Housing complex renovation, Austria

The famous Austrian architect Viktor Hufnagel built the housing complex in the 1980s. The prestigious property comprises 380 residential units and has around 50 stairwells.

From 2020, all 3,600 windows in the housing complex were replaced step by step. The particular challenge here: damage to the interior reveal had to be avoided to the greatest extent possible. Each window had to be installed within one day so that the residents didn't have to move out during the renovations.

The inside of the window soffit was finished in plaster. After airtight connection with Fentrim® IS 20, this was concealed with plaster. On the outside, the visible driving rain resistant connection was established using the high-performance SIGA Meltell® hybrid sealant.

Particularly for window installation in the renovation area, it was important for Felbermayer Fenster GmbH to have a connection which is easy to handle and is permanently airtight and resistant to driving rain. For Josef Kollarich, Site Manager at Felbermayer Fenster und Türen Erzeugungs GmbH it is clear:

“We have found a brilliant sealant in SIGA Meltell which meets our high standards for handling and quality, as well as usability for various joint widths in renovation.”

He also explains why Felbermayer Fenster und Türen Erzeugungs GmbH decided on a collaboration with SIGA:

“The advice and support in the preliminary planning of the renovation connection and selection of the right SIGA materials was a fundamental part of the decision to use SIGA as the supplier for the renovation connection.”

Ing. Florian Freydenschlag is an Authorised Representative at Ertl GmbH, the engineering firm for window and facade technology in Vienna. We asked him what he considers to be the key points for a window test in the field of renovation, what the particular challenges of this project were and what he sees as the benefits of the SIGA products.

What is important to you in a window test in the field of renovation, as well as in a new build?

In my opinion, the most important point in renovation, as well as in a new build, is the easiest possible handling of the products, i.e. the fitters must be able to introduce and apply them without a significant amount of additional effort. In my opinion, this is so important because the installation quality is improved as a result and no components can be forgotten.

What are the technical challenges?

The technical challenges in the field of sealing can clearly be found in the field of permanent bonding and the substrates found on site.

What stands out for you about using SIGA products for a window-masonry connection?

The main thing that stands out for me is the adhesive strength, because it is practically impossible to remove the film again once it has been applied to the masonry or element. During the course of construction, this has the advantage of course that hardly any improvement work is required.
 

How did you find the collaboration with SIGA's technical support department?

The support was and is unique. To date, all enquiries (e.g. regarding product specifications) or similar have been answered or clarified immediately.
 

Where are the weak points in these connections most often found?

I notice most weak points in conjunction with the bond to the masonry. This very frequently results in detachments which require time-consuming repairs. Products which require additional products (e.g. seam paste) in order to ensure a clean connection are also often used. This often results in defects in the property because the additional products are easily forgotten.