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Kulp's of Stratford engineers and installs building integrated photo voltaic systems, sometimes referred to as BIPV. The emphasis here is on two areas or concern; the systems are engineered and the systems are integrated into your building.

System Engineering

Engineering a solar electric solution involves many aspects; professional site assessment, electrical design, material choices, financial return on investment calculation, regulatory filings and compliance, and by far not the least important, mechanical engineering.

Marathon Solar Roofing Systems begin their life with a computer aided site assessment. Using the industry's best-in-class Solmetric SunEye tool, Kulp's of Stratford's staff gather the most important technical data about your location and can quickly tell you whether solar makes sense for your property.

 

 

Using the data collected at your site, Kulp's solar specialist creates a National Electrical Code compliant design and prepares a financial return on investment report for your review along with a Focus on Energy Cash Back Reward application. (for sales in Wisconsin, you are under no obligation to proceed if Focus on Energy does not approve your application) Your sales person will them provide you with a detailed proposal for your consideration.

Mechanical Engineering

Kulp's of Stratford's Marathon Solar Roofing solution is superior to other photo voltaic roofing systems because it is engineered to work on your roof. Competing ideas fail to take into consideration two vitally important factors; the desirability of not making holes in the roof to secure the PV panels and a detailed understanding of how roofing systems are attached to buildings and how this impacts good engineering practices.

Some installers use brackets that require penetrations (holes) made through the roofing material to secure the solar electric panels to the roof. This practice leads to in two potential problems; the attachments only grab the plywood sheeting which isn't strong enough to hold the loads cause by wind lifting the panels, and, the likelihood of future leaks is high.

 

 

Another method attempts to mount the PV panels to the standing seams of the roof using a commercially available bracket called a S5 clamp.

 

 

The problem with this approach is that it ignores how standing seam metal roofs work.

Standing seam metal roofing systems are designed to expand and contract as they warm and cool. A properly designed and installed standing seam metal roof takes this into account. The best practice is to attach, pin, the metal sections at the ridge of the roof and allow them to float over a cleat at the eave. Additional clips are place under the seams that are designed to allow the sections to slip. In this way the metal can experience its normal expansion and contraction while all of the attachment points are under the metal and out of the elements. The final product is a durable roofing system that is watertight.

Placing PV panels on top of the standing seams, while doable from an installation perspective, interferes with the prober working of the roofing system. The aluminum frames of this type of PV panel, often referred to as crystalline panels, expand and contract at different rates than the metal roofing they're sitting on. This difference in rates, known as the displacement delta, will cause the S5 clamps to rock back and forth and cause the metal roofing panels to bow upward. Since the S5 clamp is held in place by a simple set-screw this rocking motion will eventually loosen their grip on the seam. And as they are covered by the PV panels there is no way to inspect or tighten them without removing the entire PV system from the roof.

Of equal concern is wind uplift. Crystalline PV panels are flat on top and hollow underneath. This produces a lifting surface (think wing). As wind blows over or past the panels they exert and upward force on their mounting system. Standing seam metal roofs, like most any other roofing system, are designed to be pushed down on. Rain, snow, and wind press downward on the roof surface. This is what the roof system, and the structure underneath it, are designed to withstand. Only specially engineered roofing systems - read very expensive - are intended to withstand uplift.

So placing crystalline PV panels on standing seam metal roofs is a poorly thought out solution. Doing so leads to much higher likelyhood of a roofing system failure.

So what is a well thought out, properly engineered, solution?

BIPV, building integrated photo voltaics allow the roof to be the PV panel.

The beauty of this approach is clear - all of the engineering concerns are properly addressed AND the final result is something that looks like it is part of the building rather than looking like something that was slapped on the building.

Their way -

 

Kulp's way -

 

Kulp's BIPV solution will produce more usable power on an annual basis and will cost you less to install than crystalline systems. Kulp's BIPV systems are engineered solution, not make-do. Kulp's BIPV systems are engineered and installed by solar and roofing professionals to last a minimum of 25 years.

read more about how it works

800.285.2917

solar@kulpsolar.com