Facade rendered: what can still be judged on the finished build-up

By Peter Wey and Dominik GrolimundLast reviewed August 10, 2026

The finished facade shows the result, not the build-up. Surface, connections and details can be judged. Whatever lies underneath can only be clarified through photos from the construction phase.

The most common expensive defects in the finished facade

Cracks above window and door corners

Diagonal cracks at the corners of openings point to weak spots in the substrate. The exact cause can usually only be clarified with photos from the construction phase.

Visible board joints in raking light

If the outlines of the insulation boards show through, it is often a visual defect. Whether there is an execution error can only be clarified in retrospect through photos of the unrendered facade.

Poor plinth detailing

Too little distance to the ground (guideline: under 30 cm) and a missing splash protection lead to moisture. In the long term, this causes algae or damage in the plinth area.

Missing or leaking connection joints

At windows, railings and canopies, the joints must be sealed permanently flexible. If these are missing or leaking, water can penetrate behind the render.

What you should document and check now on the finished facade

Photograph each facade side in raking light
Photograph each side in the morning or evening with a flat angle of light. Unevenness and visible joints stand out most clearly then.
Zoom into opening corners and connection joints
Capture window and door corners individually to spot cracks early. Photograph the connection joints on frames and railings in the same pass.
Check plinth and transition to the ground
Photograph the bottom edge all the way around in detail. Make sure that the distance from the render to the ground is clearly visible on the pictures.
Request photos of the insulation layer
Ask in writing for photos of the facade before rendering. Important are pictures of the insulation board joints, the fixings, the opening corners and the plinth.