We built our own ICF home and didn't finish the exterior basement wall because of a lack of funds.  Well, it's been up about 4 years and would like to finish it.  

Could someone give me instructions on how to clean it and finish it off?  I'm thinking about using Grailcoat or if someone knows a cheaper waterproof brand, please let me know. 

Are there any videos that show how to properly stucco icf?  Do I need to attach a mesh to the wall to get the stucco to stick or should just cleaning it be ok?

Thanks.

[email protected]

What kind of stucco? Traditional 3 coat or Acrylic?

Ron, first and foremost you need to remove the yellow powder on the ICF. No stucco is going to stick to that whether it be traditional or synthetic. The yellowing is due to the UV degradation from the sun.

You need to rasp it off. Rasping has 3 effects: 1. it cleans off your ICF 2. it takes out minor un eveness 3. It prepares the ICF to receive the stucco coat by making the surface a bit rough.

These steps you need to take regardless of which kind of system you choose! I would research what system you like, buy it, prepare and clean the wall, then apply the stucco. Don't clean the ICF and then let it sit for 2 or 3 months before installing the stucco. The UV degradation will have taken place again - maybe not to the degree it is now but it will make a difference in the adherence or non-adherance of the stucco. Hope this helps.

Grailcoat needs a clean surface to start.  Remove all the yellowing and rough the surface for a secure bond.  It is a waterproof 3 step system that requires mesh.   

We helped a do it your self guy get started we thought we would be more involved but he was pinching pennies and his walls yellowed.  I loaned him my 3500 psi pressure washer we use to clean equipment and wood forms with .  with a wide spray he was able to quickley clean things up  If you get a narrow tip or get too close it will cut thru to the concrete

timothale, while I do like the ease of working with water pressure to put this equipment into the hands of an inexperienced guy is not a good idea. As you have mentioned it is easy to cut right through the concrete. I would also submit that if you just remove the yellowing powder you still have not roughened up the surface. If you increase the pressure or change the tip you cannot achieve a "uniform" wall plane.

Rasping is still the preferred method, and yes, it is slower but more exact and does everything to supply a perfectly prepared substrate for stucco.

What are the best options for parging ICF?

Our brick and siding has been installed and our below-grade waterproofing and drainage was done last year. We just have the parging left and I was considering doing it myself.

I was looking at Grailcoat but I'm not sure how well it will stand up to a Canadian winter. Plus, I thought that there may be some other proven products that people here have experience with.

Thanks.

Brian.

I have heard of grailcoat and like what I hear. Has anyone used it and can they comment on their experience?