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John Bunzick, CCS, CCCA
Senior Member
Username: bunzick

Post Number: 373
Registered: 03-2002
Posted on Tuesday, June 28, 2005 - 07:49 pm:   Edit PostDelete PostPrint Post

I'm working on a project on the central coast of California which has some 3-coat stucco. I'm not well-versed in stucco. We have specified 2.5 lb self-furring diamond lath (over plywood sheathing), and the contractor has submitted "stucco netting", which is the hexagon woven wire lath. It doesn't seem to me to be much of a product, though I see it being used around here on other commercial projects. Have we over-specified by asking for the diamond lath? Are there specific things to be concerned about with the "stucco netting" (even the name makes me skeptical)? We also asked for fiber reinforcing in the scratch coat. Necessary?

I'd appreciate input from those who've done projects in this area. In New England, stucco's pretty rare.
Anonymous
 
Posted on Tuesday, June 28, 2005 - 08:29 pm:   Edit PostDelete PostPrint Post

The 2.5 lb self-furring lath should be quite adequate for the job; I have worked in California for a long time, and would not consider it overkill at all. Same for the fiber reinforcing. Unless this is a public school, you should be fine. There is a provision in the California Building Code for projects under DSA (Division of the State Architect) jurisdiction which does not allow self-furring lath over sheathing.
William C. Pegues, FCSI, CCS
Senior Member
Username: wpegues

Post Number: 406
Registered: 10-2002
Posted on Wednesday, June 29, 2005 - 09:52 am:   Edit PostDelete PostPrint Post

John,

Stucco these days is so far away from what it used to be that I no longer write it as a generic description of materials like you would write plaster. You can get it that way, but you are as likely to get a no name system that is just put up by an installer.

Most stucco manufacturer's consider the basic portland cement type systems as their bottom end. They are not only use fiber reinforcement but also various acrylics and other elastomers to modify the mix to make it more flexible. And then there is the finish coating that is applied which can also range from a very basic coating to one that is also more eleastic and crack resistant.

Unfortunately, when you get into the literature on most of the manufacturer's, you are looking at data sheets of bags of this and that and you have no idea what they are talking about, or which goes with which.

One of the better organized presentations of "Stucco Systems" where they present it as systems and then list the products that make up the systems is Parex. Yes, they are an EIFS manufacturer, but they acquired a very large stucco manufacturer, and the 2 are treated very separately. In fact, if you go to their web site, the first thing you get is a choice to go into their EIFS area or their Stucco area.

We had one project here where an owner had brought in a new project manager for their side and he suddenly wanted to start using stucco. And he wanted to use the system just like he used and had installed on a previous project in the mid-west a couple years ago and described it incuding the manufacturer. No one could run down what this was, or confirm what was actually used, not even the supposed manufacturer. It was supposed to be a one coat system that he was just raving about how great it turned out. It was actually Parex and a local installer here that joint finally found out what the product was. It was the manufacturer that the owner's project manager thought it was, but the system actually installed was one of the higher end 3 coat systems with elastomeric modifiers in the mixes as well as the face coating. Obviously why it was performing so well.

Anyway, if you are looking for a good presentation on systems and what they can do for you, as well as a good reference, check out the Parex web site.

www.parex.com

Their technical people are excellent, and they have local representatives in most areas. They are great in that they don't press their specific product, but come to the table to see that you are informed when you ask for assistance.

William
Anne Whitacre, CCS CSI
Senior Member
Username: awhitacre

Post Number: 214
Registered: 07-2002
Posted on Tuesday, July 05, 2005 - 01:21 pm:   Edit PostDelete PostPrint Post

John-
stick with the self-furring lath. The "stucco netting " or chicken wire isn't self-furring and will not provide the mechanical bite for the stucco. Also, use the fiberglass shorts in the mix; its typically 1 to 1-1/2 pounds per sack of cement. You should be getting 7/8" stucco (three coats) minimum; some SoCal firms use 1 inch thickness.

We do stucco all the time (and I have it on my house). you can email me directly.

Anne

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