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Best Practices:
Don’t Let a Carpenter Fix Your Car (I)

Wednesday, August 6, 2014

More items for Good Technical Practice

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One issue we frequently encounter in the building community is the “But It’s Just Paint” Syndrome. That’s where the complexities of good painting practice are ignored—because, after all, “it’s just paint.”

This thinking can run deep in homeowners’ associations and the building design/engineering firms they hire for maintenance and retrofit work.

We know precious few engineering firms that retain staff who specialize in commercial/architectural coatings. And yet, these firms are consigned by naïve property managers, who don’t recognize that years of experience or training are required to choose the right coating system, write a strong paint spec, and assure a successful paint job.

Condo Complex
Images: MPI

Property managers do not generally recognize that years of training are required to choose the correct coating system and assure a successful paint job.

In these situations, asking an engineering firm to write repaint specs can be like asking a carpenter to fix your car. And the result may be a very costly premature failure.

The Case of the Bad Repaint Spec

Since 2011, the British Columbia Office of Housing and Construction has required condo homeowners’ associations (or Strata corporations, as they’re called here) to obtain depreciation reports every three years

The goal is to help owners understand and plan for the costs to maintain the common property over a 30-year period. The reports also create transparency for prospective buyers about the facility's condition.

The report must contain a physical inventory of common property and assets; anticipated maintenance, repair and replacement costs for common expenses projected over 30 years; and a financial forecasting section.

So since 2011, the local engineering firms have had a bit of a boom in business. And not just in writing the depreciation report: Once it’s done, they become the prime candidate to do the work that follows, from writing the repair/maintenance specifications to managing and inspecting the work.

Knowing What You Know

But as noted above, an engineering firm that’s a crackerjack at evaluating and writing specs for the general building envelope may know precious little about paints and coatings.

And as the great humorist Mark Twain once noted: “It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so.”

Efflorescence

Efflorescence was obvious—now and 10 years earliernext to balcony ceiling vents.

That’s what the inspector found when a savvy property manager called him in to review the paint portion of the specifications that followed the engineers' depreciation report.

Déjà Vu

The inspector started with a careful inspection of the building. Then, upon review of the specs, he found a few discrepancies between what he considers good painting practices and the building engineer’s choices.

The first problem involved the soffits and decks, which the specs did not mention. The first balcony visited had water pouring through the soffit into a bucket on the homeowner’s deck.

“This has been leaking for years,” the glum homeowner observed.

In fact, it had been leaking for a decade, which the paint inspector knew because he had been at the building 10 years prior, and the soffits were leaking back then, too.

He also noted similar issues on other balconies/soffits and observed various degrees of flaking and efflorescence around the vents—the same efflorescence he’d seen 10 years earlier

Fix It First

The cardinal rule of maintenance repainting is: Don’t even think about painting it again until you’ve fixed the problem that caused the failure in the first place.

The inspector’s report to the property manager noted this in slightly more eloquent terms: “If the above conditions are not corrected or investigated in regards to the cause, future failure on the ceilings will continue to occur.”

Freshening Factory Finishes

Next came the aluminum railings. The original factory-applied finish was still in excellent condition; even so, the specs called for a repaint to freshen up the color.

Aluminum Railings

Factory-finished aluminum railings were in good shape, but the repaint spec recommended topcoating directly over the factory finish—not a good idea.

The inspector had no issue there. However, the engineer’s spec called for applying a coat of a gloss exterior alkyd approved under MPI #9 directly to the original finish.

In our experience, no conventional exterior alkyd can be successfully applied over an intact factory finish; a transition coat must precede it or the alkyd topcoat won’t adhere, and the frustrated owners would see their new paint job peel and delaminate in short order.

The metal roofs also had a factory-applied finish to which the building engineer was specifying the same MPI #9 without a transition coat—with the same potential for premature failure.

Cracks in the Stucco

Next were the stucco surfaces: These were unpainted but exhibited extensive hairline cracking. The building engineer called for two coats of thin-film exterior latex such as a product approved under MPI #15.

The inspector's first issue was with specifying just two coats. If the stucco surfaces were previously painted and intact, MPI’s Repaint Manual says two coats are accpetable. But unpainted stucco has to be treated as new, and MPI’s Architectural (new construction) Painting Manual calls for three coats.

Stucco Cracks

Stucco surfaces showed extensive cracking. The specifier called for two coats of a thin-film exterior latex had been prescribed. The inspector disagreed.

More important, conventional thin-film latex can’t fill the cracks. A far better choice would be a product approved under MPI #40 Latex, Exterior, High Build, These are tested to verify they can fill holes up to 1/8 inch in diameter, with a film build of 10, 12 or even 15 mils in two coats (versus the 3-5 mils attained with conventional latex).

Rusting Rebar

The last item on the list: rusted rebar. The concrete decks had been constructed by pouring concrete over rebar, and small pieces of metal were left behind just under the concrete surface. When moisture condenses on the ceiling surface or the deck leaks from above, these small pieces of exposed metal are subject to air and moisture—a recipe for corrosion.

The building engineer’s spec had called for grinding and spot-priming these with an alkyd stain-blocking primer such as a product approved under MPI #136 followed by a coat of a well-known manufacturer’s product that is also a stain-blocking primer.

The paint inspector took exception to that approach: Stain-blocking primers have no anti-corrosive properties, and MPI #136 isn’t even designed for metal surfaces. Some type of anti-corrosive primer is a must for this application.

Tomorrow: Making it Right

Editor's Note: This article was written by PQA Inspector Clayton Des Roches and is reprinted with permission from the MPI (Master Painters Institute) newsletter. MPI content describes best practices for commercial, institutional, and light industrial painting.

   

Tagged categories: Architectural coatings; Certifications and standards; Coating inspection; Condominiums/High-Rise Residential; Maintenance coating work; Master Painters Institute (MPI); Specifiers

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