Imagine driving through the peaceful, heavily wooded countryside of Minnetrista, Minnesota, expecting to see standard lakeside cabins or traditional suburban builds, only to find yourself staring at a structure that resembles a giant dollop of melting marshmallow or a mystical forest fungi.
The legendary Minnetrista mushroom house is a property that permanently rewrote the rules of residential architecture. Formally known as the Ensculptic house, this 1969 dwelling stands as one of the most daring, mind-boggling creative experiments of the late 20th century.
Defying every convention of traditional home design, the structure was built entirely without right angles. Let’s peel back the foam layers and step inside this historic environmental sculpture.
Table of Contents
- The Geography: An 8.4-Acre Wooded Haven on North Branch Road
- The Architect: Winslow Wedin and His Team of Dreamers
- The Construction: A Symphony of Polyurethane Foam and Burlap
- An Otherworldly Tour: No Right Angles and Sunken Conversation Pits
- Aesthetic Interpretations: Nature Meets 1960s Sci-Fi Utopia
- The Legacy of Ensculptic: Environmental Sculpture in Plastic
- The Mushroom House Today: Saving a 1969 Landmark from Demolition
1. The Geography: An 8.4-Acre Wooded Haven on North Branch Road
Located at 670 North Branch Road in Minnetrista, Minnesota, the estate occupies an exceptionally private 8.4-acre parcel. This premier geographical footprint places the home just a stone’s throw from the western shores of Lake Minnetonka.
To see how this property stands against the state’s broader architectural timeline, read our guide on the early settlements and state incorporation of Minnesota.
[The Layout of 670 North Branch Road]
Wooded Acreage
┌──────────────────────────────────────┐
│ Private Forest Line │
│ │ │
│ ▼ │
North Branch ◄┼───────► Ensculptic Dome ◄───────────┼────► 28-Foot
Road │ (No Right Angles) │ Glass Wall View
│ ▲ │
│ │ │
│ Funky Hobbit Door │
│ (Access to Green Space) │
└─────────────────┬────────────────────┘
▼
Heavily Wooded
Driveway
The property sits nestled among rolling hills, wetlands, and thick timber. This dense forest cover beautifully masks the wild interior from the rural county road.
This brilliant, private setting establishes the Minnetrista mushroom house as one of the premier destination sites for architecture students and fans of unique Minnesota homes.
2. The Architect: Winslow Wedin and His Team of Dreamers
To understand the genius of the Ensculptic house, one must look back at the radical vision of its creator. Experimental architect Winslow Wedin believed that standard rectangular homes were artificial boxes that stifled human spirit.
In the summer of 1969, Wedin took a road trip from Auburn University to Minnesota, bringing seven eager architecture students to camp out on the Minnetrista property for the summer.
Wedin’s goal was to construct a home that functioned as an organic, living “environmental sculpture in plastic” (from which the portmanteau Ensculptic was derived).
To explore how these experimental designs shook up the local landscape, check out our analysis on the development of Minnesota real estate history.
3. The Construction: A Symphony of Polyurethane Foam and Burlap
The physical execution of the Minnetrista mushroom house required an audacious departure from standard building materials. To explore how this home compared to other traditional framing materials of the era, check out our guide to early building materials and architectural styles in Minnesota.
The building crew began by stringing three-quarter-inch nylon cables into a complex spiderweb pattern across a steel and wood structural frame.
Next, they custom-fitted panels of rough burlap into the wire-mesh openings, creating a flexible fabric skeleton.
Finally, they sprayed thick layers of commercial polyurethane foam directly onto the burlap. The foam expanded and cured into a rock-hard, waterproof, and highly insulated shell within 30 seconds.
4. An Otherworldly Tour: No Right Angles and Sunken Conversation Pits
Stepping through the front entryway of the Minnetrista mushroom house is akin to stepping inside a warm, white cloud or a retro-futuristic cave. The home features approximately 4,000 square feet of flowing, organic living space split across multiple levels.
┌────────────────────────────────────────────────────────┐
│ The Famous Futuristic Features of Ensculptic │
├────────────────────────────────────────────────────────┤
│ • A cozy, sunken conversation pit built near a fireplace│
│ • Curved, gallery-white walls with no straight lines │
│ • Custom skylights carved into almost every single room │
│ • A funky, miniature "hobbit door" leading to green space│
│ • Concrete spiral staircase connecting the main levels │
│ • Built-in foam furniture sculpted directly into walls │
└────────────────────────────────────────────────────────┘
The master bathroom features an elegant crystal chandelier, while the kitchen stands as the only room displaying bold purple and orange colors.
To explore some of the original 1960s gadgets built into the walls, check out the comprehensive FOX 9 Minnesota Feature on the Minnetrista Mushroom House.
5. Aesthetic Interpretations: Nature Meets 1960s Sci-Fi Utopia
From an artistic perspective, the Minnetrista dome is a fascinating study of natural mimicry. The exterior is highly reminiscent of a biological mushroom cap, while others compare it to a melting marshmallow or a spaceship.
[The Organic Aesthetic Architecture Framework]
┌────────────────────────────────────────────────┐
│ Traditional Linear Architecture │
│ • Rigid right angles, boxy rooms, and grids │
│ • Separates the dweller from organic nature │
└───────────────────┬────────────────────────────┘
│
▼ Contrasted With
│
┌────────────────────────────────────────────────┐
│ Ensculptic Structural Design │
│ • Hand-sculpted, flowing curves & white caverns│
│ • Blends seamlessly with the wooded landscape │
└────────────────────────────────────────────────┘
Every room in the house utilizes natural daylight drawn from custom skylights, making the white foam interior feel exceptionally light and airy.
To see how these mid-century artistic designs compare to other residential trends, explore our step-by-step guide to buying a home in Minnesota.
6. The Legacy of Ensculptic: Environmental Sculpture in Plastic
While Winslow Wedin Minnetrista project remains the most famous example of the “foam house” movement, the Ensculptic concept made national waves. In March 1970, Life magazine featured the home in a multi-page photo essay, describing the interior as “wonderfully unpredictable.”
Despite the initial excitement, the polyurethane foam house concept never achieved widespread commercial success. Over the years, the home passed through several owners, eventually falling into foreclosure and abandonment.
The difficulty of securing a traditional mortgage for an unconventional foam structure made it a high-risk real estate asset.
To explore the early photos, engineering diagrams, and the architect’s own written history of the build, visit the comprehensive House and History Ensculptic Archival Registry.
7. The Mushroom House Today: Saving a 1969 Landmark from Demolition
The marketing of 670 North Branch Road represents a landmark study in preserving architectural history. In August 2010, the abandoned home was listed on the market for $237,000—a price representing the value of the land alone.
Real estate agents feared the home would be bulldosed by developers. However, in 2011, Ronald and Janis Hietala purchased the home sight-unseen for $170,000, determined to preserve Wedin’s masterpiece.
$$P_{\text{sqft}} = \frac{\text{Sale Price}}{\text{Square Footage}} = \frac{\$170,000}{4,080 \text{ sq. ft.}} \approx \$41.66 \text{ per sq. ft.}$$
With an initial purchase price of just $170,000, the buyers secured a remarkably competitive price per square foot.
To explore current luxury listings and market updates across the Lake Minnetonka region, check out our Minnesota real estate market trends 2026 guide.
┌────────────────────────────────────────────────────────┐
│ The Economic Profile of the 2011 Rescue Sale │
├────────────────────────────────────────────────────────┤
│ • Initial MLS List Price (August 2010): $237,000 │
│ • Finalized Cash Sale Price (July 2011): $170,000 │
│ • Initial Rehabilitation Investment: $50,000 │
│ • Acreage Preserved (Woodland Conservation): 8.4 Acres │
└────────────────────────────────────────────────────────┘
The new owners invested over $50,000 to overhaul the geothermal heat pump, update the wiring, repair the plumbing, and apply a fresh protective layer over the leaky roof.
To view additional photos and read historical accounts of public tours held at the estate in the 1970s, review the HomesMSP Minnesota Modern Sites Profile on Ensculptic.
By blending creative risk with historical conservation, the owners saved one of the most unforgettable landmarks on the Minnesota real estate landscape.
Frequently Asked Questions (FAQ)
What is the Minnetrista mushroom house made of?
The home was built using three-quarter-inch nylon cables strung in a spiderweb pattern, layered with custom-cut burlap panels, and sprayed with multiple layers of commercial polyurethane foam which dried into a rock-hard, insulating shell.
Can you tour the Ensculptic house today?
No, the home is a private residence and is not open for scheduled public tours. However, local visitors frequently stop by the driveway to photograph the exterior and sign a special guest book maintained by the current resident.
Who designed the foam house in Minnetrista?
The home was designed and constructed in the summer of 1969 by experimental architect Winslow Wedin, who completed the build alongside seven architecture students from Auburn University.