How They Pulled It Off: A Greenhouse on Top of a Former Garage

Welcome to How They Pulled It Off, where we take a close look at one particularly challenging aspect of a home design and get the nitty-gritty details about how it became a reality.

When Karrie Nesbit and her husband Gordon were looking for a plot of land to build on, they wanted no more than an acre. The couple had been living on pristine Lake Lemon in southern Indiana but had little room to spread out. "The houses there were on top of each other, and the area had significant building restrictions," says Nesbit. "We were looking for a little land where we could put in a garden and have a garage for storage."

They stumbled across a property of 97 acres, partially classified as forest and wildlands. On a lark, they went to see it, spending five minutes in the original old house, built in 1986 and falling apart, and about two hours exploring the grounds. Their builder, Loren Wood, told them that repairing the derelict building wouldn’t be worth the cost—it’d be better just to tear the old house down. Midway through the demo in 2021, the couple had a lightbulb moment: Why not keep the bottom portion and erect a greenhouse on top?

Project designers Russ Herndon and Allyn Lambert created the 20-by-24-foot glass greenhouse topper using a black steel frame and tempered, low-emissivity glass. The space below the greenhouse, lovingly dubbed "the bunker" by the Nesbits, has a kitchen and living quarters that serve as a small guesthouse. This space had once been the basement of the original dwelling and had been surrounded by hillside to make an earth berm-style structure. As it had originally been built into the ground, the space remains cool even when the greenhouse is 120 degrees. Automated fans kick in when the greenhouse is above 90 degrees, and the heaters turn on when it’s below 50 degrees.

The new exterior is covered in gray steel paneling to match a new build Loren Wood also constructed for the couple, a 1,400-square-foot house serving as the couple’s primary residence. This building comes with a "watchtower" and, Herndon says, is meant to mimic the form and height of the greenhouse, creating a sense of cohesion between the two buildings. Both have a modern, industrialized style boasting clean, simple lines so the ample, 360-degree views would take pride of place.

This second building is perched out on the knoll overlooking a picturesque landscape. Even though the views are outstanding, had the original owner built their earth berm home here, they would have dug down into limestone. Both the new build and the renovated building are located on the south side of Bloomington, Indiana, a college town surrounded by rolling hills and countryside. The greenhouse and watchtower capitalize on the views.

How they pulled it off: The greenhouse 

• The greenhouse has a truss system, which supports the weight of the glass, bringing the load down upon the exterior walls. 

• The greenhouse itself is made of low-emissivity glass, treated with a transparent coating that increases the energy efficiency of the glass by blocking the sun’s intense rays during summer and preventing heat escape during winter. The glass is also tempered so that it can survive a hailstorm.

• The original building’s foundation was sagging in places, and the building itself arguably should have been condemned. Once the decision was made to salvage the basement floor and place a greenhouse overtop, the team truncated the foundation, cutting it back so that it was only as big as they needed the greenhouse to be. A concrete pumper was brought in, and the team put rebar down in the core of the blocks that were then filled with concrete. Buttresses were added to shore it all up.

• The fireplace was preserved with the original masonry and some veneer in place to honor the original building.

The greenhouse idea also appealed to the homeowners because it increased the amount of entertaining space they had while enabling them to overwinter plants. As homesteaders, the couple likes to grow their own food and propagate native plants, including black willow trees, the only tree-size willow in the state and native to wetlands, that they then reintroduce to the wild.

Some of their friends and family were unsure why the couple would choose to live out in the woods. According to Nesbit, "Most people at first thought we were crazy. ‘Why leave Lake Lemon for this?’ they’d ask. But it’s such a special property, and we hated the idea of it falling into the hands of a developer." The plot is 97 acres surrounded by another lot of 300 acres surrounded by yet another lot of 100 acres. "In another 100 years, what if all this is developed? What a shame that would be."

Project Credits:

Designer: Russ Herndon and Allyn Lambert

Builder: Loren Wood Builders

Structural Engineers: Greenhouse Megastore

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