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The Bunker House of Tofte Minnesota

October 12, 2021 - January 15, 2022

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Located in Tofte, Minnesota, the Bunker House is a single-family High-Performance home. This 3,120 sq. ft space was completed in August of 2020 and built by Taiga Design Build. The Bunker House was constructed with structural insulated panels (SIPs) [manufactured by Energy Panel Structures] to reap the benefits of a quicker build, ease of installation, air tightness, lower utility costs, and needing less sealing than conventional framing. As the home sits on Lake Superior’s North Shore, energy efficiency was an important factor.

SIP wall thickness and core material: 6″ Neopor R30
SIP roof thickness and core material: 10″ Neopor R-50

Additionally, to being constructed with SIPs, the house is supported by large exterior glu-lam beams, has large Southern windows for natural heating in the winter, and large trees which allow extra cooling in the summer. It’s HVAC system is consisted of Dual fuel, in-floor, radiant heat. The primary heat source for the hydronic fluid is an interruptible Slant Fin Monitron electric boiler (100% efficient). The secondary source is a Navien propane boiler (95% efficient) which also serves as a secondary source of domestic hot water. EcoTech air exchanger provides outside air.

HERS Index: Estimated 28

Blower door test results: 0.89 ACH50

This SIPs high-performance home is set to weather the harsh north winds well. Surrounded with breathtaking views, it features below ground wine storage and a large walk out deck from the kitchen.

Meet the Next Generation of Insulation

BASF Neopor Plus GPS a graphite polystyrene (GPS) rigid foam insulation that gives maximum efficiency, cost-effectiveness and sustainability on construction projects. Grey Neopor Plus GPS is comprised of many small pockets of air within a polymer matrix containing graphite. The graphite reflects radiant heat energy like a mirror, increasing the material’s resistance to the flow of heat, or R-value.


October 12
January 15, 2022
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Sustainable Features
Net zero
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The Bunker House of Tofte Minnesota
Tofte, MN 55615 United States + Google Map