Mullion Window Dividers

Indow Mullions

An Indow Mullion is an aluminum ‘H’ shaped profile that installs inside of a window frame to divide large window frames into smaller, more manageable units. Having two small inserts in a window versus one large insert are ideal in applications where the resident will want to easily remove the lower insert to open window for seasonal fresh air. The smaller inserts allow for easier storage when not used. 

Mullions will need to be used for very large windows which exceed our 6 ft. x 8 ft. or 5 ft. x 10 ft. panel sheet maximums.
Dividing the window into more than one insert does not have a major impact on the overall cost the project.
The mullion window dividers is typically positioned where there is an existing mullion divider on the original window, so that it looks natural and blends in.

Mullions can divide a window horizontally or vertically.
Indow with Mullion
Mullion Pieces Different Colors
Indow mullion horizontal closeup
Vertical Mullion Installed Indow

                                                                                     Customer Testimonial

Commercial Building Mullions New York
Joseph Casillo was updating his apartment building that included landmark windows. They were over 100 years old and beautiful, but let in drafts and grime. Casillo talked with 3 or 4 different vendors who provide large storm windows, but couldn’t find what he needed. When he spoke with Alma’s Interior Solutions (an Indow insert vendor), he finally found what he was looking for. Working with Indow inserts, Casillo was able to introduce a mullion exactly along the window sash line so that none of the landmark window was obscured.
– Joseph Casillo, Senior Project Manager, 25 Broad St. New York, New York
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