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​Selection and Installation Guidance for Storm Windows

  1. When are operable storm windows most appropriate and when should I use a fixed storm window?
    It is recommended that operable storm windows be used over operable primary windows (a sliding storm window over a sliding primary window, for example), especially when installing storm windows over windows in bedrooms where a quick exit may be needed in the event of a fire or other emergency.  Your local building department should be able to assist you in determining if there are any local building code requirements that need to be met when adding storm windows.

  2. Is safety or tempered glass required in storm windows?
    Safety glass, or tempered glass, is stronger than regular glass and is designed to break into small ​"cubes​" (instead of larger, more dangerous shards) when broken.  Local building codes may require safety glass in windows in certain locations, such as near stairs or in bathrooms.  Consult your local building department to determine if there are any local building code requirements that need to be met.

  3. How close to the primary window should a storm window be installed?
    When installing storm windows, it is recommended that the distance between the glass of the primary and storm windows be approximately 1” or more.  This will ensure that the storm window provides the greatest energy efficiency benefit.  Additional distance between the primary and storm windows won’t improve energy efficiency, but may help further reduce noise transmitted through the window opening.

  4. Is anything special required when installing storm windows over metal-framed primary windows?
    When installing aluminum storm windows over metal-framed primary windows, it is important to create a thermal break between the storm and primary window frames to prevent heat energy from being conducted through the metal frames of the windows.  If an overlap mount installation is planned and wood brickmold trim surrounds the primary window, the wood trim can serve as the thermal break.  If a blindstop mount installation is planned, thin strips of wood or plastic may be placed between the storm and primary window frames to create the thermal break.

  5. What is the proper way to seal an exterior storm window?
    When installing exterior storm windows, use a high-quality caulk or sealant to seal the sides and top of the storm window frame to the primary window frame.  Do not seal the bottom of the storm window frame to ensure that any rain or moisture does not get trapped between the storm window and the primary window but can drain at the bottom of the window.

  6. Can I recycle my old storm windows?
    Your existing storm windows may contain recyclable content including glass, aluminum, and vinyl.  If you wish to recycle this, consult your local recycling center to determine if your windows contain any recyclable materials.  Always use caution and wear appropriate protective equipment, including safety glasses, gloves, and long pants, when handling or disassembling your old storm windows.


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