Will Wet Substrate Compromise EIF System’s Installation?

February 2005

This month’s question was either too easy or too scary. Everyone who answered pretty much said the same thing, and those who didn’t answer probably read between the lines and thought we were asking about mold. That said, we are printing the two replies that were received. What follows is last month’s question and some the answers that were submitted after our press deadline.

A condominium project in a tropical climate uses an exterior insulation and finish system (EIFS) with wallboard as the substrate. The substrate is wet, and there is concern that this will compromise the EIF system’s installation. How do you repair it?

Is this a trick question? (1) You didn’t say if paper was used. (2) You didn’t say who designed the system. (3) You didn’t say if it was the contractor’s job (reader) or somebody else. We don’t fix any system that has water damage. We will only replace wallboard as directed.—Anonymous

It just so happens I leave on Feb. 15 to go to the Grand Cayman Island to redo a condo that the drywall was water damaged by hurricane Ivan. We decided the best way to resolve the problem in our case was to tear out the drywall replace it all. but your site maybe a little different. The condo I’m working on had a 12-foot-high wave crashing through it! My crew and I will be gone for 24 days. It will be a lot of work, but at least it will be warm, and being on the beach won’t be bad either!—Kevin Smith, Owner, Eagle Drywall Inc., Ft. Worth, Texas

Your client gets the drywall’s paper wet when he removes wallpaper, causing the paper facing to lose its adhesion and come loose from the wallboard in certain areas. When you go to finish the wall, you notice that the ripple only spreads, even after you’ve applied the mud and cut out the affected area. Is the wallboard no good anymore? Do you have to replace it, or can you make it work? If you think you can make it work, what do you do?

This is what seems to work: Remove any of the loose brown paper that has peeled off using a pole sander (seems to work and is the most efficient). After you have completed the sanding, roll one coat of an oil-based primer (oil-based Kilz works the best because it dries quickly) over the top of the brown paper areas and let the primer dry. The oil-based primer seals the brown paper and allows mud to be applied over the top. Skim and finish as much as needed. Give it a try; it works. —Tom Bland, Van Gogh Inc., Merrillville, Indiana

We normally will laminate over the top—if we can or install new after tearout. I will look forward to see who has a good solution and file the answer away for future use.—Anonymous

First and foremost would be the life-safety issue. Is the construction part of a fire and/or smoke wall? If so, the board would need to be replaced in a manner that complies with the originally intended tested assembly, or, depending on the conditions, an appropriate replacement. The method utilized in the body of the question would not be suitable in this case. ... If it comes down to aesthetics, the direction would depend on the final finishes (paint or wall covering type), and the conditions affecting the appearance, such as severe lighting. A gloss paint, flat paint and severe lighting or thin wall covering would more than likely necessitate either lamination with a thin drywall laminate or replacement of the board. Flat paint in normal lighting situations may allow for providing a level 5 finish/ skim coat.—Brent Allen, South Texas & Lone Start Drywall, Columbus, Ohio