Sustainability

Knauf Insulation’s pioneering pilot aims to unlock secrets of upscaling quality renovation

By Knauf Insulation
March 15, 2022

Knauf Insulation has joined a pioneering European Union project to explore new ways to upscale the deep renovation of single-family homes.

The DRIVE 0 concept, part of the EU’s €80 billion Horizon 2020 innovative initiative, is an incubator for fresh ideas, methodologies and research designed to energise deep renovation across Europe with a focus on improving energy efficiency, reducing carbon, driving the circular economy and improving living conditions.

Domen Ivansek Head of Building Science

Knauf Insulation’s Head of Building Science, Domen Ivanšek, says: “Buildings are responsible for consuming 40% of Europe’s energy, emitting 36% of its greenhouse emissions, using 50% of all extracted material in Europe and generating 35% of its waste.”

Renovating Europe’s buildings to make them more energy efficient would cut that carbon, unfortunately only 1% of Europe’s building stock is renovated every year.

That is why DRIVE 0 is focusing research on finding new ways to upscale the renovation process and drive greater awareness of material reuse and recycling. Under the programme, seven countries, including a project in Slovenia managed by Domen, were selected to look at solutions to make mass renovation more effective in line with specific building challenges in different climate zones.

These included projects to renovate semi-detached homes in Ireland, terrace houses in the Netherlands, windowless ‘blind walls’ in Spain, an old manor in Italy, a multi-apartment block in Estonia, apartments in Greece and the single-family houses in Slovenia.

 

Improving the quality of renovation

Domen, who oversees the Slovenian projects, says: “A total of 89% of the 524,000 residential buildings in Slovenia are single-family houses of which 95% were constructed in the 20th and 19th centuries”.

These homes have large interior spaces that are expensive to heat, have a sizable carbon footprint and are usually badly insulated leading to poor thermal comfort and problems such as mould. Renovation is widespread in Slovenia, but it is often only partial and unfortunately the quality is not always the best.

“In our DRIVE 0 project we are focusing on deep renovation to address issues holistically — introducing measures to improve energy savings and indoor environmental quality (IEQ),” says Domen.

House During Deep Renovation Slovenia

“The project also examines aspects of sustainability such as the impact of retrofit work on tenants and the environment, reducing the carbon footprint of buildings and raising awareness of the importance of circularity in renovation.

“In addition, there are a lot of similar buildings in neighbouring countries, so we want to explore renovation processes that can be replicated across Europe.”

 

So, what does the Knauf Insulation project involve in Slovenia?

Slovenian House Renovation Thermal Cameras Inspection

The company selected three representative single-family houses, then carried out preliminary building inspections using thermal cameras, taking sound insulation measurements, installing remote sensors for indoor air quality, taking geometry measurements and assessing energy and water bills.

Structured ‘anthropological’ interviews were also carried out with the occupants to understand their pain-points and reasons for the retrofit as well as gain subjective insight into their wellbeing, living comfort and thoughts about material circularity.

Theoretical energy savings

Today, one of the buildings has been completely renovated, work on the second has started and the third is waiting for the go-ahead for renovation work. The initiative is scheduled to end in 2023 to enable a reliable ‘before and after’ renovation comparison of winter and summer data, as well as follow-up interviews with the building occupants and detailed building and material reports.

“It is still too early to talk about results,” says Domen. “But we have theoretically modelled various scenarios for a noticeable reduction in energy demand and carbon footprint.

“However, these are only calculations based on assumptions, real performance based on actual factors, including non-perfect quality of works, lower actual efficiencies of devices and changing user habits, is what counts in the end. We have to wait to get enough data after the renovation to assess the real savings.”

The first finished deep renovation included installing triple-glazing, new doors and walls featuring an external ETICS façade incorporating 16cm of Knauf Insulation Rock Mineral Wool. The pitched roof and loft areas were then filled with SUPAFIL® Timber Frame Blowing Wool.

The ceiling of the cellar was insulated with non-flammable Rock Mineral Wool lamellas, two VELUX® Sun tunnels were added in the hallway, all light bulbs were replaced with LEDs and nine ventilation devices with heat recuperation were installed. Finally, the old bio-mass central heating system was replaced with a heat pump.

Slovenian House Renovation Pitch Roof Isolated Supafil Blowing Wool

The ceiling of the cellar was insulated with non-flammable Rock Mineral Wool lamellas, two VELUX® Sun tunnels were added in the hallway, all light bulbs were replaced with LEDs and nine ventilation devices with heat recuperation were installed. Finally, the old bio-mass central heating system was replaced with a heat pump.

 

Circularity awareness in renovation works

An important aspect of the project has been circularity — not landfilling used building materials but, for example, recycling or reusing them.

“There are challenges,” says Domen. “We know our Mineral Wool can be 100% recycled, but often it is hard to separate building elements for reuse after 50 years, such as ETICS facades which are highly predominant in Slovenian family houses, used in new builds and renovations. However, we are experimenting to find alternative more circular solutions.

“For example, a ventilated façade will be installed on one of the walls using the Knauf Insulation Diagonal 2H ventilated system which can be completely disassembled into primary elements. These elements can then be further processed and ideally returned to the material loop.

Glass Windows Recycled For Circular Economy

“Also glass from old windows was separated and delivered to an official recycling facility along with old Mineral Wool from the roof and off-cuts. Meanwhile, much of the waste wood from cladding and window frames was used for heating material in another holiday house.”

Inspiring better renovation

“I am confident the data and research generated from the Slovenian renovations and the other six DRIVE 0 demo cases around Europe will prove to be very valuable,” says Domen.

“At Knauf Insulation our hope is that it will help to inspire better renovation processes and better buildings by focusing on building users, shrinking the carbon footprint of buildings, reducing energy and costs and driving the circular economy.”

 

• To read more about the Slovenian project visit the DRIVE 0 case story pages here.