Pros:
Intact Original Windows
Older windows have a way of telling a story about a building’s history, and, as with many architectural features of old buildings, can be very beautiful. However, they are not without their pitfalls. They can present certain problems down the line, especially when said windows are constructed using wood, which is prone to warping compared to more modern material options. This warping can mean a less airtight seal around your windows. This will decrease the energy efficiency of heating and cooling systems in your home or office.
When you install a secondary glaze on to the inside of your existing windows, you’re sealing them against wasteful leaks, while keeping your original windows. This is a major boon to the owners of older buildings in particular, many of whom wish to maintain a sense of architectural history and integrity to their property.
Price
When compared to dual payne replacements, which remove the entire window and replace it with double payned-insulated glass, which is separated by a layer of insulating air, secondary glazing is much less expensive. Because the original window is left in place, there are minimal architectural alterations that need to be considered, which translates to lower costs to the consumer overall.
Reversibility
The simple fact is that sometimes, people change their minds. The good news is, in the event that consumers change their mind about a secondary glazing job, they have this option. One simply needs to call the professionals back, so that they can then reverse the procedure relatively easily.
Cons:
Reduced insulation
While secondary glazed windows are certainly more efficient windows that have gone untreated, they still offer less in terms of insulation compared to double-glazed window replacements, by about half.
Condensation
There is a slightly higher risk of condensation-related moisture damage with secondary glazing when compared to double payned windows because the seal is not quite as airtight. However, as with the reduced insulation, it is still better than leaving single payne windows.
Every situation, like every building, is unique, and depending on the unique factors surrounding one’s home or office, secondary glazing may or may not be the best available option or investment. However, for other buildings, especially older ones, secondary glazing may turn out to be be the only option as a full dual-payne window replacement is simply not available due to building codes, local ordinances, or any number of other factors that need to be taken into consideration.