations
Tilt configurations of 10°, 20° and 30°

The project did not use one identical mounting table across the entire site. Different array sizes and tilt configurations were used within the same project.

More importantly, the structural drawings stated that the final foundation specification should be determined according to geotechnical investigation or on-site testing.

Engineering Takeaway

“Ground-mounted” describes the project family, not the final structure.

Even within one site, module arrangement, tilt, table size, structural span and foundation layout can change according to the site and engineering inputs.

JIS C 8955:2017 is a Japanese standard covering load design for structures supporting photovoltaic arrays installed on the ground or on buildings.

3. Solar Carport Mounting Systems

A solar carport combines PV generation with an occupied parking canopy.

Unlike a conventional ground-mounted array, the space beneath the modules must remain usable.

Typical structural elements include:

Foundations
Base
Columns
Main beams
Bracing
Module rails or purlins
Module clamps
Drainage components where applicable

The design therefore needs to coordinate PV requirements with the parking environment.

Important inputs include:

Parking-bay dimensions
Vehicle clearance
Drive lanes
Column locations
Canopy span
Pedestrian routes
Rainwater drainage
Lighting
EV charging equipment
Service access
Wind and snow requirements

DOE treats carports separately from standard rooftop and ground-mounted PV because the occupied space below the structure introduces additional planning requirements. Its guidance specifically highlights drainage, vehicle clearance, column protection and service access.

Foundation selection should still be based on structural reactions, geotechnical conditions, existing pavement and construction requirements rather than assuming one foundation type is universally superior.

4. Agrivoltaic Mounting Systems

Agrivoltaics allows photovoltaic generation and agricultural production to share the same land.

DOE defines agrivoltaics as agricultural activity—including crops, livestock or pollinator habitat—located underneath or between rows of solar panels.

This changes the mounting structure considerably.

A conventional ground-mounted array may only require clearance for installation, vegetation management and maintenance.

Agrivoltaic structures may also need to accommodate:

Tractors
Agricultural machinery
Workers
Crops
Livestock
Irrigation equipment
Farm-access routes

As a result, the design may require:

Increased ground clearance
Different column heights
Longer structural spans
Additional bracing
Wider row spacing
Different foundation reactions

Module height, density and row spacing also affect how much light reaches the agricultural area.

DOE agrivoltaic research specifically identifies solar configuration, site layout and the ability of farm equipment such as tractors to operate around or beneath the system as important project considerations.

Agrivoltaic mounting should therefore be designed around both the PV system and the continuing agricultural activity.

5. Balcony Solar Mounting Systems

Balcony solar systems are smaller, but small size does not eliminate structural requirements.

A balcony mounting system may attach to:

Railings
Walls
Balcony floors
Other suitable supporting structures

Key inputs include:

Railing geometry
Railing material
Module dimensions
Module weight
Wind exposure
Tilt angle
Attachment geometry
Available space
Secondary safety requirements

The bracket cannot be selected only by matching its width to the railing.

The module, mounting bracket, supporting structure and environmental loads need to be considered as one mechanical system.

Other Specialized Solar Mounting Types

Several additional mounting categories exist outside the most common roof, ground, carport, agrivoltaic and balcony applications.

Pole Mounting

Pole-mounted PV supports a relatively small array on one or a limited number of structural poles.

It can be useful for:

Remote systems
Pumps
Small off-grid installations
Locations unsuitable for conventional multi-post ground arrays

Façade and Building-Integrated PV

PV can also be attached vertically to façades or integrated directly into the building envelope.

These systems introduce additional requirements related to:

Building attachment
Waterproofing
Ventilation
Fire performance
Architectural integration

In-Roof Systems

In-roof systems replace or integrate with part of the roof covering instead of simply mounting modules above it.

They should therefore be evaluated as part of the roof-envelope design rather than as conventional above-roof racking.

Floating Solar

Floating PV uses buoyant structures on reservoirs, lakes or other water surfaces.

DOE distinguishes floating PV from conventional land-based solar because the structural support, anchoring and site environment are fundamentally different.

Solar Mounting Types Compared

Factor	Roof	Ground	Carport	Agrivoltaic	Balcony
Existing structure used	Yes	No	No	No	Usually
Dedicated foundation	Usually no	Yes	Yes	Yes	Usually no
Roof review	Essential	No	No	No	Sometimes
Soil/geotechnical review	No	Often	Often	Often	No
Clearance requirement	Low	Project-specific	Vehicle clearance	Agricultural clearance	Application-specific
Main structural interface	Roof attachment	Foundation	Foundation + columns	Foundation + elevated frame	Railing/wall/floor
Typical major constraint	Roof compatibility	Soil + site geometry	Parking use	Agricultural use	Supporting structure
Installation equipment	Roof access equipment	Pile/screw/civil equipment	Often lifting equipment	Ground + agricultural access	Small-scale access
Project-specific engineering priority	Attachment + waterproofing	Foundation + layout	Clearance + canopy structure	Clearance + land use	Attachment + wind

The table should be used as a starting point—not as a final design rule.

How to Choose the Right Solar Mounting System

A practical selection process starts with the installation environment.

If the Project Is on a Roof

Identify:

Roof type
Roof profile
Roof structural member
Roof slope
Module layout
Wind exposure
Roof load capacity
Waterproofing requirements
Penetration restrictions

Then select an attachment and module-support configuration that matches those conditions.

If the Project Is on Open Land

Review:

Terrain
Soil or geotechnical conditions
Project scale
Module dimensions and layout
Required tilt
Wind and snow inputs
Foundation feasibility
Row spacing
Installation equipment
Maintenance access

Only after these inputs are understood should the project narrow down the structural and foundation options.

If the Project Uses a Parking Area

Evaluate a solar carport.

Start with:

Parking layout
Required vehicle clearance
Column locations
Structural spans
Drainage
Site circulation

Do not simply place a conventional PV ground table over a parking plan.

If the Land Must Remain Agricultural

Evaluate agrivoltaic mounting.

Machine access, crop or livestock use, clearance, row spacing and foundation locations become core design inputs.

If the Available Space Is a Balcony

Start with:

Supporting structure
Railing or wall geometry
Module dimensions and weight
Connection method
Wind exposure
Secondary safety

Wind and Snow Are Design Inputs, Not Product Labels

Solar mounting products are often advertised with generic statements such as a “maximum wind speed” or “maximum snow load.”

Those numbers should not be used as a substitute for project-specific design review.

A rooftop array, low ground-mounted table, elevated carport and high-clearance agrivoltaic structure can experience very different load conditions.

DOE severe-weather guidance emphasizes that racking frames, mechanical attachments, bracing and critical fastened joints need to be designed for site-specific weather risks.

Applicable design values should therefore be established from the project requirements and relevant local standards.

Installation and Maintenance Can Change the Mounting Decision

A structurally workable mounting system must also be practical to transport, install and maintain.

Before final selection, ask:

Can the required rail lengths be transported to the installation area?
Can installers safely access the roof?
Can pile-driving or ground-screw equipment enter the site?
Is crane access available for a carport?
Are roads wide enough for project vehicles?
Does agricultural machinery need to move below or between the arrays?
Can technicians reach modules and fasteners for future maintenance?
Can damaged modules or mounting components be replaced without dismantling large sections of the array?

These questions are often ignored in simple product comparisons, but they can materially change the final mounting configuration.

What Information Should Be Prepared Before Mounting Selection?

For a preliminary mounting review, a buyer should prepare as much of the following information as possible:

Basic Project Information

Country and project location
Application: roof, ground, carport, agrivoltaic or balcony
Planned PV capacity

PV Module Information

Module datasheet
Module dimensions
Module frame thickness
Module quantity
Portrait or landscape orientation

Site Information

For roof projects:

Roof type
Roof profile
Structural information
Roof photos or drawings

For ground projects:

Site plan
Terrain information
Soil or geotechnical information where available
Preferred or possible foundation method

For carport or agrivoltaic projects:

Required clearances
Parking or agricultural layout
Access requirements

Engineering Inputs

Applicable wind design information
Snow requirements
Desired tilt
Array layout
Relevant local standards or project specifications

Incomplete project inputs do not necessarily prevent preliminary discussion, but the final mounting configuration should not be treated as confirmed until the required engineering information has been reviewed.

Common Questions About Solar Mounting System Types

What are the main types of solar mounting systems?

The main application categories are roof-mounted systems, ground-mounted systems, solar carports, agrivoltaic systems and balcony mounting systems. Specialized applications include pole, façade, in-roof and floating PV.

What is the difference between fixed-tilt and tracking mounting?

Fixed-tilt structures hold modules at a fixed angle. Tracking structures move the array during the day and therefore add moving components, drives and controls. The choice depends on energy objectives, site conditions, project economics, installer preferences and maintenance strategy.

What is the difference between ballasted and mechanically attached roof mounting?

Ballasted systems use added weight to help resist movement and wind uplift. Mechanically attached systems transfer loads through structural attachment points. Some projects combine both approaches.

Which foundation is best for ground-mounted solar?

There is no universally best foundation. Ground screws, driven piles and concrete foundations should be evaluated according to soil conditions, structural reactions, terrain, corrosion conditions, available construction equipment and local project requirements. But the ground screw foundations and concrete foundations are very commonly used.

Is a solar carport the same as a normal ground-mounted system?

Both use dedicated foundations, but a carport creates an occupied canopy and must coordinate PV design with parking, vehicle clearance, column locations, drainage and public or maintenance access.

How do I know which solar mounting system my project needs?

Start with the installation environment, then review the supporting structure or soil, module dimensions, array layout, wind and snow inputs, tilt, attachment or foundation method, clearance requirements and installation access.

Final Takeaway

The most useful way to think about solar mounting systems is not “Which type is best?” Instead, ask: “Which structural configuration matches this specific site?”

Roof, ground, carport, agrivoltaic and balcony mounting describe the main application categories. The final design still depends on the actual project inputs—including the roof or soil, module layout, tilt, wind and snow requirements, foundations, clearances and construction conditions. That is why two projects in the same mounting category can require very different structural configurations.

Technical References

The following technical and institutional sources were used to support the definitions, engineering considerations, and mounting-system classifications discussed in this guide.

1. U.S. Department of Energy — Life Cycle of Photovoltaic Systems: Install and Commission a Photovoltaic System
Used for structural and site-related considerations for rooftop PV, ground-mounted PV and solar carports, including roof suitability, racking, foundations, vehicle clearance, drainage, maintenance access and severe-weather considerations.
View source

2. U.S. Department of Energy — Solar Photovoltaic System Design Basics
Used for the basic function of PV mounting structures and the distinction between fixed mounting and tracking systems for ground-mounted PV.
View source

3. U.S. Department of Energy — Severe Weather Resilience in Solar Photovoltaic System Design
Used for wind-resilience considerations involving racking frames, mechanical attachments, lateral bracing, foundations and critical fastened joints. It also supports the need for site-specific engineering rather than relying only on generic product wind ratings.
View source

4. Better Buildings Alliance / U.S. Department of Energy — Commercial Rooftop Solar: Frequently Asked Questions
Used for commercial flat-roof mounting concepts, particularly the distinction between ballasted, hybrid-ballasted and mechanically attached racking, and the relationship between ballast, roof structural capacity, penetrations and wind-load requirements.
View source

5. U.S. Department of Energy — Agrivoltaics: Solar and Agriculture Co-Location
Used for the definition of agrivoltaics and the principle of combining photovoltaic generation with continued agricultural activities such as crop production, livestock or pollinator habitat.
View source

6. U.S. Department of Energy — Dual-Use Photovoltaic Technologies
Used for broader dual-use PV classifications, including agrivoltaics and floating photovoltaic systems, and for distinguishing floating PV from conventional land-based mounting applications.
View source

7. National Renewable Energy Laboratory (NREL) — Solar Industry Update
Used as supporting industry data for the adoption and role of fixed-tilt and single-axis tracking systems in utility-scale photovoltaic projects. NREL reported that single-axis tracking had become the dominant mounting type in U.S. utility-scale PV installations by 2021.
View source

8. Japanese Standards Association — JIS C 8955:2017, Load Design Guide on Structures for Photovoltaic Array
Referenced in the historical Easy Solar ground-mounted engineering example. JIS C 8955:2017 provides guidance for calculating design loads for structures supporting photovoltaic arrays installed on the ground or on buildings. The Japanese Standards Association currently lists this 2017 edition as valid.
View source

Liya

Sales Manager at Easy Solar Solar Mounting Systems. With over 1o years of experience in the solar industry, I specialize in providing reliable andcost-effective mounting solutions for distributors, installers, and EPC companies. Experienced in intemational sales and commited to building long-term partnerships worldwide.