What Are PV Mats And When Should You Use Them?

In a recent article last week, on our website, we took a look at a type of photovoltaic solar panel which does not necessarily require damage to the roof for mounting an attachment.   Together with that article, this week’s article below is part two in a series. The outline of this second article follows:

The advantages of PV mats

In last week’s article, we looked at several different advantages of the flexible mat alternative to traditional hard solar panels.  

Flexible flat roof solar photovoltaic mats offer a compelling alternative to traditional rigid rooftop panels. Their lightweight and adaptable design allows for easy, non-intrusive installation directly onto flat roofs. Unlike conventional panels that require drilling and mounting hardware, flexible mats eliminate roof penetrations, preserving roof integrity. Their modular nature accommodates roof contours and transitions, while reduced wind uplift potential enhances durability. Compatible with various flat roof types, these mats optimize space, reduce load, and lower environmental impact. Although slightly less energy-efficient, they efficiently utilize roof space and contribute to overall energy generation.

The biggest advantage, though, of almost thelose listed, from our company’s perspective, is that the solar mats do not require bolting through the parapet. Technically, mounting of traditional hard or rigid solar panels also does not require bolting through the rooftop membrane, But in Washington DC over 90% of the solar panel installations we see most often are bolted through the aluminum coping at the side demising walls of rowhomes.  

Dangers of traditional hard PV panels

The building code in Washington, DC puts the responsibility on the installer of the panels to verify they are installing their panels in compliance with the aluminum coping manufacturer and the roofing manufacturer installation instructions.  Our building code and the International Building Code (IBC) may seem a bit backwards in this particular area, and even though the word ‘International” is in the particular building codes name, it’s not an internationally required code.  Even though the name ostensibly implies the IBC is a (Authority Having Jurisdiction (AHJ), the IBC actually has no authority.   Instead local municipalities, in the USA and abroad, can choose to adopt the IBC regulations, wholesale, or in part as they choose, item by item.

The vast majority of roof manufacturers and coping manufacturers require that the coping metals have no fasteners installed in the coping at areas where the coping is in a near horizontal position.   As well, the building code in DC allows penetrations through horizontal or near horizontal coping but only under specific approved details, nearly never followed by solar panel installers in Washington, DC.  As a result, time and time again, we are called to fix leakage into parapets, through coping, at the mounting locations of traditional PV solar panels.

Shortcomings of flexible mat PV panels

The flexible mats save the need for such penetrations or fastening through the horizontal roof membrane or through copings; however, there are some considerations to keep in mind if or when using flexible solar panels:

• Efficiency: As mentioned earlier, the efficiency of flexible solar panels might be slightly lower than that of traditional rigid panels, so it’s beneficial to choose high-quality panels with decent efficiency ratings.
• Maintenance: Regular inspection and maintenance are necessary to ensure the long-term performance of the solar panels and the integrity of the roof beneath.
• Roof Compatibility: Ensure that the roofing material is compatible with the adhesive or mounting method used for the flexible solar panels to avoid any potential damage or warranty issues.

Overall, flexible flat roof solar panels can be an excellent option for flat roofs where traditional mounting methods are impractical or unwanted. They offer a more adaptable and non-intrusive solution for harnessing solar energy. However, it’s essential to work with a reputable solar installer who has experience with flexible solar panels and flat roof systems to ensure a successful and long-lasting installation.

Smart proactive replacement, construction, upkeep and maintenance of low slope roof and mansard roof systems requires an enthusiastic interest and understanding of historical methodologies, waterproofing principles, and building science.   Here in Washington DC, historic and modern residential and commercial buildings are extremely expensive and the roof and related systems provide the shield that preserves the building. 

We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the value of quality construction and building maintenance, and develop a relationship with our company.  You can learn a lot more on our blog.  Feel free to check it out.  If you have questions about the roof and related systems of your building in Washington DC, contact us or fill out the webform below and drop us a line.  We will be in touch if we can help.