Part 3 of Our Solar Photovoltaic Series
Solar companies require rooftop real estate for their Solar PV (photovoltaic) arrays, making your flat commercial or industrial rooftop in Toronto a valuable asset. If you are a landlord with solar assets on your industrial rooftop or are considering doing so, this article on maintaining your roof when you have a solar PV system is for you.
This is Part 3 of our Solar PV series. If you are interested in this topic, we invite you to read Part 1 (Basics of Solar PV) and Part 2 (Installing Solar PV on Your Roof).
Maintenance Issues with an Industrial Rooftop Solar PV System
Leasing your rooftop to a solar outfit can bring in revenue. At the same time, you may not be aware of the specific attention needed when a solar array sits atop the roof of your commercial or industrial property. We’ll get into more detail below, but the main point is that solar arrays can create or increase certain risks to the health and longevity of the roof’s membrane. This makes it more essential than ever to schedule regular inspections and keep with ongoing roof maintenance.
Whether you have leased your roof for solar or are considering doing so, it pays to educate yourself on potential negative outcomes–and learn how to reduce risk.
Keep the items below in mind when working with your roofing company and solar PV outfit.
10 Essential Points for Maintaining an Industrial Rooftop that Has a Solar PV System
1. Schedule Regular Annual Roof Inspections
Toronto’s tough climate—with cold, thaws, high winds, and storms—is rough on roofs and can cause damage. A solar array further increases the risk of roof damage. Annual inspections of your industrial or commercial roof can keep the maintenance costs in check in the long term.
2. Keep Up with Ongoing Maintenance
As with maintenance of every type of roof, it’s best to catch problems when (or even before) they occur. The better the roof’s condition, the less frequently it will require extensive (and costly) repairs, extending its life and deferring the capital cost of replacement. That said, a solar PV system makes it much more difficult for technicians to access the roof for essential maintenance.
Keeping up with repairs also becomes a bit more complex as the roofing and solar contractors must coordinate and take the time to remove and reinstall the solar PV panels, racking, electrical cabling, combiner boxes, and any other gear in whole or in part. As you would expect, adding solar PV tends to add to the time and cost of maintenance and repair. Plus, there is an impairment in revenue while the panels are disconnected.
Even though maintenance with solar PV can be complex, it doesn’t pay to put it off—quite the opposite.
3. Safe Access to the Roof
Repairing leaks and performing other roofing work, requires ready–and safe–access to the roof. Take precautions to protect workers. For example, electrical wiring should be neat and tidy to avoid creating a tripping hazard for tradespeople when they access the roof for inspections, repairs and maintenance.
4. Overhanging Trees
There are several reasons why overhanging tree limbs must be removed. Limbs that break off during a storm can cause damage to the roof and the PV array. Tree limbs can also rub against the membrane, causing cracking, splitting, or holes that lead to leaks. In addition, fallen leaves can block drains, scuppers and/or eavestroughs, and trigger potential leaks.
5. Debris and Vegetation on Your Industrial Roof
Organic debris, such as leaves and nesting material, can get trapped under the solar panels and racking, potentially blocking the drainage system. If a roof inspection reveals an obstacle to drainage, any debris should be cleared as quickly as possible.
6. Coordination Between Parties
The roofing and solar companies must work together during installation and when maintenance is needed. A meeting before the system “goes live” can hammer out respective roles and responsibilities to avoid unnecessary damage and disagreements down the road. Important issues include who will bear the cost of work, scheduling, and logistics if the roof needs to be repaired or replaced. Such matters are crucial if the PV array needs to be removed for the roofing work and then reinstalled afterward.
7. Compressible Insulation and Substrate Deflection
Ponding water that stretches or deforms the membrane is a common cause of roof damage, leaks, and, worst case, roof collapse. Solar PV arrays and their heavy ballast can be a particular risk with compressible insulation, requiring additional maintenance to avoid leaks. As always, inspections and ongoing maintenance should be a priority.
The extra weight of PV ballast materials can overtax the membrane and the roof structure, causing it to bow down. The resulting dips, or deflection, in the roof assembly are a perfect place for water to pond. The risk is even higher if the array’s placement causes unequal weight distribution. If an inspection shows deflection, the roofer may recommend drainage options to decrease ponding or other solutions to build up/support the roof assembly.
8. Wear and Tear on the Roof Membrane
High winds and other situations can cause the PV’s racking system to move, increasing wear and tear on the roof. Problems can occur even when following the PV manufacturer’s specifications. Regular roof maintenance helps ensure the integrity of the membrane, as does having the solar company adjust the supports under the racking system on an as needed basis, including after a major weather event, to keep them in their proper position.
9. Wind Damage
How do you know if installing a ballasted PV system is feasible? Wind loading is one critical factor. Ballast that is too heavy or improperly placed may damage the membrane. High wind areas require more ballast or hard anchor points to anchor the array securely. In a high-wind location, the PV installer can protect against roof damage by installing the array in the correct location. After a major wind storm, the landlord should call the roofer for an inspection and have the PV contractor check that the racking is anchored securely.
10. Overburden Waiver
A roof warranty often requires an overburden waiver, including an agreement that the PV system will be removed if the roofing company needs access to the roof for capital repairs. Landlords should maintain these warranties because of the costs associated with removing and reinstalling the solar array, related racking, and electrical components. The warranty may also cover leaks or damage to the membrane should it occur.
Specialty Roofing Systems: Does Your Overburden Policy Hold Up?
Example of Overburden Waiver: Johns Mansville Photovoltaic Overburden Additions on JM Guaranteed Roof System
Maintain Your Roof – With or Without Solar PV
The bottom line is that regular inspections and ongoing maintenance will extend the life of any rooftop, whether or not it has a rooftop solar PV array. Before contracting your rooftop to a solar PV company, consider all the pros and cons, the costs, and the maintenance required to protect and extend the life of your roof.
Are you thinking of contracting your roof for solar PV, or do you currently have a solar PV array? Before hiring a roofer, ask if they have previously inspected and maintained a roof with a PV array. Elite Roofing has the experience you need in the greater Toronto area. Talk to us about how we can expertly maintain your roof when you have a solar PV array. Call us today.