These are some of the most frequently asked questions about stucco and other exterior wall claddings.
Q) I’ve read stories where the EIFS has led to problems with mold. Why is that?
A) The single biggest cause for failure in any exterior wall system, and that can lead to mold in the walls, is the improper installation of the weather barrier. Having a contractor that understands the need for a complete building envelope is not just important, it is critical.
Q) Why is my stucco cracking?
A) Hairline cracking on any stucco product that has concrete as a base is quite common and may not be a symptom of a system that is failing. Concrete is rigid and as the house settle and moves the concrete may not be able to move enough to keep up with it. This results in hairline cracking – which are particularly noticeable around the weakened areas of the wall penetrations, such as windows and doors. (Steps we can take as applicators to reduce – but not eliminate – the problem are; use fiber in the concrete to allow for more movement, add reinforcing diamond lath to the corners of windows and doors where cracking is most common, addition of the appropriate expansion joints and use of an elastomeric product – when using an acrylic rather than cementious finish). Major cracking, where you could slip a dime between it, may be indicative of, A) System failure due to improper installation. B) Larger shifting of the base structure due to settling. Cracking in EIFS is very uncommon but not unheard of. Two possible causes would be A) Wind load, in the case of a very large building. B) A situation where the EIFS is too close to another system causing the underlying, and weaker foam, to give way. An example would be a concrete step that is poured high onto the wall system, (common but not up to code), and if settling of the concrete step occurs it might create enough tension to break.
Q) How do I take care of my stucco?
A) With every system there is a maintenance manual that spells out the proper requirements. Simply search on Google for “Adex”, “Sto” or “Dryvit” maintenance manual. (These are the most common acrylic products in Canada).
Q) What is that salty looking deposit that shows up on my finished stucco and how do I get rid of it?
A) Efflorescence is a condition where white (salt) deposits form on the plaster surface. The formation of salts is usually a sign of excessive amounts of moisture in the concrete. While it can occur in EIFS it is more likely to occur in stucco products with a concrete base coat rather than synthetic base coat. I have found its appearance to be a very rare. Salt deposits on the surface can develop from soluble compounds within the adjacent masonry or in the soil. In the presence of water, these compounds gradually migrate to the wall surface, where they remain when the water evaporates. While not harmful to the material, its appearance is unattractive. Refer to the maintenance manual for cleaning. Its appearance does not signify a failure with the system.
Q) Can I repair stucco myself?
A) Yes, but do your research and be aware that your biggest challenge will be color matching, (I still struggle with it on particularly tough matches). Proceed with caution, as a small patch could become a big problem. Previous Hawk and Trowel experience are a definite asset.
Q) Why is my window leaking?
A) There’s always a question of responsibility when it comes to leaking windows. Whose fault is it, window applicator or stucco? As stucco applicators we ask, “Who was first in”? If the window installation was not performed to meet the Wall and Ceiling Association recommendations, (specifications that permit us to complete our system), we must sometimes improvise to insure a proper weather barrier. This is not typically a major issue as where there is a problem – those with the proper experience and conscientious approach – find effective solutions. Regardless – it will have to be a stucco contractor that does the initial inspection and that inspection will likely involve the removal and patching of some stucco that, if no longer under warranty can involve a fair bit of expense and the simple act of caulking almost never resolves the problem. If you decide to caulk begin by caulking under the window flashing on top of the window and test before doing anything further.
Q) What’s the difference between EIFS and Stucco?
A) There are many different components to an EIF system versus a “sand and cement stucco system” but the one that stands out as most important for the process of comparison is that EIFS uses Expanded Polystyrene and is produced by bonding coarse beads into rigid foam plastic boards and has an R-value of 3.7 per inch. 1.5 inch is the recommended minimum providing 5.5 R-value. The sand and cement product has no measurable R-value and therefore no energy savings to save the cost of installation over time.
Q) Can stucco be painted?
A) Yes all forms of stucco can be painted – but they should not all be painted the same way or with the same products. Ask a stucco supplier for their recommendation based upon the type of stucco you’re going over.
Q) I’m considering buying a house, (or commercial building), with EIFS or stucco on it. Should it be inspected?
A) Yes I would have a building inspected that I was unsure of, but by whom. It takes a practiced eye to understand what you are seeing.
Q) Is there an economical way for me to update my existing stucco?
A) Yes! The main concern when updating your stucco from “stone dash or California finish”, to an acrylic finish is whether or not it has been painted. If it has been there are additional issues to be dealt with but not insurmountably. The primary concern regarding an existing system would be ” Is the existing weather barrier intact? ” If there are concerns with moisture penetration, I would hesitate before proceeding! As the applicator agreeing to go over an existing system, I can only warranty my work, and underlying problems may be beyond my capacity to know about!
*For further enquires please email me – bearing in mind I may add your Q and A to this website.
