Articles Codes & Standards
The Window Geek: The impact of code changes

I’m often asked by specifiers how the new energy codes in B.C. are impacting the window industry. My response is, how is it impacting window specifiers? Bottom line, if you are a specifier and are not aware of the impact energy codes are having on the window industry, you are likely going to discover this when your project goes to tender. By that time, it is hard to make design changes.   

I’ve created a proposal that creates awareness of conflict. It’s simple. Write a list of all the compliance measures that a window is required to meet and then rank them in order of importance. Usually, I start with life safety, then what can impact occupancy and then the nice-to-have features. By doing this you can start a framework for decision-making when conflicts arise and when two conflicting items prevent you from being 100 percent compliant.  

For most buildings in B.C., especially multifamily buildings, there are four main items that come up all the time. These are guard load, energy, air/water tightness and acoustics. When working with these four design requirements it is important to look at them as a whole system as opposed to individual items. In the past, it was common to design around each one separately but as requirements have become more stringent it is important to look at them together.  

So how does a specifier combine these requirements into one specification and potentially one product? The challenge a specifier might have is that each item generally has its own specialized designer who is required to design and approve the final result. This can cause a bit of conflict especially when the specialized designers don’t coordinate their designs. Think of how an architect and structural engineer work together. We now need to combine, structural engineers, energy advisors, building envelope consultants and acoustical consultants into the coordinating process.

Recently, I had to deal with two projects where the acoustical requirements were dictating a glass type, thickness and air space that impacted both the ability to meet a life safety requirement and the energy code requirement. The glass thickness needed for acoustics was not available with the low-E coating needed to meet the energy code requirements. The laminated glass needed for acoustics did not meet the guard load requirements to meet the life safety load calculations required by code. The air space specified for acoustics, in combination with the glass thickness required for wind load, resulted in the overall IGU width not fitting in a standard window frame.

As you can see, building acoustics is a common issue that is causing other code conflicts to not be met. A compromise needs to be made somewhere and someone needs to be capable of making this decision. So I recommend a designer who oversees all aspects of a building take time to consider how to evaluate each one in order of importance.  

I spend one week every two years reading the building code front to back in order for me to know what is actually in the code and more important to use parts of the code to help navigate conflicts like this. For example, the acoustic requirements that impact a window are not actually in the B.C. Building Code and are required through the development process as higher densification occurs and buildings are being built closer together and on busy corridors. Not to say it is not important, it is just less important than other aspects that are required to meet life safety and/or occupancy.  

Anton Van Dyk is vice-president of product development and innovation for Centra Construction Group.