Volume 50, Issue 12 - December 2015

Tales From The Jobsite

Nothing Stays the Same
Learning from Glazing Installation Changes

by Craig Carson

One of the reasons that I look forward to coming to work is that each day is different from the one before. This is true for all of the months and years I’ve been working—this is how our industry changes and how we respond to new ideas.

Think about the ways installing glazing systems have changed. I recall that when a project had a brick veneer façade, we’d install the window framing when the hole was ready, which was after the veneer installation. Of course, the general contractor (GC) was pushing to close in the building and wanted every frame installed quickly so the building could be climate controlled.

I had many projects where the brick veneer didn’t line up with the opening provided by the metal stud and drywall contractor. The offsets made the frames difficult to install. The brick void would act as a cold area, the thermal break would span this void and be subject to the cold air. This would negate the thermal break, leaving the framing cold to the finished room. I’ve even seen ice on thermally broken framing.

Glazing installation means and methods have changed a lot over the past
10-15 years, helping create a more efficient jobsite.
A Better Way

Well, that has changed with the evolution of weatherproofing. It has become a larger and more important factor in energy-efficient construction. We now see frames and glazing installed before the veneers. We also see the glazing systems tied into the weather barrier systems. On many projects, we now provide secondary flexible flashing glazed into the perimeter pocket and apply it over either the liquid allied membrane or some type of paper air barrier (such as Tyvek).

When using a storefront or window in a punched opening, flexible flashing is applied to the frame’s perimeter and to the barrier and insulation is installed to also protect the thermal break. This allows for a superior primary seal for framing the building’s air and water barrier.

This is a significant change from the way we installed systems as few as 10 or 15 years ago. Of course, it also helps the GC close the building earlier, allowing him to start on the interior. It does mean, though, that we need to be more diligent in the placement of the windows if there are panel joints or masonry courses that have to match up to the exterior elevation grid.

There are also added cost issues for this application. In addition to the material and labor cost of the flexible flashing installation, you still need to make one more pass over the skin to caulk between the windows and the adjacent veneer. There are no free rides. To provide a better-designed structure, you are going to add value to the building, and the owner will receive a better product.

An Eye Ahead

New ideas and concepts are always being proposed and implemented. We need to study them and even challenge them to make sure that we understand what they represent and how they will impact our projects. All these new solutions also impact our costs. We need to be sure to understand how they affect us and account for them. Remember, the devil is in the details!


the author

Craig Carson is the regional preconstruction manager for Alliance Glazing Technologies Inc. in Littleton, Colo.


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