Hi, I've built myself an ICF house in Scotland and am looking for advice on render finishes. In particular I am looking for a stucco type finish (normally referred to as a wet dash/roughcast/harl finish here). These types of finish are not common on externally insulated walls here, the most common finish is a acrylic/silicone flat finish (maybe 1-3mm grain) or a dry dash stone finish. Has anyone used the Parex system on their build, or an equivalent themselves? What thickness of render, how many layers, what mesh? Did you spray it or throw with a trowel? The samples of render I have had already from various companies show the acrylics are very thin and flexible, I would love to see examples of stucco on older ICF builds and see how they have done.

Some people use Synthetic Stucco usually called EIFS (Exterior insulation and finishing system) products. Brand names like Drivit, Sto, Rwall... The gray basecoat is applied with a screen mesh and overcoated with a thin colored coat of "finish". There are advantages and disadvantages to EIFS.
For the thicker "real stucco" I would guess you would need to use metal lath to hold it up, plus mechanical connections to the wall.

These are a very good ICF finish, exterior cladding. I used Total Wall on my own house, inside and out.