We receive calls every day about façades, façade materials and our experience with certain façade solutions. We made a short list of FAQ ’s and want to share with you six common ‘misunderstandings’ about façade construction. 

1. Corten steel stops shedding rusty water after three years

False! Even after 40 years, a façade made with untreated Corten (weathering) steel sheds steel particles in/during a rain shower. We have proven this experimentally. Always take the flow of (rain-) water along the façade into account when designing a Corten steel skin for a building. Avoid contact with other materials and use a gravel bed at ground level.

2. It is possible to use untreated aluminium in a façade

True. In the Dutch climate that is possible. It does not happen often: weather conditions (rain, wind) and use(-rs) leave traces on an untreated surface that are hard to erase/clean. The reason to use a finish on aluminium is mainly aesthetic. The oxidation process of untreated aluminium is relatively slow: the structural capacity of the untreated material is consistent for a (very) long period.

3. Anodized aluminium is prohibited in the Amsterdam area

False! The Amsterdam region has strict regulations where façade materials are considered, but there are anodization methods that meet the requirements. Like with coatings, there are different qualities in anodizing. Make sure that the quality fits the requirements. If you have any doubts about using anodized aluminium in Amsterdam, ask our engineers!

4. Living green façades tend to rust

False! Unless Corten steel has been used and oxidation is desired. But even then, the greenery will hardly have any influence on the degree of corrosion. With the current quality of powder coatings and anodization, using plants on steel or aluminium facades does not have any influence on the durability of the façade. We do recommend refraining from using self-adhesive plants, but only for reasons of maintenance.

5. Anodized aluminium has a tendency to flake

No, it has not. Anodizing is an electrochemical process that modifies the top layer of the aluminium into a durable layer of oxide. There is no added extra layer or material, like with coating. The top layer of the aluminium becomes porous during the anodization process and that allows adding colour. The colour is ‘anchored’ within the material.

6. It is possible to make facades with 100% recycled aluminium

Yes and no. Technically it is possible. But it does not happen on a larger scale and is therefore more expensive. There is not enough ‘recyclable’ aluminium (in Europe) for the façade industry and that compromises the price of fully recycled aluminium. The good news: recycling aluminium is an easy and energy-efficient process. For aluminium extrusion profiles (like with MD Lamel) the percentage of recycled aluminium is growing steadily. We hope that other product groups will follow. This is something we want to work on, with our clients and suppliers.