Durisol says that stucco can be applied directly to the surface. This wouldn't allow for a drainage gap. I'm interested in comment on how this would perform in an area with lots of rain.

I'm also wondering how it would perform with plaster applied directly to the inside.

Thanks for any info

Hi Vermonter, I have completed many Durisol projects with Stucco finishes. Most have been synthetic (i.e., Dryvit), but a couple had the "traditional" 3 coat system which ends up a little over an inch thick. In both scenarios, the finishers still used a glass fibre mesh (Durisol has an extensive stucco document to follow). I'm not a stucco guy, but none of the projects have experienced any trouble. We are in an area where we get about 20 inches of rain per year, so not extremely wet. Where are you located? I'm not too sure of your question regarding the drainage gap - are you talking about EIFS, or about stucco directly on ICF's that typically do not provide a gap? I know of a project in Healdsburg CA where they did the traditional paper/lath and mesh which does provide a drainage plain. We don't do a lot of plaster interior finishes (b/c of the cost and availability of plasterers - not really common around here in Central/SW Ontario). But I have seen and heard from many in the field out near Idaho/Washington/California that interior plaster is the norm on the Durisol interior surface, directly applied. I can get you reference names if need be. Hope this helps?

I have worked with builders on the west coast with Durisol + stucco. The normal "safe" practice is to incorporate a drainage plane regardless of the substrate (whether it is Durisol, wood sheathing, polystyrene, etc). Using building paper instead of housewrap is better because it will debond from the stucco and create a drainage plane. Incorporating a drainage plane will mean you will need a metal lath for the stucco, but that is pretty normal and will help to prevent joint cracking. See the following link for some good information on stucco, drainage planes, etc.

http://www.ashireporter.org/articles/articles.aspx?id=1493