Guide for Mounting Solar Panels on Roof of RV

Mounting solar panels on your RV roof can greatly improve your off-grid adventures, offering a sustainable power solution no matter where you travel.

However, due to factors like sunlight exposure, the curvature of the RV roof, and its load-bearing capacity, it's essential to consider different environmental conditions.

In this detailed guide, we'll delve into diverse methods for mounting solar panels on an RV roof, offering clear, step-by-step instructions for a seamless installation.

 

 

How off-grid RV systems work?

Off-grid setups offer the freedom to light your space, preserve food, and power diverse devices independently from traditional electricity sources or shore power.

Unlike grid-tied systems, off-grid renewable energy operates autonomously from local utility services. Solar setups stand out as the preferred and most compatible off-grid power solution for RVs. An RV off-grid solar system typically includes:

• Solar panels
• Solar charge controller
• Solar batteries
• DC to AC Inverter

This article focuses on mounting solar panels on an RV roof, without delving into component selection. However, here we provides guidelines for designing a solar system:

• How to choose the best inverter for off grid solar system
• Complete Solar Charge Controller Choosing Guide - Type & Size
• How many batteries for my solar system

Furthermore, we recommend the PowMr 30amp MPPT charge controller for dual battery setups. It's proficient in solar charging and managing charging between the Starter Battery and Service Battery, utilizing BVS (Battery Voltage System) detection. Easily tailor the charging priority by adjusting the voltage threshold to your preference.

 

What is the best way to mount solar panels on an RV?

When it comes to mounting solar panels on an RV, there are several options to consider, including fixed, flexible, and tilt mounting. Each method offers its own set of advantages and considerations, depending on your RV's roof shapeand typical off-grid adventure environment.

Fixed Mounting

Engineered for durability, fixed mounting systems are designed for rigid solar panels. They require drilling holes on the RV roof, followed by the installation of mounting brackets to securely affix the panels in a flat position atop the fixed mounting system.

Flexible Mounting

Adapted to the contours of the RV roof, flexible solar panels, such as thin-film ones, simplify installation. These panels are attached using adhesive tape to achieve the desired position, minimizing the need for drilling holes. However, a single hole may still be necessary to route cables into the RV.

If your RV or van has a curved roof, PowMr flexible solar panels, capable of flexing up to 258 degrees, are the optimal choice to conform perfectly to its unique shape.

Tilt Mounting

Departing from a flat orientation, tilt mounting involves installing solar panels at an angle. This is achieved through a tilting platform, enabling adjustment of the panel angle for optimal sunlight exposure. By enhancing light absorption, this mounting method increases power output.

 

How to mount solar panels on RV roof

For detailed installation guidance, proceed with the following step-by-step instructions.

Step1 - Measure the Roof and plan the solar panel layout

Before installing, mapping out the layout allows you to envision their placement and identify where support struts should go. When linking multiple panels, ensure to maintain a gap of approximately 20 mm between them.

Arrange your solar panels on the RV roof and use colored tape to indicate their positions, steering clear of spots where shade from a satellite dish or air conditioner might fall.

In addition to allowing space between boards for heat dissipation, make sure to consider the footprint of any fixed brackets needed for installation to ensure adequate mounting space.

 

Step2 - Removal of obstacles

Consider removing any obstacles from your RV, like TV aerials or satellite dishes. Mounting them on the roof will ensure your solar panels receive maximum sunlight exposure without hindrance.

Many DIYers have vehicles with roof racks. They can bolt rigid panels onto existing racks or customize racks for the panels. Crafting custom racks with predetermined bolt locations is ideal. If unable to install, remove the rack.

 

Step3 - Clean and seal of roof integrity

Please inspect for tears, holes, cuts, and soft spots in the EPDM (rubber) roofing material, repairing any damaged areas. Addressing these issues becomes challenging once the panels are installed. Remove any damaged sections diligently and replace them with material of comparable quality. However, it's best not to use insulation material unless there's ample space for heat dissipation between the solar panels and the roof.

 

Step4 - Mount the solar panels

Mounting solar panels onto your RV roof requires careful consideration of the panel type and installation method. Whether you're dealing with flexible or rigid panels, each option comes with its own set of challenges and solutions. Here's a comprehensive guide to the three primary installation methods:

Option1. Mounting Flexible solar panels on RV roof

Flexible solar panels match rigid counterparts in output but weigh less and conform better to contours, even fitting RV roofs without drilling. Yet, adhesive installations pose risks. Panels absorb heat beyond photon production, requiring dissipation. Directly affixing to insulated surfaces like RV roofs risks overheating and damage.

Here's a simple solution: use industrial-grade Velcro tape along the perimeter and back of the panels to provide space for heat dissipation while securing them to your roof surface.

Additionally, some opt to insulate flexible solar panels from RV roofs by placing corrugated plastic sheets underneath, using VHB industrial tape for attachment.

 

Option2. Fixed Mounting Rigid solar panels on the roof of RV

The installation process varies depending on the type of panels you have. Rigid panels require securing with screws, which entails drilling holes into the roof. These panels can be mounted either flat or tilted on the roof surface, but the brackets used for installation differ.

Before installing the panels, it's crucial to locate the roof crossbeams beneath the RV roof plywood. Secure the screws for fixation into these crossbeams rather than drilling into the thin plywood under the rubber roof to ensure sufficient strength to hold the panels securely in strong winds.

 

Usually, this installation method involves using Z brackets. You can choose to install the two-hole end onto the panel frame. This allows flexibility in placing roof screws at any position on the bracket to accurately hit the rafters.

Next, firmly attach the brackets in alignment with the panel placement. Seal the bracket feet and screws with Dicor lap sealant to create an airtight seal, preventing potential roof leaks. Don't forget to have a few rags handy for cleaning. Then, mount the solar panels onto the fixed hardware.

 

Option3. Tilt mounting rigid solar panel on RV roof

By tilt-mounting solar panels on the RV roof, you can keep them flat while driving or tilt them in one direction when parked. Maximizing sun exposure by positioning the panels to tilt southwards when the vehicle is parked in an ideal orientation can significantly increase solar input. However, during travel, keeping the panels close to the roof can reduce the risk of damage from overhanging tree branches.

Similar to fixed mounting, once you locate the crossbeams, you can secure the brackets and solar panels to the RV roof. The only difference is that this time, you'll need to use tilt mounting brackets. Finally, remember to seal the bracket feet and screws with Dicor lap sealant.

 

Step5 - Connect the solar panels

Once the panels are securely mounted, it's time to connect them. Depending on your setup and desired configuration, you can connect the panels in series, parallel, or a combination of both (series-parallel). Read our blog about series and parallel connections of solar panels to ensure proper wiring and insulation to prevent hazards.

 

Step6 - Install a cable entry gland

For running cables through your RV roof and into the walls, drilling a hole is often necessary. Use a cable entry gland—a device that seals and secures cables as they pass through surfaces like the RV roof. It prevents water, dust, and contaminants from entering the RV while maintaining a neat appearance. Choose a gland size matching your cable diameter and follow installation instructions for a watertight seal.

 

Step7 - Pulling cables through the gland

Ensure you mark the positive output of the branch connector with red electrical tape and add an inline fuse downstream to protect the wire. Mark the end of the positive wire with red tape before passing both wires through the cable entry gland on the roof. Once inside the RV, connect the solar panel to the solar charge controller.

 

This is the comprehensive guide for mounting solar panels on your RV roof. It gathers practical insights from seasoned RV owners to streamline access to effective installation methods. Before commencing any project or making substantial purchases, we recommend thorough research and consultation with professionals. We DISCLAIM any liability for damages to your RV or injuries arising from the application of our tips, advice, or instructions.