The impact of a fire can affect many – families, businesses and the community. In 2016, pharmacist Klaus Dewies faced his worst nightmare when a fire broke out in the building that hosted his business and his home. His family had maintained the historic building in the old German town of Haltern am See since 1919. The pharmacy, where Dewies worked, was located on the ground floor and the top floor was converted into a bright apartment for his family. To add to the tragedy, the building itself is protected and considered to be one of the most beautiful facades in Haltern.

The challenge

Luckily, visitors at the neighbouring ice-cream parlour noticed black smoke, so everyone in the building was evacuated quickly and safely. They assembled outside and watched helplessly as the local fire fighters tried to control the fire – and as flames, smoke and around 6,000 litres of water almost destroyed the building. The water alone used to quench the fire could fill six standard car trailers! By the time the fire was extinguished, the roof and interior were completely destroyed.

The investigation carried out by the fire department in the aftermath showed that the trigger occurred during work on the historical facade when a painter tried to remove acrylic resin paint using a Bunsen burner. The existing roof insulation ignited as a result. For Dewies, fire safety became a top priority when considering the resulting renovation of the historic roof and creation of a new roof structure.

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Frankfurt am Main, Germany

Project location

Hirsch pharmacy
Frankfurt am Main


The solution

Carsten Schade and his team were hired to take care
of the renovation and rebuild project, and they were in
for a surprise when they removed the damaged parts
of the old roof structure – there were actually two
roof trusses!

“You rarely find a beam construction like this,” explains
Schade. “An external beam structure with a roof overhang
covered the historic beams where they connected
with the outer wall. This was to protect them from moisture.
In principle, it was a good idea. But in the event of
a fire, the fire and smoke could initially go unnoticed in
the cavity between the two roof trusses.”

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Pitched roof insulation

Effective pitched roof insulation is ideal for residential and commercial properties, offering additional thermal comfort, sound protection and exceptional fire resistance.

The pitched roof or attic area of a building can be insulated in many ways. ROCKWOOL offers exciting products for newbuild properties as well as renovations.

Made from premium-quality stone wool, there are ROCKWOOL products available for pitched roof insulation below, between and over rafters, as well as insulation that is placed in the loft level.

"I have chosen the new insulation very consciously. It’s a good feeling that the historical wooden beams – and of course we – are protected by non-combustible insulation.”

Klaus Dewies

pharmacy owner

Stone wool – naturally fire resistant

Insulating a roof is an effective way to minimise heat loss and reduce heating bills and is important to consider as a major aspect of any roof renovation project. Non-combustible stone wool was the obvious insulation
choice for Dewies. Supported by Schade and his team, they decided on a ROCKWOOL insulation solution for pitched roofs that offered heat, noise and – most importantly – fire protection.

The geometry of the roof was a challenge when it came to installing the modern insulation, as the large dormer windows at the front and back created many ridges and throats. This made a lot of detailed work necessary, requiring insulation and foils to be carefully cut and worked on. Here, the fact that the ROCKWOOL stone wool is easy to cut and prepare proved to be a substantial benefit, which helped the team complete their
intricate work while avoiding errors.

The extensive renovation also needed to meet the requirements of the Energy Saving Ordinance 2016 (EnEv). But this was not a concern for Schade and his team. They could complete the renovation with peace of mind knowing that the ROCKWOOL insulation system was developed in accordance with these requirements.

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Energy Saving Ordinance (EnEV)

The Energy Saving Ordinance – or Energieeinspaarverordnung (EnEV) as it’s called in German – is an important part of the energy and climate guidelines issued by the government in Germany. First released in 2002, it was reissued and amended several times, with the latest coming into force on January 1, 2016.

The EnEV poses energy requirements for new buildings, taking the structural heat insulation of the building as well as the energy efficiency of the systems used – heating, ventilation, cooling, light – into account.

Project Data

Year 2018
Building Type

Historic single family home with pharmacy

Application Roof insulation
Product type Masterrock