Acrylic Coating on Exterior Wall

[Civil Student]

Good Afternoon,

I am a Civil Engineering student, and I am currently conducting a Hygrothermal study-case analysis for a report using WUFI ORNL. I am new to WUFI and learning as I go, so I had a couple of questions I had not been able to resolve on my own.

My analysis is based on the comparison between some building scenarios in which I need to add an exterior layer of an ACRYLIC COATING for the wall exterior, specifically "Brush Coat" (from Durabond) (http://durabond.com/wp-content/uploads/ ... shCoat.pdf) and "THOROCOAT" (acrylic waterproof coating for above grade concrete and masonry from BASF) (http://www.brockwhite.com/files/Resourc ... 0123PD.pdf). This layer will definitely affect the behaviour of my wall assembly when I run WUFI. However, I was not able to find in any of your categories any material that is an acrylic coat. Would you please be able to provide me with some suggestions or recommendations for this? Maybe, a material already in the database that would resemble as close as possible the properties of these acrylic coatings?

Also, in the most interior layer of my wall, I need to add a layer of paint to try to simulate as closely as possible a real scenario, but I have not been able to find that in the categories from the WUFI program. Would you be able to make a suggestion with this as well?

Thank very much in advance for all the help and input for this subject!

Regards,

Gabriel

[Christian Bludau]

Hello Garbiel,

in the case there is no rain on your surface, you can enter the sd-value or permeance according to the data sheets in the surface transfer coefficients.

if your coating has an a-value and there is rain, you have to generate a layer. Maybe take some acrylic render, set the water transport coefficients for suction and redistribution to "generate" and enter your a-value (take care of the unit). Further you have to adapt the water vapor diffusion resistance factor or permeability.

Christian

[Thomas]

Hi Gabriel,

please see WUFI's online-help topic "Reference | Surface Transfer | Surface Coatings" for additional discussion of Christian's suggestions.

Regards,
Thomas