We are ready to apply the exterior stucco to our new ICF home. We have narrowed the search down to two stucco masons.  Problem is , they have differing views on one thing.  One says that stucco over ICF doesn't need the underlaying lath, the other says he won't do the job unless there's lath underneath.  ( this also creates a $9000 price difference). Both are adamant about their opinions. Can anyone offer any advice as to whether or not the lath is truly necessary on ICF ( Amvic)

It sounds like your talking about two different systems. EIFS would be a synthetic stucco sytem that would not require lath (galv. steel mesh) as it is dirrectly applied to the ICF with a fiber cloth mesh. A non synthetic stucco (cement based) would require a metal lath to my knowledge but would not be the norm in todays world. Let us know what type of Stuco you ar using.

Dave

Let me know too
Thanks,
Marc and Kemella

Thanks for the prompt response.

I intend on using a synthetic stucco.  That being the case, I see that you're saying that I would not need a lath mesh.

I have a question and didn't know exactly where to post it. My house is constructed of ICFs and part of the upper construction is with OSB board. I was told that I would need to put felt and lath on the OSB section before putting the brown coat on but over the ICFs, I would not need felt. Now I am told that some regional inspectors want felt over both the OSB and over the ICF's. It all depends on who I get as an inspector, I am told. What is really the correct way to proceed?

Another question: Can I put the stucco undercoat on the OSB and then an acrylic finish over that but put two coats of the acrylic finish over the ICFs?

If you put the felt on the ICF you cannot get into any trouble with the inspector. Technically you really don't need it, but every area is different. In my area you need it. Cost is inexpensive, put it on.

Don't mix conventional 3 part stucco on the framed wall with acrylic stucco on the ICF...it will be noticeable.

Chris, do you put felt *and* lath over ICF, or just felt?

You need lathe, cement basecoat needs something to adhere to and hold it together

Chris, yes that's what I thought, but you just said felt in your post so I was curious.  Wow, that really adds a lot of unnecessary work and expense. But the code is the code, I guess. Must be frustrating.

Chris,

Do you use Tapcon screws into the concrete to hold the mesh and felt to the ICF?  Do you use the diamond mesh that has black paper already attached?

I only show up when it's underway...I'm the ICF guy, not the stucco guy.

I do see the paper tacked with anything, usually roofing nails through the foam, diamond lathe screwed on with Grabber screws to the webs.

I would suggest that you look at a new product that passed the large missle impact test in Fl with a thickness of only as thick as a nickel.  What I would do with a ICF is apply a 2" thick foam(eps 1.5# density) that has a finish like brick, stucco or wood siding then a 2 man crew sprays a 2000 sq house in less than 2 days...
I also use it for the roof, no shingles or "S" tile to ever replace...  It is like srink wrapping the whole house...

No joints or seams and 100% waterproof...

All you need to do is paint it to any color or faux paint it.

Kelly Moore
561.309.2420

Kelly, maybe you could give us a name for the product?

IT is not on the market yet, it is owned by a huge chemical company.  They should allow me to realise it soon, they have not given it a final name yet.  Please be patient it is going to be the next big thing in the construction business...

 

Thanks,

Kelly Moore

561.309.2420

Kelly,

Please keep me informed about your new building system.  Here is my e-mail address: 

alton at auburn dot edu       Replace the "at" with the @ symbol and "dot" with a period.

Kelly,
Is this the same product you were talking up on this forum a year or so ago?
Still trying to get it on the market?
How about some more specifics.