A facade can be perfect in terms of material and installation, but one mistake in water drainage — and after one season, streaks, dirty marks, a wet lower section and efflorescence may appear. That is why the drip edge and flashing are not a “small detail”, but an element that protects the façade during every rain.
What Is a Drip Edge and Why Is It Needed?
A drip edge is an element or edge shape that breaks the water flow. Without it, water “sticks” to the surface and starts running down the wall, even if there is a canopy or projection.
What happens without a drip edge:
streaks on the façade
constant moisture near joints
dirty plinth
faster ageing of the finish
Flashing: Why It Must Work, Not Just “Exist”
Window flashing or flashing on projections must do one thing: direct water outward so that it does not enter the joint or flow under the finish.
Common problems caused by incorrect flashing:
water runs back toward the wall
stains appear under windows
window reveals become wet
in winter, ice accumulates and expands weak areas
5 Common Mistakes That Keep a Facade Wet for Years
1) No Slope
If the flashing is almost horizontal, water does not drain away. It stays like a “puddle” and looks for a gap.
2) No Drip Edge
When the edge of the flashing is smooth and has no water break, water pulls underneath and runs down the wall.
3) Flashing Projection Is Too Short
If the flashing ends too close to the façade, water falls directly onto the wall and leaves dirty streaks.
4) Poor Joints and Sealing
Water usually enters exactly at the joint near the wall. If the connection has gaps, streaks and efflorescence may appear later.
5) Flashing Is Installed, but Water Still Runs Down the Façade from Above
If the gutter or canopy does not drain water properly, window flashing will not solve the problem — the issue is higher in the system.
How to Do It Correctly: The Simple Logic — “Water Must Not Touch the Wall”
To keep the façade dry:
flashing must have an outward slope
there must be a water break, or drip edge
the flashing projection must be sufficient so water falls away from the wall
the joint with the wall must be sealed neatly and reliably
upper elements, such as canopies and gutters, must not direct water onto the façade
Why This Is Especially Important for Insulated Façades
In an insulated facade system, weak points become visible faster: water enters connection areas, stains and efflorescence appear, and the overall appearance gets worse. That is why Facade insulation must always be combined with proper flashings and drip edges — they are part of one protective system.
How the Finish Helps These Details Look Neat
Even good flashing will look worse if the joints around it are uneven and the geometry is poor. That is why areas under windows and around details require a material that is easy to adjust and practical to maintain.
In such places, KORDEKO flexible tile (PletaFlex) is often used so that the details look neat and the façade keeps its appearance without constant “washing off streaks”.
Mini Checklist: How to Check a Drip Edge and Flashing in 2 Minutes
Pour water onto the top of the flashing: water should drain outward, not “crawl” underneath it.
Check the lower edge: is there a water break, or drip edge?
Look at the façade under the window after rain: are there regular streaks?
Check the joint near the wall: are there any gaps or peeling sealant?