WUFI

Hi Nils,
you can model the cooling effect by using a source/sink in WUFI and defining it as a heat sink in the corresponding source file. In this file, the cooling capacity should be specified over the annual course using negative values to represent the cooling effect. There have already been a few ...

How would you model this layer which contains in the same planes Air, insulation and metal deck? Would you recommend to model in WUFI the insulation in the flutes of the metal deck as a continuos insulation layer? Should we ignore all gypframes support, galvanized metal deck, etc in a WUFI model ...

Hi Alberto,
I agree, but from a material perspective, lime plasters are often applicable on both interior and exterior sides.
Many applications the basic hygrothermal properties are comparable, and for interior applications, the vapour diffusion resistance (µ-value) is typically the most relevant ...

First of all, I would recommend having a look at the WUFI guideline on typical constructions, which also explains the correct handling and interpretation of simulations (including boundary conditions and evaluation). There you can find a basement example:
https://wufi.de/en/service/downloads ...

Hi Laura,
the models are included in WUFI Pro 7 in the user-defined climate tab of the interior climate.
There select the needed attic model from the template pull down.
The RH is derived as a additional moisture load depending on the outdoor humidity.
In here you can rise the values of the ...

When modeling a floor or slab in contact with the ground in WUFI 2D, the boundary condition should not be treated like a standard exterior surface with air temperature and humidity. Instead, the ground boundary needs to represent the coupled heat and moisture interaction with the soil.

A good ...

Hi,

to add a new product to the WUFI database, it is recommended to use an existing, similar material as a basis.
First, open the material database and select a material that is comparable in terms of composition and hygrothermal behaviour.
Do a right click on this material and select "New material ...

Initial conditions:
In many cases, it is acceptable to use the default initial conditions (e.g. around 80 % RH and 20 °C), especially if no better information is available. These values represent a reasonable approximation for materials close to equilibrium moisture conditions.

If you have ...

Hallo Björn,

Luftwechsel in der Luftschicht:
Deine Beschreibung deutet tatsächlich auf eine deutlich erhöhte Luftbewegung hin. Allerdings ist die Übertragung von typischen Luftwechselraten (z. B. hinterlüftete Fassaden) nicht ohne Weiteres möglich, da der Luftaustausch stark von Geometrie ...

Could you please post the regressive line for each model (green line)?

These models are included in the WUFI Pro 7 user defined climate section. You can find them in the "Template" pulldown.

Christian

Dear Alberto,
you can search for “lime” in the WUFI material database and select a suitable or similar lime plaster from the available entries.
Christian

Dear Guillaume,
the behaviour you observe is mainly related to how the roof covering is represented in the model.

In WUFI, roof tiles do not simply act as a vapor diffusion resistance layer. Instead, they modify the exterior boundary conditions acting on the underlying construction. In particular ...

Dear Guillaume,

for rising capillary moisture there is, to my knowledge, no generally applicable characteristic value (e.g. in kg/m²·a), as the amount of transported water strongly depends on the pore structure of the material, the pore size distribution, and the degree of saturation.

As a ...

Hi Josephine,

if the modelling direction is not explicitly defined by the problem statement, a horizontal section is usually assumed in WUFI 2D. In that case, the model represents a cut through the wall in plane, for example to study horizontal moisture transport or local effects.

However, it is ...

Hi Nick,

from my perspective, it would be more appropriate to set up the model in such a way that it can also be evaluated reliably with an initial relative humidity of 80 %, rather than reducing the initial moisture level solely for numerical reasons.
The observed B1/B2 balance discrepancies at 80 ...