storm door picture

Storm Window Measuring & Installation Made Easy

Exterior Windows

Storm window sizes are determined by measuring your existing window opening as shown ​below. Record smallest opening width A first and opening height B second. Round down to the nearest 1/8".
LARSON® Storm Windows can be installed Outside Mount or Inside Mount, or you can have the windows made to the exact tip-to-tip measurement desired.

Many kinds of windows can be installed Blindstop (inside mount) or Overlap (outside mount), or you can have the windows made to the exact tip-to-tip measurement desired.​

how to measure for a storm window
OUTSIDE MOUNT
Overlap
Overlap Mount Storm Window
​INSIDE MOUNT
​Blindstop
blindstop storm window

​Ordering Your Exterior Storm Window

outside storm window

Outside Mount Installation
Overlap

Measure your existing window opening listing width first and height second. One inch will automatically be added to the width and 3/4" to the height allowing an overlap for a proper fit.

inside window

Inside Mount Installation
Blindstop

Measure your existing window opening listing width first and height second. The window will be automatically downsized to ensure proper clearance and fit.

flush storm window

Flush Mount Installation
Premium Series Windows

Measure existing window opening and record width first and height second. Necessary unit size adjustments will automatically be made.


Interior​​​ Windows

insider™ windows install on the inside of existing windows. They cut energy loss by up to 50%, reduce drafts by up to 48% and cut outside noise. They’re perfect for older and historic homes because they don’t change the look of your home. Since they’re attached from the inside, they will not weather, and can be easily removed for the summer months or for cleaning.

insider storm windows

Measuring

Interior storm windows are custom built to ensure a tight fit. Sizes are
determined by measuring your existing window opening.

• Measure opening width at three locations (top, center, middle)
• Measure opening height at three locations (right, center, left)
• Round the narrowest width and the shortest height down to the nearest 1/16" and provide these dimensions when ordering; window panel is downsized to fit opening given.

 

NOTE: 1" inch depth is recommended for installation of the LARSON Insider Storm Window. For out-of-square openings, 1/8" tolerance.

 

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