Tiles (Fliesen) as a cladding

[PScharfA]

Hello all,




has anyone experience with doing calculations with a construction with tiles on the outside of a wall.
They are often times as listed heritage here and we want to study the appliance of a interior insulation.

The WUFI database currently lists no component which resembles such tiles but there is the functionality in the Surface Options under "Moisture" and reflects a sd-Value of sd = 2 m



This needs to be applied on a existing construction, such as plaster.
The simulation shows no reasonable results though, because the wall would (even without interior insulation) show 95%+ overall water saturation after 10 years. Rainwater seems to accumulate and never evaporate to the outside.






There must be a better way to resemble these facades within WUFI.
Does someone have experiences? Thank you very much! Greetings

[PScharfA]

The DIN 18515:2014 Appendix A might give a hint on how to approximate the outer layer (at least diffusion resistance) in dependence of the joint/tile ratio and diffusion resistance of the mortar.



The water absorption coefficient might be tough to approximate.

[Christian Bludau]

The sd-value for tiles was measured for small format bathroom tiles and is an effective sd-value containing the tiles itself and the joints, similar to the Appendix from the standard. Problem for using this at the outside is, that adapting an sd-value between the surface and the climate, as it is done in the boundary conditons, does not have an effect on the rain. So here the rain can be absorbed by the wall but the drying process is happening by diffusion, which is reduced by the sd-value. So it is not recommended to use the sd-value in the boundary conditions for a situation where driving rain should be accessed.

In WUFI 2D I would add the tiles an joints as a surface material on the construction, similar to this clinker facade:

Clinker façade with bricks and joints

surf.png (17.89 KiB) Viewed 5511 times

Christian