Insulating drafty historic windows

Frank Lloyd Wright home with insulating window inserts.Frank Lloyd Wright loved windows. And there’s probably no one who understands this better than the architect John Eifler. He has spent decades restoring Frank Lloyd Wright homes for clients as principal architect for Eifler & Associates Architects.

And now he owns one himself: the Ross House in Glencoe, Illinois in the small 1915 subdivision of six homes planned by Wright’s attorney, Sherman Booth Jr. But most people knew it simply as “The Purple House” when Eifler bought it in 2011.  

It had heavy lilac trim around all the windows.

Eifler knows Frank Lloyd Wright windows from all the houses he has restored: they are casement windows that swing open – often made of beautiful stained glass – with wooden screens on the inside for summer. Since the second-floor windows of the Ross House have some classic Wright leaded-glass detailing, he didn’t want to cover it up in any attempts at insulating the drafty historic windows. He knew it would be impossible to retrofit them with insulating glass without destroying them.

He wanted a simple interior storm window.   

And when he heard about Indow inserts, he knew he had it.  He bought 15 to make the windows more energy efficient without altering them.

“That’s why we needed an interior storm to keep the beauty of these patterned windows on the second floor.”

After the install, we asked Eifler what he thought about the inserts.

“They are working well and I like the look – the brown color is a bit darker than our trim color, so they’re pretty invisible, and one can still see the exterior window sash, which is great. Our house is much less drafty and the geothermal furnace does not kick on as often, so it’s quieter.  Glencoe is pretty quiet to begin with, but the commuter train isn’t too far away, and we barely hear it now.”

Bringing the Ross House back to life

Frank Lloyd Wright Ross House with restored windowsA classic Prairie-Style House, the Ross House had stood vacant for three years in what is known as the Ravine Bluffs Development. It had no heat, no running water. The exterior was covered in a plastic stucco that didn’t let the house breathe. At first, no bank would lend him money for a mortgage. But having worked on these houses for years, he understood what the Ross House could become and so he persisted.

He and his girlfriend Bonnie stripped the paint and acrylic plastic stucco and put on a new roof. They put in geothermal heating and cooling, all new plumbing, bathroom and fixtures.

The attention to windows is central to the draw of Frank Lloyd Wright homes, which are rooted in the Prairie School Architecture style with horizontal lines that evoke flat vastness of Midwestern prairies, the homes and buildings worked into the surrounding landscape whether it’s a bluff, hillside or waterfall. They always making use of natural light.  

“These are exciting properties,” Eifler said. “He looked at things much differently than other people. My house is only 1,800 square feet, but it’s a very open floor plan and comfortable. He was sensitive to windows and having natural light and views. All good things.”

The couple removed all 26 windows. They laid them on a workbench, took out the glass and used a heat gun to remove all the purple paint. Then they sanded and stained each one and put them back together. None of them have the art glass Frank Lloyd Wright was known for, but the second-floor windows have lovely ornamental mullions.

Hearing the Rain

The windows are central to the house: during warm summer rain storms, Eifler enjoys opening the second-floor ones, protected as they are from the deep eaves. The Indow inserts are easy to remove.

“They were original windows and we wanted to keep them that way,” he said. “The Indow inserts worked out well.”

Since Frank Lloyd Wright designed the entire tiny subdivision, Eifler has a house by the famed architect on either side of him as well as across the street.

Frank Lloyd Wright windows with Indow window inserts“I think I’m the only one in the whole world.”

 Join us for the next Window Hero Webinar with John Eifler on Tuesday, August 29 at 11 a.m. PT

(1 p.m. CT) You can register here.