ᐅ New Build Exterior Facade: Brickwork / Render

Hello, we are currently in the planning phase for the construction of a detached single-family house in Owl. Now the question inevitably arises whether the exterior facade should be finished with a single-layer render with an external thermal insulation composite system (ETICS) or a two-layer facade with Dutch-style facing bricks. Our target is a KfW 70 energy standard. We had basically decided on bricks because they allow better breathability and I have not been particularly impressed with tightly sealed render facades so far, especially regarding maintenance. However, a builder recently told me that there are render facades that can last 30 years with the first coat of paint. Combined with an air-to-water heat pump and integrated mechanical ventilation, this would be acceptable. Additionally, the cost for a render facade is about 10,000 to 15,000 euros less than for a brick facade.

So, my question is: which ETICS setup is the most durable, not only considering the insulation material but also the render and paint? That also plays a significant role.

Thanks in advance for your answers....

derstefanm schrieb:
. We had basically already decided on brickwork because it "breathes" much better, and so far I have not been very impressed by sealed rendered facades, especially regarding maintenance.

Since when do bricks breathe?

Hello,

derstefanm schrieb:

We had basically already decided on brick veneer because it "breathes" much better.

Interesting statement

derstefanm schrieb:

But a contractor recently told me that there are plaster facades which can last 30 years with the first coat of paint.

These statements have been around for a long time; however, I don’t consider them very reliable. You can increase durability with a fungicidal-algicidal coating; these coatings are also available in eco-friendly versions. When calculating cost-effectiveness, you should always compare the costs of brick cladding with the expected repainting intervals of a plaster facade; construction method does not belong in this comparison.

From our experience, the degree of soiling and cleaning possibilities depend significantly on the house’s orientation on the lot and the number of floors. For example, if the weather-exposed side faces north and the garage is located there as well, and it is a typical single-story building, regular cleaning of the north façade with a pressure washer is usually sufficient. This is easy for a homeowner to manage, even for someone not very handy.

It is different if the building—which I don’t really see for OWL—is located in a coal or industrial area. In such cases, a brick veneer won’t help much either; it just creates the illusion of a "clean" façade. Because even brick absorbs rainwater, then dries, trapping dirt inside. That’s why especially white brick facades often look "dirty" after a short time.

Regards, Bauexperte

By "breathing," I mean that a cavity wall construction combined with clinker brick is more vapor permeable and can transport moisture more effectively.

What about the insulation material; are there differences in terms of durability? Is the coating the only crucial factor?

You can ignore moisture diffusion through the walls. Not even 1% of the moisture generated inside the house diffuses out through the walls. Whether it’s 0.3% with brick veneer or just 0.2% with external thermal insulation composite systems (ETICS) makes hardly any difference. Moisture only leaves the house through drainage and ventilation!

What also comes to mind is a bicycle falling over in an unfortunate way and causing a hole in the render. This would most likely be completely impossible with brickwork.