WUFI

Hi David,

As Manfred said, the Substrate Classes (Class 0,1,2 & K) account for the differences you are talking about between materials. WUFI Bio doesn't do any "smart" or "automatic" interpretation based on the material, it is strictly what substrate class you select that dictates the LIM curve ...

Yes, when the temperature is less than the dew point temperature you will have condensation.

The amount of condensate (i.e. liquid water from condensation) will depend on the amount of moisture present in the air and how long this condition exists.

Hi David,

Setting an 'indoor' climate which matches the outdoor temperature and humidity would be another way to do it if you're only interested in the outer leaf. Obviously this would inherently assume very high ventilation rates in order to have the cavity match the exterior conditions.

In ...

Just to clarify what Daniel was saying, the porosity and maximum saturation are linked in the sense that maximum saturation occurs when all of the pores are filled.

Therefore, if you have a material with a porosity of 24% or 0.24 m3 of air/m3 of material, that means that the maximum amount of water ...

Hi David,

Your approach in either case is correct. If you're assuming a very highly ventilated cavity, you can just ignore the layers outside the cavity as you said, just make sure you also turn off solar radiation in addition to the parameters you mentioned.

If you want to simulate the cavity and ...

Since we our two WUFI courses last week (in Glasgow and Dublin), I've received some questions by email. Rather than responding directly, I'll post the responses here so hopefully others will benefit as well:

When using a Psychrometric chart, is the temperature measured in a room equivalent to wet ...

There will be a WUFI Pro Heat & Moisture Simulation Workshop offered in Dublin on the 30-31st of March, 2011.

For more information, or to register, please visit:

http://www.josephlittlearchitects.com/blc_training.html

Hope to see you there!

~Calina

A couple of things:

Lee,

In response to your question: “Is it right to say that as a result of the hygroscopic properties of the insulation that condensation will not be a problem?” – be careful with your interpretation.

It is true that with hygroscopic materials you are unlikely to get actual ...

Lee,

You have to be very careful when looking at the moisture content graphs. It makes a difference whether the material is hygroscopic or non-hygroscopic . Only hygroscopic materials absorb moisture out of the air based on humidity levels. Non-hygroscopic materials remain dry until condensation ...

Hi Lee,

First off, you should be aware that the timber studs in the wall can create 2D effects that WUFI Pro (1D) won’t demonstrate. If you need more accurate simulations, you should be using WUFI 2D. According to the Fraunhofer’s testing, if there is insulation on the outside of the studs (i.e ...

Hi Paul,

In response to your questions, I agree that it is difficult to find concise information.

For any information regarding material properties, your first approach should always be to contact the manufacturer and see if they can provide the information to you. It's likely they can't, but it ...

We now have a forum up and running to serve the quickly growing number of WUFI users in Ireland.

We are hoping this forum will serve to keep disussion going about the use of WUFI in Ireland and answer questions that arise from Irish simulations.

Please feel free to post any comments or questions ...