The applicator applies Fixit 222 Aerogel high-performance insulating plaster directly onto the existing façade and integrates it to increase the insulation value.

Energy-efficient renovation directly on the old plaster with Fixit 222 Aerogel

Project process

Solution approach

Execution

Result

Orange plastered exterior façade renovated with Fixit 222 Aerogel high-performance insulating plaster

Heating requirement halved thanks to Fixit 222 Aerogel and new windows

Even older and previously poorly insulated buildings can be successfully made fit for the future. One example of this is the completed energy-efficient renovation of a detached house in St. Gallen. The building from 1946 showed the weaknesses typical of its age: insufficient thermal insulation and therefore high heating energy consumption. 

The energy-efficient renovation has almost halved the heating requirement for this building thanks to the Fixit 222 Aerogel high-performance insulating plaster and the simultaneous installation of new windows. Converting the central heating system to a heat pump is likely to reduce energy requirements even further.

Project schedule for energy-efficient building renovation with Fixit 222 Aerogel and other measures

In a first step, the basement floors of this building were insulated and the roof was completely rebuilt and fully insulated. In the second step, the exterior walls and windows were tackled as weak points in the project. 

Deciding on the right insulation solution was no easy task, as the visual requirements of the building envelope and appearance also had to be met. The originally planned insulation solution consisted of a conventional system with mineral wool insulation boards, however, during the detailed planning, it quickly became apparent that the required insulation thickness would lead to aesthetic problems. The window reveals would have been transformed into niches up to 40 cm deep, which would have had disadvantages in terms of light incidence on the one hand, and the installation of shutters on the other.

What can be done to achieve the required or desired insulation values without compromising the appearance of the building?

This question arises time and again in the case of energy-efficient renovations, as the required insulation thicknesses can greatly distort the proportions of the building. Renovations with thick thermal insulation panels are therefore out of the question for listed buildings. Even with normal buildings that simply characterise the neighbourhood or street, excessively thick insulation is a nuisance. The solution is a holistic renovation strategy, as this takes into account both energy-related and aesthetic aspects. Another option is to use a better insulating material that is thinner and therefore less visually restrictive.

Detached house with aged façade and no insulation before renovation with Fixit 222 Aerogel
The house to be renovated is covered in scaffolding and protected from sunlight and wind

Fixit 222 Aerogel as an innovative product solution for thermal insulation with aesthetic appeal

With Fixit 222 Aerogel high-performance insulating plaster, even aesthetically demanding façades can be greatly improved in terms of energy efficiency without the insulation measures being obviously visible. Jörg Drechsler has been recommending the use of high-performance insulating plaster for many years if no conventional solution can be used for visual or monument protection reasons. He therefore decided to use the innovative Fixit 222 Aerogel solution for his own house as well.

By using the high-performance insulating plaster, the depth of the window reveals could be kept to an acceptable level despite the complete insulation. In this project, it was even possible to dispense with the prior removal of the base plaster, as the window sills were also replaced with new elements with an insulating core.

If, on the other hand, the windows are framed by elements that are to remain visible, the base plaster must be removed to gain a few centimetres of insulation thickness – because even a few centimetres make a difference with high-performance insulating plaster!

How is Fixit 222 Aerogel high-performance insulating plaster applied?

Energy expert Jörg Drechsler commissioned the plastering company Kessler Gips AG from Herisau for the plastering work, which has been known to him for some time and which has a great deal of experience in the renovation of existing buildings. However, the company had never worked with Fixit 222 Aerogel high-performance insulating plaster before and was therefore somewhat sceptical about the product. Our application technicians and experts for Fixit 222 therefore explained the individual implementation steps and the optimum handling of the material at the start of the work.

When the work was carried out, it quickly became apparent that the original scepticism of the installers was unfounded, as the Fixit 222 Aerogel high-performance insulating plaster was very easy to work with. The product was sprayed wet-on-wet onto the existing façade by machine in two passes, each with a layer thickness of around three centimetres. The high-performance insulating plaster then behaved like a conventional plaster during the subsequent processing steps. 

In order to apply the insulating plaster in the desired and necessary layer thickness, battens have been installed on the façade as a guide.
The base area of the building is insulated using Fixit 222 aerogel.

The end result of the energy-efficient renovation: impressive energy savings!

The first two insulation measures on the roof and basement have already reduced the heating requirement to around 100 kWh per heated square metre per year. Insulating the exterior walls and installing new windows then brought the really big savings. A comparison of consumption for the years 2014 to 2020 adjusted for heating degree days with consumption for the period 2020/21 (extrapolated to one year) shows a reduction of 45 percent!

Thanks to the overall renovation concept, it is now possible to reduce the flow temperature of the heating system from 55 °C to 40 °C and a heat pump can easily generate this temperature. As soon as the heat pump is installed, energy consumption will fall massively once again: After installing the geothermal probe and replacing the gas heating with a heat pump, Jörg Drechsler calculates around 15 kWh per heated square metre per year.

 

Client: Ursula and Jörg Drechsler, St. Gallen, Switzerland
Planning: Drechsler Energy Optimisation, St. Gallen, Switzerland
Entrepreneur: Kessler Gips AG, Herisau, Switzerland

Interior with wooden flooring, staircase and historic beam structure from the Madiswil mill, and white plastered walls with internal insulation made from Fixit 222 aerogel insulating plaster.

Fixit 222 Aerogel – tried and tested

The innovative Fixit 222 Aerogel high-performance insulating plaster has been in use for more than a decade. In 2013, the quality and durability of the product was monitored and tested in parallel in a long-term test. Find out more!

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Historic apartment building with white plastered and insulated façade made of Fixit 222 Aerogel high-performance insulating plaster.

Fixit 222 Aerogel

Extremely effective insulating material, as excellent insulation values are achieved with just 4 to 6 centimetres of the light and airy insulating plaster. This makes the render perfect for the energy-efficient renovation of historic buildings.

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