From combustible to covered: how Tennis Club Tanthof secured solar panels on a bitumen roof

The dilemma: uninsurable solar on a bitumen roof

Tennisvereniging Tanthof in Delft had big sustainability plans: cover the 200 m² clubhouse roof with solar panels to cut energy costs. One major obstacle stood in the way – the roof was a traditional bitumen roof, which is highly combustible. Their insurer flatly refused coverage for solar panels on such a roof, citing the elevated fire risk.

Tanthof’s situation was common: bitumen roofs and EPS insulation are prevalent on older buildings, and insurers have increasingly strict fire safety demands for adding PV systems. Essentially, without changes, Tanthof’s solar dream was dead in the water due to the roof’s fire profile.

The solution: AllShield Blue non-combustible coating

Enter AllShield Coatings. Tanthof discovered our mineral roof coating as a potential fix to make their roof fire-safe and insurable. In a straightforward application, AllShield Blue was spray-applied directly onto the existing bitumen – no need to remove the old roofing. Once cured, this coating formed a 3 mm thick A1-rated protective layer.

In effect, Tanthof’s roof went “from combustible to non-combustible” in one step. This drastically lowered the fire hazard: any flames (from a short-circuit, for example) would not spread across the roof or ignite the underlying materials.

Critically, AllShield Blue meets the NEN 6063:2019 standard for external fire safety of roofs (resistance to flying firebrands) and achieved an A1 rating in fire tests. These credentials helped convince the insurer. The coating addressed their concerns by eliminating the roof as a fuel source for fire.

It’s a solution aligned with expert risk guidance: avoid PV on combustible roofs, or add a proper thermal barrier if you do. In Tanthof’s case, the AllShield coating became that thermal fire barrier, making the roof equivalent to a non-combustible construction in the eyes of underwriters.

Bonus benefits: durability and performance

Beyond fire safety, the club gained other benefits. The AllShield coating creates a seamless, weather-resistant top layer that extends the roof’s life by shielding it from UV and weathering. In Tanthof’s case, this means their roof will last many more years, outliving the solar panels themselves – which is ideal, since no one wants to dismantle a PV array just to re-roof.

The coating’s white variant was used, giving the roof a reflective surface that helps keep the building cooler in summer. This improves indoor comfort for the clubhouse and can slightly boost solar panel efficiency due to a cooler roof environment.

Moreover, the application was quick and cost-effective. Since we did not need to strip off the old bitumen, there was minimal disruption and no large waste disposal. The process was eco-friendly and budget-conscious – an important factor for a non-profit sports club.

The result: a sustainable & safe outcome

Thanks to the partnership between Tanthof and AllShield Coatings, the club can now proceed to install its solar panels with full insurance coverage. What seemed like a showstopper issue was resolved – the insurer reviewed the AllShield documentation and agreed to insure the system, given the roof’s new fire-safe status.

It’s truly a win-win situation: Tanthof gets to generate clean solar energy and reduce electricity bills, while simultaneously upgrading the safety and longevity of their facility’s roof.

This case highlights an inspiring narrative: a small community club taking initiative to become sustainable, and overcoming modern challenges with modern solutions. Tanthof’s experience can serve as a model for many other organizations sitting on the fence of solar adoption due to roof fire concerns. With AllShield Blue, “uninsurable” roofs can be made insurable. Combustible surfaces can be made non-combustible without expensive rebuilds.

In the end, Tanthof members can enjoy their tennis knowing the club has a future-proof, safe roof over their heads and a new solar array powering the lights. It’s a story of practical innovation – turning a flammable problem into a fire-safe solution – allowing green energy and risk management to go hand in hand.

AllShield gave us 3-in-1: Free energy, cooler clubhouse and bitumen life extended!