A couple of years ago we worked on a tenant improvement project where the interior frames of the storefront windows had been damaged. The previous tenant had screwed drywall directly to the frame to create a privacy screen.
One of the functions of these frames is to allow moisture that might find it’s way inside the frame to exit through weep holes at the exterior of the window. Holes at the interior of the frame, would allow moisture to enter the interior of the building. The new tenant, a laboratory, had technical devices which were very sensitive to moisture and could be destroyed by it.
To solve this problem we looked at a variety of possibilities including replacing the entire storefront system and reusing the existing glazing. Besides being cost prohibitive, this solution brought with it the requirement to make the building envelope comply with energy efficiency. After discussions with the City, we discovered that the existing glazing that had been installed long before current energy efficiency requirements were in effect, would likely not comply.
The solution that we finally agreed on was to provide a flexible filler for each hole to prevent moisture infiltration and then overlay a thin piece of precisely-manufactured metal over the entire interior storefront frame to finish it aesthetically. It’s been over 2 years and this inventive yet economical fix continues to perform.